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Pham TN, Coupey J, Thariat J, Valable S. Lymphocyte radiosensitivity: An extension to the linear-quadratic model? Radiother Oncol 2024:110406. [PMID: 38925262 DOI: 10.1016/j.radonc.2024.110406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 06/13/2024] [Accepted: 06/17/2024] [Indexed: 06/28/2024]
Abstract
BACKGROUND AND PURPOSE The linear-quadratic (LQ) model has been pivotal for evaluating the effects of radiation on cells, but it is primarily characterized by linear responses, which has exhibited limitations when applied to lymphocyte data. The present research aims to address these limitations and to explore an alternative model extended from the conventional LQ model. MATERIALS AND METHODS Literature providing lymphocyte counts from assays investigating apoptosis and survival after in vitro irradiation was selected. To address the nonlinearity in lymphocyte responses to radiation, we developed a saturation model characterized by a negative exponential relationship between radiation dose and cellular response. We compared the performance of this saturation model against that of conventional models, including the LQ model and its variants (linear model LM and linear-quadratic-cubic model LQC), as well as the repair-misrepair (RMR) model. The models were evaluated based on prediction-residual plots, residual standard errors, and the Akaike information criterion (AIC). We applied the saturation model to two additional datasets: (1) a dataset from the existing literature that assessed stimulated and unstimulated human lymphocytes exposed to gamma irradiation in vitro and (2) a novel dataset involving T lymphocytes from rodent spleens after exposure to various radiation types (X-rays and protons). RESULTS The literature (n = 15 out of 2342) showed that lymphocyte apoptosis varies with dose, time and experimental conditions. The saturation model had a lower AIC of 718 compared to the LM, LQ, LQC and RMR models (AIC of 728, 720, 720 and 734, respectively). The saturation model had a lower residual error and more consistent error distribution. Integrating time as a covariate, the saturation model also had a better AIC for demonstrating time-dependent variations in lymphocyte responses after irradiation. For datasets involving unstimulated lymphocytes before irradiation, the saturation model provided a more accurate fit than did the LM, LQ, and RMR models. In these cases, the fit of the saturation model was comparable to that of the LQC model but offered an advantage when extrapolating to higher doses, where the LQC model might underestimate survival. For stimulated lymphocytes, which are radioresistant, all the models approximated the LM. Both the LQ and saturation models indicated greater radiosensitivity to protons in vitro. CONCLUSION The new "saturation model" performed better than the LQ model in quantifying lymphocyte apoptosis and survival, estimating time dependency and assessing the role of radiation modalities or lymphocyte stimulation. Further experiments are warranted to experimentally explore the validity of the saturation model as a promising alternative in the clinical setting.
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Affiliation(s)
- Thao-Nguyen Pham
- Université de Caen Normandie, CNRS, Normandie Université, ISTCT UMR6030, GIP CYCERON, F-14000 Caen, France; Laboratoire de Physique Corpusculaire, UMR6534 IN2P3/ENSICAEN, France - Normandie Université, France
| | - Julie Coupey
- Université de Caen Normandie, CNRS, Normandie Université, ISTCT UMR6030, GIP CYCERON, F-14000 Caen, France
| | - Juliette Thariat
- Laboratoire de Physique Corpusculaire, UMR6534 IN2P3/ENSICAEN, France - Normandie Université, France; Department of Radiation Oncology, Centre François Baclesse, Caen, Normandy, France.
| | - Samuel Valable
- Université de Caen Normandie, CNRS, Normandie Université, ISTCT UMR6030, GIP CYCERON, F-14000 Caen, France.
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Song YC, Chen SY, Zhao XR, Jing H, Fang H, Tang Y, Hu SY, Song YW, Jin J, Liu YP, Qi SN, Sun GY, Zhong QZ, Du XH, Liu J, Li YX, Wang SL. Prognostic value of lymphocytes in patients with breast cancer receiving radiotherapy after breast-conserving surgery: A post hoc analysis of a phase III randomized trial. Radiother Oncol 2024:110390. [PMID: 38897316 DOI: 10.1016/j.radonc.2024.110390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 06/11/2024] [Accepted: 06/16/2024] [Indexed: 06/21/2024]
Abstract
PURPOSE To evaluate the prognostic value of peripheral lymphocyte count (PLC) in the breast cancer patients after breast-conserving surgery (BCS) with radiotherapy (RT). METHODS AND MATERIALS This post hoc analysis was performed using data of 628 patients from a phase III, randomized controlled trial comparing hypofractionated RT (HFRT) with conventional fractionated RT (CFRT) after BCS. PLCs were obtained before, during, and after RT until the 1-year follow-up. The optimal cut-off PLCs were determined using the maxstat package in R. Survival rates were estimated using the Kaplan-Meier method and compared with the log-rank test. RESULTS A total of 275 (46.1 %) patients developed lymphopenia during RT, among them, 17 (2.8 %) had grade 3 lymphopenia and no one developed grade 4 lymphopenia. With a median follow-up of 110.8 months, patients with pre-RT PLCs of < 1.77 × 109/L had a significantly lower 10-year breast cancer-specific survival (BCSS) rate (P = 0.013) and overall survival (OS) rate (P = 0.026). Patients with a nadir PLC of < 1.35 × 109/L had a significantly poorer 10-year OS rate (P = 0.048). Multivariate analysis showed that a pre-RT PLC of < 1.77 × 109/L was an independent factor influencing BCSS and OS, while the effect of the nadir PLC did not remain significant. Neither PLC nor lymphopenia recovery at post-RT 1, 3, and 6 months and 1 year was associated with survival. CONCLUSIONS Radiation-induced lymphopenia in patients with breast cancer after BCS tends to be mild. The lower pre-RT PLC predicted poorer survival.
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Affiliation(s)
- Yu-Chun Song
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China.
| | - Si-Ye Chen
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Xu-Ran Zhao
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Hao Jing
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Hui Fang
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Yu Tang
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Shang-Ying Hu
- Department of Cancer Epidemiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China.
| | - Yong-Wen Song
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Jing Jin
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Yue-Ping Liu
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Shu-Nan Qi
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Guang-Yi Sun
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Qiu-Zi Zhong
- Department of Radiation Oncology, Beijing Hospital, Ministry of Health, Beijing, China
| | - Xiang-Hui Du
- Department of Radiation Therapy, Cancer Hospital of the University of Chinese Academy of Sciences, Zhejiang Cancer Hospital, Hangzhou, Zhejiang Province, China
| | - Juan Liu
- Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai, China.
| | - Ye-Xiong Li
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China.
| | - Shu-Lian Wang
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China.
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Weng KG, Lei HK, Shen DS, Wang Y, Zhu XD. Treatment-Related Lymphopenia is Possibly a Marker of Good Prognosis in Nasopharyngeal Carcinoma: a Propensity-Score Matching Analysis. Cancer Manag Res 2024; 16:603-616. [PMID: 38855327 PMCID: PMC11162643 DOI: 10.2147/cmar.s456717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 05/21/2024] [Indexed: 06/11/2024] Open
Abstract
Purpose The aims of the study were to monitor circulating lymphocyte subset counts before and after therapy for nasopharyngeal carcinoma (NPC), and investigate their relationships with patient outcomes. Patients and Methods Subjects comprised patients with TNM stage I-IVA NPC who underwent radiotherapy. Peripheral venous blood samples were collected before and after treatment. Lymphocyte subset counts were analyzed by flow cytometry. Differences between post-treatment and baseline counts were calculated to determine Δ values. Patients were divided into high and low groups, based on median lymphocyte subset counts; propensity score matching was applied to balance groups. Progression-free survival (PFS) and overall survival (OS) were plotted using Kaplan-Meier curves and compared using a Log rank test. Relationships between lymphocyte subset counts and patient survival were subjected to Cox regression analysis. Results Patients with NPC (n=746) were enrolled from 2012-2022. Higher CD8+ and total T cell baseline counts were associated with better 5-year PFS (73.7% vs 63.1%, P=0.002 and 73.8% vs 64.1%, P=0.005, respectively). Similarly, higher Δ values of CD4+ and total T cells were associated with higher 5-year PFS (76.2% vs 63.5%, P=0.001; 74.3% vs 65.4%, P=0.010) and OS (89.8% vs 81.6%, P=0.005; 88.6% vs 82.5%, P=0.009). Multivariate Cox regression revealed that CD8+ (hazard ratio (HR) 0.651, P=0.002) and total T (HR 0.600, P<0.001) cells were significantly associated with PFS. CD4+ (HR 0.708, P=0.038) and total T (HR 0.639, P=0.031) cells were independent prognostic factors for OS. Conclusion NPC patients with low total or CD8+ T cell counts before treatment had worse prognosis; however, those with more significant decreases in total or CD4+ T cells possibly had better outcomes. T cell counts can be reliable indicators to predict prognosis.
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Affiliation(s)
- Ke-gui Weng
- Department of Radiation Oncology, Guangxi Medical University Cancer Hospital, Nanning, Guangxi, People’s Republic of China
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, People’s Republic of China
| | - Hai-ke Lei
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, People’s Republic of China
| | - De-Song Shen
- Department of Oncology, Liuzhou People’s Hospital Affiliated to Guangxi Medical University, Liuzhou, Guangxi, People’s Republic of China
| | - Ying Wang
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, People’s Republic of China
| | - Xiao-Dong Zhu
- Department of Radiation Oncology, Guangxi Medical University Cancer Hospital, Nanning, Guangxi, People’s Republic of China
- Department of Oncology, Wuming Hospital of Guangxi Medical University, Nanning, Guangxi, People’s Republic of China
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Colen J, Nguyen C, Liyanage SW, Aliotta E, Chen J, Alonso C, Romano K, Peach S, Showalter T, Read P, Larner J, Wijesooriya K. Predicting radiation-induced immune suppression in lung cancer patients treated with stereotactic body radiation therapy. Med Phys 2024. [PMID: 38837261 DOI: 10.1002/mp.17181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 03/14/2024] [Accepted: 04/21/2024] [Indexed: 06/07/2024] Open
Abstract
BACKGROUND Stereotactic body radiation therapy (SBRT) is known to modulate the immune system and contribute to the generation of anti-tumor T cells and stimulate T cell infiltration into tumors. Radiation-induced immune suppression (RIIS) is a side effect of radiation therapy that can decrease immunological function by killing naive T cells as well as SBRT-induced newly created effector T cells, suppressing the immune response to tumors and increasing susceptibility to infections. PURPOSE RIIS varies substantially among patients and it is currently unclear what drives this variability. Models that can accurately predict RIIS in near real time based on treatment plan characteristics would allow treatment planners to maintain current protocol specific dosimetric criteria while minimizing immune suppression. In this paper, we present an algorithm to predict RIIS based on a model of circulating blood using early stage lung cancer patients treated with SBRT. METHODS This Python-based algorithm uses DICOM data for radiation therapy treatment plans, dose maps, patient CT data sets, and organ delineations to stochastically simulate blood flow and predict the doses absorbed by circulating lymphocytes. These absorbed doses are used to predict the fraction of lymphocytes killed by a given treatment plan. Finally, the time dependence of absolute lymphocyte count (ALC) following SBRT is modeled using longitudinal blood data up to a year after treatment. This model was developed and evaluated on a cohort of 64 patients with 10-fold cross validation. RESULTS Our algorithm predicted post-treatment ALC with an average error of0.24 ± 0.21 × 10 9 $0.24 \pm 0.21 \times {10}^9$ cells/L with 89% of the patients having a prediction error below 0.5 × 109 cells/L. The accuracy was consistent across a wide range of clinical and treatment variables. Our model is able to predict post-treatment ALC < 0.8 (grade 2 lymphopenia), with a sensitivity of 81% and a specificity of 98%. This model has a ∼38-s end-to-end prediction time of post treatment ALC. CONCLUSION Our model performed well in predicting RIIS in patients treated using lung SBRT. With near-real time model prediction time, it has the capability to be interfaced with treatment planning systems to prospectively reduce immune cell toxicity while maintaining national SBRT conformity and plan quality criteria.
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Affiliation(s)
- Jonathan Colen
- University of Virginia, Department of Physics, Charlottesville, Virginia, USA
- Old Dominion University, Joint Institute on Advanced Computing for Environmental Studies, Norfolk, Virginia, USA
- Hampton Roads Biomedical Research Consortium, Portsmouth, Virginia, USA
| | - Cam Nguyen
- University of Virginia, Department of Physics, Charlottesville, Virginia, USA
| | - Seth W Liyanage
- Stanford University, Department of Mechanical Engineering, Stanford, California, USA
| | - Eric Aliotta
- University of Virginia, Department of Radiation Oncology, Charlottesville, Virginia, USA
| | - Joe Chen
- University of Virginia, Department of Radiation Oncology, Charlottesville, Virginia, USA
| | - Clayton Alonso
- University of Virginia, Department of Radiation Oncology, Charlottesville, Virginia, USA
| | - Kara Romano
- University of Virginia, Department of Radiation Oncology, Charlottesville, Virginia, USA
| | - Sean Peach
- University of Virginia, Department of Radiation Oncology, Charlottesville, Virginia, USA
| | - Timothy Showalter
- University of Virginia, Department of Radiation Oncology, Charlottesville, Virginia, USA
| | - Paul Read
- University of Virginia, Department of Radiation Oncology, Charlottesville, Virginia, USA
| | - James Larner
- University of Virginia, Department of Radiation Oncology, Charlottesville, Virginia, USA
| | - Krishni Wijesooriya
- University of Virginia, Department of Physics, Charlottesville, Virginia, USA
- University of Virginia, Department of Radiation Oncology, Charlottesville, Virginia, USA
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Iori F, Torelli N, Unkelbach J, Tanadini-Lang S, Christ SM, Guckenberger M. An in-silico planning study of stereotactic body radiation therapy for polymetastatic patients with more than ten extra-cranial lesions. Phys Imaging Radiat Oncol 2024; 30:100567. [PMID: 38516028 PMCID: PMC10950805 DOI: 10.1016/j.phro.2024.100567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 03/01/2024] [Accepted: 03/01/2024] [Indexed: 03/23/2024] Open
Abstract
Background and purpose Limited data is available about the feasibility of stereotactic body radiation therapy (SBRT) for treating more than five extra-cranial metastases, and almost no data for treating more than ten. The aim of this study was to investigate the feasibility of SBRT in this polymetatstatic setting. Materials and methods Consecutive metastatic melanoma patients with more than ten extra-cranial metastases and a maximum lesion diameter below 11 cm were selected from a single-center prospective registry for this in-silico planning study. For each patient, SBRT plans were generated to treat all metastases with a prescribed dose of 5x7Gy, and dose-limiting organs (OARs) were analyzed. A cell-kill based inverse planning approach was used to automatically determine the maximum deliverable dose to each lesion individually, while respecting all OARs constraints. Results A total of 23 polymetastatic patients with a medium of 17 metastases (range, 11-51) per patient were selected. SBRT plans with sufficient target coverage and respected OARs dose constraints were achieved in 16 out of 23 patients. In the remaining seven patients, the lungs V5Gy < 80 % and the liver D700 cm3 < 15Gy were most frequently the dose-limiting constraints. The cell-kill based planning approach allowed optimizing the dose administration depending on metastases total volume and location. Conclusion This retrospective planning study shows the feasibility of definitive SBRT for 70% of polymetastatic patients with more than ten extra-cranial lesions and proposes the cell-killing planning approach as an approach to individualize treatment planning in polymetastatic patients'.
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Affiliation(s)
- Federico Iori
- Radiation Oncology Unit, Azienda USL-IRCCS di Reggio Emilia, 42122 Reggio Emilia, Italy
- Department of Radiation Oncology, University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
- Clinical and Experimental Medicine PhD Program, Department of Biomedical, Metabolic, and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Nathan Torelli
- Department of Radiation Oncology, University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
| | - Jan Unkelbach
- Department of Radiation Oncology, University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
| | - Stephanie Tanadini-Lang
- Department of Radiation Oncology, University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
| | - Sebastian M. Christ
- Department of Radiation Oncology, University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
| | - Matthias Guckenberger
- Department of Radiation Oncology, University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
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Nowicka Z, Kuna K, Łaszczych M, Łazar-Poniatowska M, Sobocki BK, Stawiski K, Dąbrowski M, Bruski K, Zięba A, Pajdziński M, Staniewska E, Miszczyk M, Paganetti H, Fendler W, Tomasik B. Dose-volume metric-based prediction of radiotherapy-induced lymphocyte loss in patients with non-small-cell lung cancer treated with modern radiotherapy techniques. Phys Imaging Radiat Oncol 2024; 30:100593. [PMID: 38912008 PMCID: PMC11190719 DOI: 10.1016/j.phro.2024.100593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 05/12/2024] [Accepted: 05/25/2024] [Indexed: 06/25/2024] Open
Abstract
Background and Purpose Radiation-induced lymphopenia (RIL) is a common side effect of radiotherapy (RT) that may negatively impact survival. We aimed to identify RIL predictors in patients with non-small-cell lung cancer (NSCLC) treated intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT). Materials and Methods We retrospectively analysed data of 306 patients who underwent radical RT for NSCLC. Absolute lymphocyte count (ALC) loss was evaluated for each patient by fitting an exponential decay curve to data from first 45 days since treatment start, and percentage ALC loss relative to baseline was calculated based on area under the decay curve and baseline ALC. We compared IMRT and VMAT treatment plans and used linear regression to predict ALC loss. Results ALC decreased during RT in the whole patient group, while neutrophil counts remained stable and decreased only in those treated with concurrent chemoradiotherapy (CRT). Percentage ALC loss ranged between 11 and 78 % and was more strongly than lymphocyte nadir correlated with dose-volume metrics for relevant normal structures. We found evidence for the association of high radiation dose to the lungs, heart and body with percentage ALC loss, with lung volume exposed to 20-30 Gy being most important predictors in patients treated with IMRT. A multivariable model based on CRT use, baseline ALC and first principal component (PC1) of the dose-volume predictors showed good predictive performance (bias-corrected R2 of 0.40). Conclusion Percentage lymphocyte loss is a robust measure of RIL that is predicted by baseline ALC, CRT use and dose-volume parameters to the lungs, heart and body.
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Affiliation(s)
- Zuzanna Nowicka
- Department of Biostatistics and Translational Medicine, Medical University of Łódź, Łódź, Poland
| | - Kasper Kuna
- Department of Biostatistics and Translational Medicine, Medical University of Łódź, Łódź, Poland
| | - Mateusz Łaszczych
- Department of Biostatistics and Translational Medicine, Medical University of Łódź, Łódź, Poland
| | | | - Bartosz Kamil Sobocki
- Department of Oncology and Radiotherapy, Medical University of Gdańsk, Faculty of Medicine, Gdańsk, Poland
| | - Konrad Stawiski
- Department of Biostatistics and Translational Medicine, Medical University of Łódź, Łódź, Poland
| | - Michał Dąbrowski
- Department of Oncology and Radiotherapy, Medical University of Gdańsk, Faculty of Medicine, Gdańsk, Poland
| | - Konrad Bruski
- Department of Oncology and Radiotherapy, Medical University of Gdańsk, Faculty of Medicine, Gdańsk, Poland
| | - Adam Zięba
- Department of Radiotherapy, Medical University of Łódź, Łódź, Poland
| | | | - Emilia Staniewska
- 3 Radiotherapy and Chemotherapy Department, Maria Skłodowska-Curie National Research Institute of Oncology, Gliwice, Poland
| | - Marcin Miszczyk
- 3 Radiotherapy and Chemotherapy Department, Maria Skłodowska-Curie National Research Institute of Oncology, Gliwice, Poland
- Collegium Medicum, Faculty of Medicine, WSB University, Dąbrowa Górnicza, Poland
| | - Harald Paganetti
- Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Wojciech Fendler
- Department of Biostatistics and Translational Medicine, Medical University of Łódź, Łódź, Poland
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Bartłomiej Tomasik
- Department of Oncology and Radiotherapy, Medical University of Gdańsk, Faculty of Medicine, Gdańsk, Poland
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Cella L, Monti S, Pacelli R, Palma G. Modeling frameworks for radiation induced lymphopenia: A critical review. Radiother Oncol 2024; 190:110041. [PMID: 38042499 DOI: 10.1016/j.radonc.2023.110041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 11/17/2023] [Accepted: 11/25/2023] [Indexed: 12/04/2023]
Abstract
Radiation-induced lymphopenia (RIL) is a frequent, and often considered unavoidable, side effect of radiation therapy (RT), whether or not chemotherapy is included. However, in the last few years several studies have demonstrated the detrimental effect of RIL on therapeutic outcomes, with conflicting findings concerning possible inferior patient survival. In addition, since immunotherapeutic treatment has become an integral part of cancer therapy, preserving the immune system is recognized as crucial. Given this background, various research groups have reported on different frameworks for modelling RIL, frequently based on different definitions of RIL itself, and discordant results have been reported. Our aim is to critically review the current literature on RIL modelling and summarize the different approaches recently proposed to improve the prediction of RIL after RT and aimed at immunity-sparing RT. A detailed description of these approaches will be outlined and illustrated through their applications as found in the literature from the last five years. Such a critical analysis represents the necessary starting step to develop an effective strategy that ultimately could harmonize the diverse modelling methods.
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Affiliation(s)
- Laura Cella
- Institute of Biostructures and Bioimaging, National Research Council, Naples, Italy.
| | - Serena Monti
- Institute of Biostructures and Bioimaging, National Research Council, Naples, Italy
| | - Roberto Pacelli
- Department of Advanced Biomedical Sciences, Federico II School of Medicine, Naples, Italy
| | - Giuseppe Palma
- Institute of Nanotechnology, National Research Council, Lecce, Italy
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Beekman C, Withrow JD, Correa Alfonso CM, Pathak SP, Dawson RJ, Carrasco-Rojas N, Sforza AR, Colon CG, Bolch WE, Grassberger C, Paganetti H. A stochastic model of blood flow to calculate blood dose during radiotherapy. Phys Med Biol 2023; 68:10.1088/1361-6560/ad02d6. [PMID: 37827171 PMCID: PMC10695181 DOI: 10.1088/1361-6560/ad02d6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 10/12/2023] [Indexed: 10/14/2023]
Abstract
Purpose. Lymphopenia is a common side effect in patients treated with radiotherapy, potentially caused by direct cell killing of circulating lymphocytes in the blood. To investigate this hypothesis, a method to assess dose to circulating lymphocytes is needed.Methods. A stochastic model to simulate systemic blood flow in the human body was developed based on a previously designed compartment model. Blood dose was obtained by superimposing the spatiotemporal distribution of blood particles with a time-varying dose rate field, and used as a surrogate for dose to circulating lymphocytes. We discuss relevant theory on compartmental modeling and how to combine it with models of explicit organ vasculature.Results. A general workflow was established which can be used for any anatomical site. Stochastic compartments can be replaced by explicit models of organ vasculatures for improved spatial resolution, and tumor compartments can be dynamically assigned. Generating a patient-specific blood flow distribution takes about one minute, fast enough to investigate the effect of varying treatment parameters such as the dose rate. Furthermore, the anatomical structures contributing most to the overall blood dose can be identified, which could potentially be used for lymphocyte-sparing treatment planning.Conclusion. The ability to report the blood dose distribution during radiotherapy is imperative to test and act upon the current paradigm that radiation-induced lymphopenia is caused by direct cell killing of lymphocytes in the blood. We have built a general model that can do so for various treatment sites. The presented framework is publicly available athttp://github.com/mghro/hedos.
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Affiliation(s)
- Chris Beekman
- Massachusetts General Hospital/Harvard Medical School, United States of America
| | | | | | | | | | | | | | | | | | - Clemens Grassberger
- Massachusetts General Hospital/Harvard Medical School, United States of America
- University of Washington, United States of America
| | - Harald Paganetti
- Massachusetts General Hospital/Harvard Medical School, United States of America
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9
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Paganetti H. A review on lymphocyte radiosensitivity and its impact on radiotherapy. Front Oncol 2023; 13:1201500. [PMID: 37601664 PMCID: PMC10435323 DOI: 10.3389/fonc.2023.1201500] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 07/17/2023] [Indexed: 08/22/2023] Open
Abstract
It is well known that radiation therapy causes lymphopenia in patients and that this is correlated with a negative outcome. The mechanism is not well understood because radiation can have both immunostimulatory and immunosuppressive effects. How tumor dose conformation, dose fractionation, and selective lymph node irradiation in radiation therapy does affect lymphopenia and immune response is an active area of research. In addition, understanding the impact of radiation on the immune system is important for the design and interpretation of clinical trials combining radiation with immune checkpoint inhibitors, both in terms of radiation dose and treatment schedules. Although only a few percent of the total lymphocyte population are circulating, it has been speculated that their increased radiosensitivity may contribute to, or even be the primary cause of, lymphopenia. This review summarizes published data on lymphocyte radiosensitivity based on human, small animal, and in vitro studies. The data indicate differences in radiosensitivity among lymphocyte subpopulations that affect their relative contribution and thus the dynamics of the immune response. In general, B cells appear to be more radiosensitive than T cells and NK cells appear to be the most resistant. However, the reported dose-response data suggest that in the context of lymphopenia in patients, aspects other than cell death must also be considered. Not only absolute lymphocyte counts, but also lymphocyte diversity and activity are likely to be affected by radiation. Taken together, the reviewed data suggest that it is unlikely that radiation-induced cell death in lymphocytes is the sole factor in radiation-induced lymphopenia.
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Affiliation(s)
- Harald Paganetti
- Department of Radiation Oncology, Massachusetts General Hospital, Boston MA, United States
- Harvard Medical School, Boston MA, United States
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10
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Cai S, Fan Y, Guo Q, Sun Y, Zhao P, Tian Y, Fan Q. Impact of Radiation Dose to Circulating Immune Cells on Tumor Control and Survival in Esophageal Cancer. Cancer Biother Radiopharm 2023; 38:380-387. [PMID: 34883023 DOI: 10.1089/cbr.2021.0250] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Background: The immune system is well known to exert tumor immunosurveillance effects, and that immune cells circulating in the peripheral blood affect tumor prognosis. The study investigated the effect of estimated dose of radiation on circulating immune cells (EDRIC) and tumor control for esophageal cancer patients treated with concurrent chemo-radiotherapy. Materials and Methods: A total of 146 esophageal cancer patients treated with radiotherapy between January 2016 and June 2020 were retrospectively identified. We determined EDRIC, known prognostic factors, and the association of these factors with progression-free survival (PFS) and overall survival (OS). Results: The median follow-up was 17.9 months (2.7-60.4 months). The 3-year OS was 39.2%. Severe post-treatment lymphopenia was observed in 84.2% of patients. A negative correlation between EDRIC and absolute lymphocyte count was found (r = -0.679; p < 0.001). Patients with EDRIC ≥10.3 Gy were more likely to demonstrate grade 4 lymphopenia (55.2% vs. 4.5%; p < 0.001). Patients with grade 4 lymphopenia had a worse OS and PFS. On multivariate analysis, EDRIC was independently associated with OS (hazard ratio [HR], 1.142; p = 0.016) and PFS (HR, 1.121; p = 0.019). Conclusions: EDRIC can predict lymphocyte reduction and poor prognosis for esophageal cancer patients treated with radiotherapy.
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Affiliation(s)
- Shang Cai
- Department of Radiotherapy & Oncology, The Second Affiliated Hospital of Soochow University, Institute of Radiation Oncology, Soochow University, Suzhou, China
| | - Yawen Fan
- Department of Radiotherapy & Oncology, The Second Affiliated Hospital of Soochow University, Institute of Radiation Oncology, Soochow University, Suzhou, China
| | - Qi Guo
- Department of Radiotherapy & Oncology, The Second Affiliated Hospital of Soochow University, Institute of Radiation Oncology, Soochow University, Suzhou, China
| | - Yanze Sun
- Department of Radiotherapy & Oncology, The Second Affiliated Hospital of Soochow University, Institute of Radiation Oncology, Soochow University, Suzhou, China
| | - Peifeng Zhao
- Department of Radiotherapy & Oncology, The Second Affiliated Hospital of Soochow University, Institute of Radiation Oncology, Soochow University, Suzhou, China
| | - Ye Tian
- Department of Radiotherapy & Oncology, The Second Affiliated Hospital of Soochow University, Institute of Radiation Oncology, Soochow University, Suzhou, China
| | - Qiuhong Fan
- Department of Radiotherapy & Oncology, The Second Affiliated Hospital of Soochow University, Institute of Radiation Oncology, Soochow University, Suzhou, China
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Zheng W, Chen Q, Liu H, Zeng L, Zhou Y, Liu X, Bai Y, Zhang J, Pan Y, Shao C. SDC1-dependent TGM2 determines radiosensitivity in glioblastoma by coordinating EPG5-mediated fusion of autophagosomes with lysosomes. Autophagy 2023; 19:839-857. [PMID: 35913916 PMCID: PMC9980589 DOI: 10.1080/15548627.2022.2105562] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Glioblastoma multiforme (GBM) is the most common brain malignancy insensitive to radiotherapy (RT). Although macroautophagy/autophagy was reported to be a fundamental factor prolonging the survival of tumors under radiotherapeutic stress, the autophagic biomarkers coordinated to radioresistance of GBM are still lacking in clinical practice. Here we established radioresistant GBM cells and identified their protein profiles using tandem mass tag (TMT) quantitative proteomic analysis. It was found that SDC1 and TGM2 proteins were overexpressed in radioresistant GBM cells and tissues and they contributed to the poor prognosis of RT. Knocking down SDC1 and TGM2 inhibited the fusion of autophagosomes with lysosomes and thus enhanced the radiosensitivity of GBM cells. After irradiation, TGM2 bound with SDC1 and transported it from the cell membrane to lysosomes, and then bound to LC3 through its two LC3-interacting regions (LIRs), coordinating the encounter between autophagosomes and lysosomes, which should be a prerequisite for lysosomal EPG5 to recognize LC3 and subsequently stabilize the STX17-SNAP29-VAMP8 QabcR SNARE complex assembly. Moreover, when combined with RT, cystamine dihydrochloride (a TGM2 inhibitor) extended the lifespan of GBM-bearing mice. Overall, our findings demonstrated the EPG5 tethering mode with SDC1 and TGM2 during the fusion of autophagosomes with lysosomes, providing new insights into the molecular mechanism and therapeutic target underlying radioresistant GBM.Abbreviations: BafA1: bafilomycin A1; CQ: chloroquine; Cys-D: cystamine dihydrochloride; EPG5: ectopic P-granules 5 autophagy tethering factor; GBM: glioblastoma multiforme; GFP: green fluorescent protein; LAMP2: lysosomal associated membrane protein 2; LIRs: LC3-interacting regions; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; NC: negative control; RFP: red fluorescent protein; RT: radiotherapy; SDC1: syndecan 1; SNAP29: synaptosome associated protein 29; SQSTM1/p62: sequestosome 1; STX17: syntaxin 17; TGM2: transglutaminase 2; TMT: tandem mass tag; VAMP8: vesicle associated membrane protein 8; WT: wild type.
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Affiliation(s)
- Wang Zheng
- Institute of Radiation Medicine, Shanghai Medical College, Fudan University, Shanghai, China
| | - Qianping Chen
- Institute of Radiation Medicine, Shanghai Medical College, Fudan University, Shanghai, China
| | - Hongxia Liu
- Institute of Radiation Medicine, Shanghai Medical College, Fudan University, Shanghai, China
| | - Liang Zeng
- Institute of Radiation Medicine, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yuchuan Zhou
- Institute of Radiation Medicine, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xinglong Liu
- Institute of Radiation Medicine, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yang Bai
- Institute of Radiation Medicine, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jianghong Zhang
- Institute of Radiation Medicine, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yan Pan
- Institute of Radiation Medicine, Shanghai Medical College, Fudan University, Shanghai, China
| | - Chunlin Shao
- Institute of Radiation Medicine, Shanghai Medical College, Fudan University, Shanghai, China
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Sung W, Cho B. Modeling of radiation effects to immune system: a review. THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY 2022; 81:1013-1019. [PMID: 35966936 PMCID: PMC9358382 DOI: 10.1007/s40042-022-00574-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 03/17/2022] [Accepted: 05/18/2022] [Indexed: 06/15/2023]
Abstract
Cancer metastasis is the major cause of cancer mortality and accounts for about 90% of cancer death. Although radiation therapy has been considered to reduce the localized cancer burden, emerging evidence that radiation can potentially turn tumors into an in situ vaccine has raised significant interest in combining radiation with immunotherapy. However, the combination approach might be limited by the radiation-induced immunosuppression. Assessment of radiation effects on the immune system at the patient level is critical to maximize the systemic antitumor response of radiation. In this review, we summarize the developed solutions in three different categories for systemic radiation therapy: blood dose, radiation-induced lymphopenia, and tumor control. Furthermore, we address how they could be combined to optimize radiotherapy regimens and maximize their synergy with immunotherapy.
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Affiliation(s)
- Wonmo Sung
- Department of Biomedical Engineering and of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Byungchul Cho
- Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
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13
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Yu H, Chen F, Lam KO, Yang L, Wang Y, Jin JY, EI Helali A, Kong FM(S. Potential Determinants for Radiation-Induced Lymphopenia in Patients With Breast Cancer Using Interpretable Machine Learning Approach. Front Immunol 2022; 13:768811. [PMID: 35799797 PMCID: PMC9253393 DOI: 10.3389/fimmu.2022.768811] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 05/23/2022] [Indexed: 11/13/2022] Open
Abstract
Radiation-induced lymphopenia is known for its survival significance in patients with breast cancer treated with radiation therapy. This study aimed to evaluate the impact of radiotherapy on lymphocytes by applying machine learning strategies. We used Extreme Gradient Boosting (XGboost) to predict the event of lymphopenia (grade≥1) and conduced an independent validation. Then, we induced feature attribution analysis (Shapley additive explanation, SHAP) in explaining the XGboost models to explore the directional contribution of each feature to lymphopenia. Finally, we implemented the proof-of-concept clinical validation. The results showed that the XGboost models had rigorous generalization performances (accuracies 0.764 and ROC-AUC 0.841, respectively) in the independent cohort. The baseline lymphocyte counts are the most protective feature (SHAP = 5.226, direction of SHAP = -0.964). Baseline platelets and monocytes also played important protective roles. The usage of taxane only chemotherapy was less risk on lymphopenia than the combination of anthracycline and taxane. By the contribution analysis of dose, we identified that firstly lymphocytes were sensitive to a radiation dose less than 4Gy; secondly the irradiation volume was more important in promoting lymphopenia than the irradiation dose; thirdly the irradiation dose promoted the event of lymphopenia when the irradiation volume was fixed. Overall, our findings paved the way to clarifying the radiation dose volume effect. To avoid radiation-induced lymphopenia, irradiation volume should be kept to a minimum during the planning process, as long as the target coverage is not compromised.
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Affiliation(s)
- Hao Yu
- Institute of Biomedical and Health Engineering, Chinese Academy of Sciences Shenzhen Institutes of Advanced Technology, Shenzhen, China
| | - Fang Chen
- Department of Clinical Oncology, University of Hong Kong-Shenzhen Hospital, Shenzhen, China
- Department of Clinical Oncology, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Ka-On Lam
- Department of Clinical Oncology, University of Hong Kong-Shenzhen Hospital, Shenzhen, China
- Department of Clinical Oncology, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Li Yang
- Department of Clinical Oncology, University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Yang Wang
- Biomedical Engineering, Shenzhen Polytechnic, Shenzhen, China
| | - Jian-Yue Jin
- University Hospitals/Cleverland Medical Center, Seidman Cancer Center and Case Western Reserve University, Cleveland, OH, United States
| | - Aya EI Helali
- Department of Clinical Oncology, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Feng-Ming (Spring) Kong
- Department of Clinical Oncology, University of Hong Kong-Shenzhen Hospital, Shenzhen, China
- Department of Clinical Oncology, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
- *Correspondence: Feng-Ming (Spring) Kong,
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14
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Chen F, Jin JY, Hui TSK, Jing H, Zhang H, Nong Y, Han Y, Wang W, Ma L, Yi F, Chen Q, Zhang Y, Fu P, Yang L, Xu Z, Kong FMS. Radiation Induced Lymphopenia Is Associated With the Effective Dose to the Circulating Immune Cells in Breast Cancer. Front Oncol 2022; 12:768956. [PMID: 35600350 PMCID: PMC9118537 DOI: 10.3389/fonc.2022.768956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Accepted: 03/28/2022] [Indexed: 11/21/2022] Open
Abstract
Background Lymphopenia is a known significant factor for treatment outcome in cancer patients, with underlying risk factor poorly understood in breast cancer. We hypothesize that the effective dose to the circulating immune cells (EDIC) which was related with lymphopenia in lung cancer will also have significant effect for radiation induced lymphopenia (RIL) in patients with breast cancer. Material and Methods Patients treated with adjuvant radiotherapy (RT) and with complete blood tests within one week from RT end/start (post/preRT) were eligible in this study. Radiation dosimetric factors were collected retrospectively, and EDIC for each patient was calculated based on the doses to lung, heart and total body according to the model description, as previously reported. RIL was defined by the CTCAE5.0 based on postRT peripheral lymphocyte count (PLC). Linear regression was first used to test the correlation between EDIC with post/preRT PLC ratio and postRT PLC, using all these as continuous variables. Normal tissue complication probability (NTCP) was used to develop models that predict the CTCAE graded RIL from EDIC. Results A total of 735 patients were eligible. The mean post/preRT PLC ratio was 0.66 (95% CI: 0.64-0.68) and mean EDIC of breast cancer was 1.70Gy (95% CI: 1.64-1.75). Both post/preRT PLC ratio and postRT PLC were significantly correlated with EDIC (P<0.001), with R2 of 0.246. For patients with normal preRT PLC, the post/preRT PLC ratio was better associated with EDIC, and postRT PLC was expressed as PLCpreRT × (0.89 – 0.16 × EDIC). For patients with preRT lymphopenia, postRT PLC was better associated with EDIC and it was 1.1 – 0.17 × EDIC. Using binned EDIC as the dose variable, the bootstrap validated NTCPs fit the data nicely with R2 of 0.93, 0.96, and 0.94 for grade-1, grade-2, and grade-3 RIL, respectively. The corresponding EDIC to induce 50% of grade-1, grade-2 and grade-3 RIL was 1.2, 2.1 and 3.7 Gy, respectively. Conclusion EDIC is a significant factor for RIL in patients with breast cancer, and may be used to compute the risk of lymphopenia in each individual patient with the use of the conventional NTCP modeling. External validation is needed before the EDIC can be used to guide RT plan.
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Affiliation(s)
- Fang Chen
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China.,Department of Clinical Oncology, Hong Kong University Li Ka Shing Medical School, Hong Kong, Hong Kong SAR, China
| | - Jian-Yue Jin
- Department of Radiation Oncology, Case Western Reserve University, Cleveland, OH, United States
| | - Timothy S K Hui
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Haiman Jing
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Hong Zhang
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Yaqing Nong
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Ying Han
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Weili Wang
- Department of Radiation Oncology, Case Western Reserve University, Cleveland, OH, United States
| | - Lingyu Ma
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Fan Yi
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Qingqing Chen
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Yongsheng Zhang
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Pingfu Fu
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, Cleveland, OH, United States
| | - Li Yang
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Zhiyuan Xu
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Feng-Ming Spring Kong
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China.,Department of Clinical Oncology, Hong Kong University Li Ka Shing Medical School, Hong Kong, Hong Kong SAR, China
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15
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Jin JY. Prospect of radiotherapy technology development in the era of immunotherapy. JOURNAL OF THE NATIONAL CANCER CENTER 2022. [DOI: 10.1016/j.jncc.2022.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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16
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Friedrich T, Scholz M, Durante M. A predictive biophysical model of the combined action of radiotherapy and immunotherapy in cancer. Int J Radiat Oncol Biol Phys 2022; 113:872-884. [DOI: 10.1016/j.ijrobp.2022.03.030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/24/2022] [Accepted: 03/24/2022] [Indexed: 10/18/2022]
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Sung W, Hong TS, Poznansky MC, Paganetti H, Grassberger C. Mathematical Modeling to Simulate the Effect of Adding Radiation Therapy to Immunotherapy and Application to Hepatocellular Carcinoma. Int J Radiat Oncol Biol Phys 2022; 112:1055-1062. [PMID: 34774999 PMCID: PMC9059476 DOI: 10.1016/j.ijrobp.2021.11.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 10/21/2021] [Accepted: 11/07/2021] [Indexed: 02/07/2023]
Abstract
PURPOSE To develop a comprehensive framework to simulate the response to immune checkpoint inhibitors (ICIs) in combination with radiation therapy (RT) and to apply the framework for investigating ICI-RT combination regimen in patients with hepatocellular carcinoma (HCC). METHODS AND MATERIALS The mechanistic mathematical model is based on dynamic biological interactions between the immune system and the tumor using input data from patient blood samples and outcomes of clinical trials. The cell compartments are described by ordinary differential equations and represent irradiated and nonirradiated tumor cells and lymphocytes. The effect of ICI is modeled using an immune activation term that is based on tumor size changes observed in a phase 1/2 clinical trial for HCC. Simulated combination regimen are based on ongoing ICI-RT trials. RESULTS The proposed framework successfully describes tumor volume trajectories observed in early-stage clinical trials of durvalumab monotherapy in patients with HCC. For ICI-RT treatment regimen the irradiated tumor fraction is the most important parameter for the efficacy. For 90% of the tumor cells being irradiated, adding RT to ICI yields an increase in clinical benefit from 33% to 71% in nonirradiated tumor sites. The model agrees with clinical data showing an association of outcome with initial tumor volume and lymphocyte counts. We demonstrate model application in clinical trial design to predict progression-free survival curves, showing that the cohort size to show significant improvement heavily depends on the irradiated tumor fraction. CONCLUSIONS We present a framework extending radiation cell kill models to include circulating lymphocytes and the effect of ICIs and enable simulation of combination strategies. The simulations predict that a significant amount of the benefit from RT in combination with ICI stems from the reduction in irradiated tumor burden and associated immune suppression. This aspect needs to be included in the interpretation of outcomes and the design of novel combination trials.
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Affiliation(s)
- Wonmo Sung
- Division of Biophysics, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts; Department of Biomedical Engineering and Department of Biomedicine and Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Theodore S Hong
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts
| | - Mark C Poznansky
- Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts; Vaccine and Immunotherapy Center, Massachusetts General Hospital, Boston, Massachusetts
| | - Harald Paganetti
- Division of Biophysics, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts
| | - Clemens Grassberger
- Division of Biophysics, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts.
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Xing S, Shin J, Pursley J, Correa-Alfonso CM, Depauw N, Domal S, Withrow J, Bolch W, Grassberger C, Paganetti H. A dynamic blood flow model to compute absorbed dose to circulating blood and lymphocytes in liver external beam radiotherapy. Phys Med Biol 2022; 67:10.1088/1361-6560/ac4da4. [PMID: 35061601 PMCID: PMC8985306 DOI: 10.1088/1361-6560/ac4da4] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 01/21/2022] [Indexed: 01/01/2023]
Abstract
We have developed a novel 4D dynamic liver blood flow model, capable of accurate dose estimation to circulating blood cells during liver-directed external beam radiotherapy, accounting for blood recirculation and radiation delivery time structure. Adult male and adult female liver computational phantoms with detailed vascular trees were developed to include the hepatic arterial, hepatic portal venous, and hepatic venous trees. A discrete time Markov Chain approach was applied to determine the spatiotemporal distribution of 105blood particles (BP) in the human body based on reference values for cardiac output and organ blood volumes. For BPs entering the liver, an explicit Monte Carlo simulation was implemented to track their propagation along ∼2000 distinct vascular pathways through the liver. The model tracks accumulated absorbed dose from time-dependent radiation fields with a 0.1 s time resolution. The computational model was then evaluated for 3 male and 3 female patients receiving photon (VMAT and IMRT) and proton (passive SOBP and active PBS) treatments. The dosimetric impact of treatment modality, delivery time, and fractionation on circulating blood cells was investigated and quantified using the mean dose (μdose,b),V>0Gy,V>0.125Gy,andD2%. Average reductions inμdose,b,V>0Gy,V>0.125GyandD2%of 45%, 6%, 53%, 19% respectively, were observed for proton treatments as compared to photon treatments. Our simulation also showed thatV>0Gy,V>0.125Gy, andD2%were highly sensitive to the beam-on time. BothV>0GyandV>0.125Gyincreased with beam-on time, whereasD2%decreased with increasing beam-on time, demonstrating the tradeoff between low dose to a large fraction of blood cells and high dose to a small fraction of blood cells. Consequently, proton treatments are not necessarily advantageous in terms of dose to the blood simply based on integral dose considerations. Instead, both integral dose and beam-on time can substantially impact relevant dosimetric indices.
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Affiliation(s)
- Shu Xing
- Massachusetts General Hospital, Harvard Medical school, Boston, MA
| | - Jungwook Shin
- Massachusetts General Hospital, Harvard Medical school, Boston, MA,Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD
| | - Jennifer Pursley
- Massachusetts General Hospital, Harvard Medical school, Boston, MA
| | | | - Nicolas Depauw
- Massachusetts General Hospital, Harvard Medical school, Boston, MA
| | - Sean Domal
- Department of Biomedical Engineering, University of Florida, Gainesville, FL
| | - Julia Withrow
- Department of Biomedical Engineering, University of Florida, Gainesville, FL
| | - Wesley Bolch
- Department of Biomedical Engineering, University of Florida, Gainesville, FL
| | | | - Harald Paganetti
- Massachusetts General Hospital, Harvard Medical school, Boston, MA
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19
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Ebrahimi S, Lim G, Liu A, Lin SH, Ellsworth SG, Grassberger C, Mohan R, Cao W. Radiation-Induced Lymphopenia Risks of Photon Versus Proton Therapy for Esophageal Cancer Patients. Int J Part Ther 2021; 8:17-27. [PMID: 34722808 PMCID: PMC8489492 DOI: 10.14338/ijpt-20-00086] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Accepted: 02/02/2021] [Indexed: 12/03/2022] Open
Abstract
Purpose To assess possible differences in radiation-induced lymphocyte depletion for esophageal cancer patients being treated with the following 3 treatment modalities: intensity-modulated radiation therapy (IMRT), passive scattering proton therapy (PSPT), and intensity-modulated proton therapy (IMPT). Methods and Materials We used 2 prediction models to estimate lymphocyte depletion based on dose distributions. Model I used a piecewise linear relationship between lymphocyte survival and voxel-by-voxel dose. Model II assumes that lymphocytes deplete exponentially as a function of total delivered dose. The models can be fitted using the weekly absolute lymphocyte counts measurements collected throughout treatment. We randomly selected 45 esophageal cancer patients treated with IMRT, PSPT, or IMPT at our institution (15 per modality) to demonstrate the fitness of the 2 models. A different group of 10 esophageal cancer patients who had received PSPT were included in this study of in silico simulations of multiple modalities. One IMRT and one IMPT plan were created, using our standards of practice for each modality, as competing plans to the existing PSPT plan for each patient. We fitted the models by PSPT plans used in treatment and predicted absolute lymphocyte counts for IMRT and IMPT plans. Results Model validation on each modality group of patients showed good agreement between measured and predicted absolute lymphocyte counts nadirs with mean squared errors from 0.003 to 0.023 among the modalities and models. In the simulation study of IMRT and IMPT on the 10 PSPT patients, the average predicted absolute lymphocyte count (ALC) nadirs were 0.27, 0.35, and 0.37 K/μL after IMRT, PSPT, and IMPT treatments using Model I, respectively, and 0.14, 0.22, and 0.33 K/μL using Model II. Conclusions Proton plans carried a lower predicted risk of lymphopenia after the treatment course than did photon plans. Moreover, IMPT plans outperformed PSPT in terms of predicted lymphocyte preservation.
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Affiliation(s)
- Saba Ebrahimi
- Department of Industrial Engineering, University of Houston, Houston, TX, USA
| | - Gino Lim
- Department of Industrial Engineering, University of Houston, Houston, TX, USA
| | - Amy Liu
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Steven H Lin
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Clemens Grassberger
- Departments of Radiation Oncology, Massachusetts General Hospital, Boston, MA, USA
| | - Radhe Mohan
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Wenhua Cao
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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20
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Chin RI, Schiff JP, Brenneman RJ, Gay HA, Thorstad WL, Lin AJ. A Rational Approach to Unilateral Neck RT for Head and Neck Cancers in the Era of Immunotherapy. Cancers (Basel) 2021; 13:5269. [PMID: 34771432 PMCID: PMC8582444 DOI: 10.3390/cancers13215269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 10/08/2021] [Accepted: 10/14/2021] [Indexed: 11/16/2022] Open
Abstract
Radiotherapy plays an important role in the definitive and adjuvant treatment of head and neck squamous cell carcinoma (HNSCC). However, standard courses of radiation therapy may contribute to the depletion of circulating lymphocytes and potentially attenuate optimal tumor antigen presentation that may be detrimental to the efficacy of novel immunotherapeutic agents. This review explores the advantages of restricting radiation to the primary tumor/tumor bed and ipsilateral elective neck as it pertains to the evolving field of immunotherapy.
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Affiliation(s)
| | | | | | | | | | - Alexander J. Lin
- Department of Radiation Oncology, Washington University School of Medicine, Saint Louis, MI 63110, USA; (R.-I.C.); (J.P.S.); (R.J.B.); (H.A.G.); (W.L.T.)
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21
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Yoo GS, Yu JI, Cho S, Han Y, Oh Y, Lim DH, Nam HR, Lee JW, Sung KW, Shin HJ. Chronological Analysis of Acute Hematological Outcomes after Proton and Photon Beam Craniospinal Irradiation in Pediatric Brain Tumors. Cancer Res Treat 2021; 54:907-916. [PMID: 34665955 PMCID: PMC9296930 DOI: 10.4143/crt.2021.332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 10/14/2021] [Indexed: 12/02/2022] Open
Abstract
Purpose This study aimed to compare the early hematological dynamics and acute toxicities between proton beam craniospinal irradiation (PrCSI) and photon beam craniospinal irradiation (PhCSI) for pediatric brain tumors. Materials and Methods We retrospectively reviewed patients with pediatric brain tumors who received craniospinal irradiation (CSI). The average change in hemoglobin levels (ΔHbavg), absolute lymphocyte counts (ΔALCavg), and platelet counts (ΔPLTavg) from baseline values was evaluated and compared between the PrCSI and PhCSI groups at 1 and 2 weeks after the initiation of CSI, 1 week before and at the end of radiotherapy, and 3–4 weeks after the completion of radiotherapy using t-test and mixed-model analysis. Results The PrCSI and PhCSI groups consisted of 36 and 30 patients, respectively. There were no significant differences in ΔHbavg between the two groups at any timepoint. However, ΔALCavg and ΔPLTavg were significantly lower in the PhCSI group than in PrCSI group at every timepoint, demonstrating that PrCSI resulted in a significantly lower rate of decline and better recovery of absolute lymphocyte and platelet counts. The rate of grade 3 acute anemia was significantly lower in the PrCSI group than in in the PhCSI group. Conclusion PrCSI showed a lower rate of decline and better recovery of absolute lymphocyte and platelet counts than PhCSI in the CSI for pediatric brain tumors. Grade 3 acute anemia was significantly less frequent in the PrCSI group than in the PhCSI group. Further large-scale studies are warranted to confirm these results.
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Affiliation(s)
- Gyu Sang Yoo
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jeong Il Yu
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sungkoo Cho
- Department of Radiation Oncology, Samsung Medical Center, Seoul, Korea
| | - Youngyih Han
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yoonjin Oh
- Department of Radiation Oncology, Samsung Medical Center, Seoul, Korea
| | - Do Hoon Lim
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hee Rim Nam
- Department of Radiation Oncology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Ji-Won Lee
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Ki-Woong Sung
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hyung Jin Shin
- Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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22
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Chen F, Yu H, Zhang H, Nong Y, Wang Q, Jing H, Han Y, Wu J, Zhou Z, Yang L, Xu Z, Liu Y, Fu P, Jin JY, Hsue V, Chang A, Kong FMS. Risk factors for radiation induced lymphopenia in patients with breast cancer receiving adjuvant radiotherapy. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:1288. [PMID: 34532425 PMCID: PMC8422134 DOI: 10.21037/atm-21-2150] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 06/25/2021] [Indexed: 12/31/2022]
Abstract
Background This study aimed to investigate radiation-induced lymphopenia and its potential risk factors in patients with breast cancer receiving adjuvant radiotherapy. Methods Breast cancer patients received adjuvant radiotherapy (RT) at our hospital with peripheral lymphocyte counts (PLC) at pre-and immediately after RT (post-RT) were eligible. The primary endpoints were any grade of lymphopenia post-RT and nadir-PLC/pre-PLC <0.8. Patient characteristics, tumor factors, and treatment factors were collected for risk assessment. Data are presented as mean and 95% confidence interval (CI) unless otherwise specified. Matched analysis was used to compare the statistical significance between different RT techniques. Results A total of 735 consecutive patients met the study criteria. The mean PLC was 1.58×109/L before and 0.99×109/L post-RT (P<0.001). At the end of RT, 60.5% of patients had lymphopenia. Univariate and multivariable logistic analyses showed that RT technique involving RapidArc, mean lung dose, and chemotherapy were significant risk factors (P<0.05) for lymphopenia. RT technique was the only significant risk factor (P<0.05) for nadir-PLC/pre-PLC <0.8. Patients treated with RapidArc had a significantly greater reduction of PLC along with greater V5 of the lungs, even after matching mean lung dose and radiated volume. Conclusions Lymphopenia is common in patients with breast cancer after adjuvant RT. RT technique is the only significant factor for lymphopenia and nadir-PLC/pre-PLC <0.8, suggesting the significance of RT technique choice to minimize lymphopenia and improve treatment outcomes.
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Affiliation(s)
- Fang Chen
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Hao Yu
- Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Hong Zhang
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Yaqing Nong
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Qian Wang
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Haiman Jing
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Ying Han
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Junjie Wu
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Zheng Zhou
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Li Yang
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Zhiyuan Xu
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Yaya Liu
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Pingfu Fu
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, Cleveland, OH, USA
| | - Jian-Yue Jin
- Department of Radiation Oncology, Case Western Reserve University, Cleveland, OH, USA
| | - Victor Hsue
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Amy Chang
- Comprehensive Oncology Center, Hong Kong Sanatorium & Hospital, Hong Kong, China
| | - Feng-Ming Spring Kong
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China.,Department of Clinical Oncology, Hong Kong University Li Ka Shing Medical School, Hong Kong, China
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23
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Shin J, Xing S, McCullum L, Hammi A, Pursley J, Correa CA, Withrow J, Domal S, Bolch W, Paganetti H, Grassberger C. HEDOS-a computational tool to assess radiation dose to circulating blood cells during external beam radiotherapy based on whole-body blood flow simulations. Phys Med Biol 2021; 66:10.1088/1361-6560/ac16ea. [PMID: 34293735 PMCID: PMC8720566 DOI: 10.1088/1361-6560/ac16ea] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 07/22/2021] [Indexed: 11/11/2022]
Abstract
We have developed a time-dependent computational framework, hematological dose (HEDOS), to estimate dose to circulating blood cells from radiation therapy treatment fields for any treatment site. Two independent dynamic models were implemented in HEDOS: one describing the spatiotemporal distribution of blood particles (BPs) in organs and the second describing the time-dependent radiation field delivery. A whole-body blood flow network based on blood volumes and flow rates from ICRP Publication 89 was simulated to produce the spatiotemporal distribution of BPs in organs across the entire body using a discrete-time Markov process. Constant or time-varying transition probabilities were applied and their impact on transition time was investigated. The impact of treatment time and anatomical site were investigated using imaging data and dose distributions from a liver cancer and a brain cancer patient. The simulations revealed different dose levels to the circulating blood for brain irradiation compared to liver irradiation even for similar field sizes due to the different blood flow properties of the two organs. The volume of blood receiving any dose (V>0 Gy) after a single radiation fraction increases from 1.2% for a 1 s delivery time to 20.9% for 120 s delivery time for the brain cancer treatment, and from 10% (1 s) to 48.7% (120 s) for a liver cancer treatment. Other measures of the low-dose bath to the circulating blood such as the dose to small volumes of blood (D2%) decreases with longer delivery time. Furthermore, we demonstrate that the blood dose-volume histogram is highly sensitive to changes in the treatment time, indicating that dynamic modeling of blood flow and radiation fields is necessary to evaluate dose to circulating blood cells for the assessment of radiation-induced lymphopenia. HEDOS is publicly available and allows for the estimation of patient-specific dose to circulating blood cells based on organ DVHs, thus enabling the study of the impact of different treatment plans, dose rates, and fractionation schemes.
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Affiliation(s)
- Jungwook Shin
- Division of Radiation Biophysics, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Shu Xing
- Division of Radiation Biophysics, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Lucas McCullum
- Division of Radiation Biophysics, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Abdelkhalek Hammi
- Division of Radiation Biophysics, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Jennifer Pursley
- Division of Radiation Biophysics, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Camilo A Correa
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States of America
| | - Julia Withrow
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States of America
| | - Sean Domal
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States of America
| | - Wesley Bolch
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States of America
| | - Harald Paganetti
- Division of Radiation Biophysics, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Clemens Grassberger
- Division of Radiation Biophysics, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
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Radiotherapy planning parameters correlate with changes in the peripheral immune status of patients undergoing curative radiotherapy for localized prostate cancer. Cancer Immunol Immunother 2021; 71:541-552. [PMID: 34269847 PMCID: PMC8854140 DOI: 10.1007/s00262-021-03002-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 06/28/2021] [Indexed: 12/12/2022]
Abstract
Purpose The influence of radiotherapy on patient immune cell subsets has been established by several groups. Following a previously published analysis of immune changes during and after curative radiotherapy for prostate cancer, this analysis focused on describing correlations of changes of immune cell subsets with radiation treatment parameters. Patients and methods For 13 patients treated in a prospective trial with radiotherapy to the prostate region (primary analysis) and five patients treated with radiotherapy to prostate and pelvic nodal regions (exploratory analysis), already published immune monitoring data were correlated with clinical data as well as radiation planning parameters such as clinical target volume (CTV) and volumes receiving 20 Gy (V20) for newly contoured volumes of pelvic blood vessels and bone marrow. Results Most significant changes among immune cell subsets were observed at the end of radiotherapy. In contrast, correlations of age and CD8+ subsets (effector and memory cells) were observed early during and 3 months after radiotherapy. Ratios of T cells and T cell proliferation compared to baseline correlated with CTV. Early changes in regulatory T cells (Treg cells) and CD8+ effector T cells correlated with V20 of blood vessels and bone volumes. Conclusions Patient age as well as radiotherapy planning parameters correlated with immune changes during radiotherapy. Larger irradiated volumes seem to correlate with early suppression of anti-cancer immunity. For immune cell analysis during normofractionated radiotherapy and correlations with treatment planning parameters, different time points should be looked at in future projects. Trial registration number: NCT01376674, 20.06.2011 Supplementary Information The online version contains supplementary material available at 10.1007/s00262-021-03002-6.
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25
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Friedrich T, Henthorn N, Durante M. Modeling Radioimmune Response-Current Status and Perspectives. Front Oncol 2021; 11:647272. [PMID: 33796470 PMCID: PMC8008061 DOI: 10.3389/fonc.2021.647272] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 02/25/2021] [Indexed: 12/13/2022] Open
Abstract
The combination of immune therapy with radiation offers an exciting and promising treatment modality in cancer therapy. It has been hypothesized that radiation induces damage signals within the tumor, making it more detectable for the immune system. In combination with inhibiting immune checkpoints an effective anti-tumor immune response may be established. This inversion from tumor immune evasion raises numerous questions to be solved to support an effective clinical implementation: These include the optimum immune drug and radiation dose time courses, the amount of damage and associated doses required to stimulate an immune response, and the impact of lymphocyte status and dynamics. Biophysical modeling can offer unique insights, providing quantitative information addressing these factors and highlighting mechanisms of action. In this work we review the existing modeling approaches of combined ‘radioimmune’ response, as well as associated fields of study. We propose modeling attempts that appear relevant for an effective and predictive model. We emphasize the importance of the time course of drug and dose delivery in view to the time course of the triggered biological processes. Special attention is also paid to the dose distribution to circulating blood lymphocytes and the effect this has on immune competence.
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Affiliation(s)
- Thomas Friedrich
- Biophysics Department, GSI Helmholtz Center for Heavy Ion Research, Darmstadt, Germany
| | - Nicholas Henthorn
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom.,The Christie NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Marco Durante
- Biophysics Department, GSI Helmholtz Center for Heavy Ion Research, Darmstadt, Germany.,Institute for Solid State Physics, Technical University Darmstadt, Darmstadt, Germany
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Abravan A, Faivre-Finn C, Kennedy J, McWilliam A, van Herk M. Radiotherapy-Related Lymphopenia Affects Overall Survival in Patients With Lung Cancer. J Thorac Oncol 2020; 15:1624-1635. [PMID: 32553694 DOI: 10.1016/j.jtho.2020.06.008] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 06/10/2020] [Accepted: 06/11/2020] [Indexed: 01/10/2023]
Abstract
INTRODUCTION Lymphopenia after radiotherapy has an adverse effect on the patient's outcome. However, the relationship between radiotherapy dose delivery and lymphopenia is not fully understood. This work used image-based data mining to identify anatomical regions where the received dose is correlated with severe lymphopenia. METHODS A total of 901 patients with lung cancer were analyzed. A Cox model was used to assess prognostic factors of overall survival (OS). Two matched groups were defined-patients with lymphopenia of grade 3 or higher and patients without lymphopenia of grade 3-based on tumor volume, baseline lymphocytes, and prescribed dose. Then, data mining was used to identify regions where dose correlates significantly with lymphopenia of grade 3 or higher. For this, dose matrices were aligned using registration of the computed tomography images to one reference patient. Mean dose distributions were obtained for the two groups, and organs of significance were detected. Dosimetric parameters from the identified organs that had the highest correlation with lymphocytes at nadir were selected. Multivariable analysis was conducted for lymphopenia of grade 3 or higher on the full lung cohort, and the model was tested on 305 patients with esophageal cancer. RESULTS Adjusted Cox regression revealed that lymphopenia of grade 3 or higher is an independent factor of OS. The anatomical regions identified were the heart, lung, and thoracic vertebrae. Dosimetric parameters for lymphopenia included thoracic vertebrae V20, mean lung dose, and mean heart dose, which were further validated in the esophageal cancer cohort. CONCLUSIONS We report that severe lymphopenia during radiotherapy is a poor prognostic factor for OS in patients with lung cancer and could be mitigated by minimizing thoracic vertebrae V20, mean lung dose, and mean heart dose to limit the irradiation of stem cells and blood pool.
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Affiliation(s)
- Azadeh Abravan
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom; Radiotherapy Related Research, The Christie NHS Foundation Trust, Manchester, United Kingdom.
| | - Corinne Faivre-Finn
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom; Radiotherapy Related Research, The Christie NHS Foundation Trust, Manchester, United Kingdom
| | - Jason Kennedy
- Radiotherapy Related Research, The Christie NHS Foundation Trust, Manchester, United Kingdom
| | - Alan McWilliam
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom; Radiotherapy Related Research, The Christie NHS Foundation Trust, Manchester, United Kingdom
| | - Marcel van Herk
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom; Radiotherapy Related Research, The Christie NHS Foundation Trust, Manchester, United Kingdom
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27
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McWilliam A, Khalifa J, Vasquez Osorio E, Banfill K, Abravan A, Faivre-Finn C, van Herk M. Novel Methodology to Investigate the Effect of Radiation Dose to Heart Substructures on Overall Survival. Int J Radiat Oncol Biol Phys 2020; 108:1073-1081. [PMID: 32585334 DOI: 10.1016/j.ijrobp.2020.06.031] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 05/18/2020] [Accepted: 06/17/2020] [Indexed: 12/25/2022]
Abstract
PURPOSE For patients with lung cancer treated with radiation therapy, a dose to the heart is associated with excess mortality; however, it is often not feasible to spare the whole heart. Our aim is to define cardiac substructures and dose thresholds that optimally reduce early mortality. METHODS AND MATERIALS Fourteen cardiac substructures were delineated on 5 template patients with representative anatomies. One thousand one hundred sixty-one patients with non-small cell lung cancer were registered nonrigidly to these 5 template anatomies, and their radiation therapy doses were mapped. Mean and maximum dose to each substructure were extracted, and the means were evaluated as input to prediction models. The cohort was bootstrapped into 2 variable reduction techniques: elastic net least absolute shrinkage and selection operator and the random survival forest model. Each method was optimized to extract variables contributing most to overall survival, and model coefficients were evaluated to select these substructures. The most important variables common to both models were selected and evaluated in multivariable Cox-proportional hazard models. A threshold dose was defined, and Kaplan-Meier survival curves plotted. RESULTS Nine hundred seventy-eight patients remained after visual quality assurance of the registration. Ranking the model coefficients across the bootstraps selected the maximum dose to the right atrium, right coronary artery, and ascending aorta as the most important factors associated with survival. The maximum dose to the combined cardiac region showed significance in the multivariable model, a hazard ratio of 1.01/Gy, and P = .03 after accounting for tumor volume (P < .001), N stage (P < .01), and performance status (P = .01). The optimal threshold for the maximum dose, equivalent dose in 2-Gy fractions, was 23 Gy. Kaplan-Meier survival curves showed a significant split (log-rank P = .008). CONCLUSIONS The maximum dose to the combined cardiac region encompassing the right atrium, right coronary artery, and ascending aorta was found to have the greatest effect on patient survival. A maximum equivalent dose in 2-Gy fractions of 23 Gy was identified for consideration as a dose limit in future studies.
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Affiliation(s)
- Alan McWilliam
- Division of Clinical Cancer Science, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Department of Radiotherapy Related Research, The Christie NHS Foundation Trust, Manchester, United Kingdom.
| | - Jonathan Khalifa
- Department of Radiation Oncology, Institut Universitaire du Cancer de Toulouse, Toulouse, France
| | - Eliana Vasquez Osorio
- Division of Clinical Cancer Science, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Department of Radiotherapy Related Research, The Christie NHS Foundation Trust, Manchester, United Kingdom
| | - Kathryn Banfill
- Division of Clinical Cancer Science, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Department of Radiotherapy Related Research, The Christie NHS Foundation Trust, Manchester, United Kingdom
| | - Azadeh Abravan
- Division of Clinical Cancer Science, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Department of Radiotherapy Related Research, The Christie NHS Foundation Trust, Manchester, United Kingdom
| | - Corinne Faivre-Finn
- Division of Clinical Cancer Science, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Department of Radiotherapy Related Research, The Christie NHS Foundation Trust, Manchester, United Kingdom
| | - Marcel van Herk
- Division of Clinical Cancer Science, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Department of Radiotherapy Related Research, The Christie NHS Foundation Trust, Manchester, United Kingdom
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28
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Jin JY, Gu A, Wang W, Oleinick NL, Machtay M, Spring Kong FM. Ultra-high dose rate effect on circulating immune cells: A potential mechanism for FLASH effect? Radiother Oncol 2020; 149:55-62. [PMID: 32387486 DOI: 10.1016/j.radonc.2020.04.054] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 04/28/2020] [Accepted: 04/29/2020] [Indexed: 12/28/2022]
Abstract
PURPOSE "FLASH" radiotherapy (RT) is a potential paradigm-changing RT technology with marked tumor killing and normal tissue sparing. However, the mechanism of the FLASH effect is not well understood. We hypothesize that the ultra-high dose rate FLASH-RT significantly reduces the killing of circulating immune cells which may partially contribute to the reported FLASH effect. METHODS This computation study directly models the effect of radiation dose rate on the killing of circulating immune cells. The model considers an irradiated volume that takes up A% of cardiac output and contains B% of total blood. The irradiated blood volume and dose were calculated for various A%, B%, blood circulation time, and irradiation time (which depends on the dose rate). The linear-quadratic model was used to calculate the extent of killing of circulating immune cells at ultra-high vs. conventional dose rates. RESULTS A strong sparing effect on circulating blood cells by FLASH-RT was noticed; i.e., killing of circulating immune cells reduced from 90% to 100% at conventional dose rates to 5-10% at ultra-high dose rates. The threshold FLASH dose rate was determined to be ~40 Gy/s for mice in an average situation (A% = 50%), consistent with the reported FLASH dose rate in animal studies, and it was approximately one order of magnitude lower for humans than for mice. The magnitude of this sparing effect increased with the dose/fraction, reached a plateau at 30-50 Gy/fraction, and almost completely vanished at 2 Gy/fraction. CONCLUSION We have calculated a strong sparing effect on circulating immune cells by FLASH-RT, which may contribute to the reported FLASH effects in animal studies.
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Affiliation(s)
- Jian-Yue Jin
- Department of Radiation Oncology, University Hospitals, Cleveland Medical Center, United States; Department of Radiation Oncology, Case Western Reserve University School of Medicine, Cleveland, United States.
| | - Anxin Gu
- Department of Radiation Oncology, Case Western Reserve University School of Medicine, Cleveland, United States; Department of Radiation Oncology, Harbin Medical University Cancer Hospital, China
| | - Weili Wang
- Department of Radiation Oncology, Case Western Reserve University School of Medicine, Cleveland, United States
| | - Nancy L Oleinick
- Department of Radiation Oncology, Case Western Reserve University School of Medicine, Cleveland, United States
| | - Mitchell Machtay
- Department of Radiation Oncology, University Hospitals, Cleveland Medical Center, United States; Department of Radiation Oncology, Case Western Reserve University School of Medicine, Cleveland, United States
| | - Feng-Ming Spring Kong
- Department of Radiation Oncology, University Hospitals, Cleveland Medical Center, United States; Department of Radiation Oncology, Case Western Reserve University School of Medicine, Cleveland, United States; Departments of Clinical Oncology, Hong Kong University Shenzhen Hospital, and Hong Kong University, Hong Kong, China
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29
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Holub K, Vargas A, Biete A. Radiation-induced lymphopenia: the main aspects to consider in immunotherapy trials for endometrial and cervical cancer patients. Clin Transl Oncol 2020; 22:2040-2048. [PMID: 32285291 DOI: 10.1007/s12094-020-02345-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 03/19/2020] [Indexed: 01/10/2023]
Abstract
BACKGROUND Although the chemotherapy-induced depletion of circulating white blood cells (WBC) is well recognized, the impact of exclusive radiotherapy (RT) on the different subpopulations of WBC remains unexplored. This may be important for immunotherapy administrated in combination with radiation, especially in malignant tumors usually treated with RT or chemoradiotherapy (CRT), and characterized by a high mutational burden, such as endometrial (EC) or cervical cancer (CC). We aimed to evaluate the impact of RT and CRT on circulating WBC in uterine cancers and its correlation with survival. MATERIAL AND METHODS A total of 202 consecutive patients with uterine cancers treated with RT or CRT between 2009 and 2016 in a large European center and with available basal and post-treatment blood tests were retrospectively evaluated. EC and CC patients were analyzed separately. The differences between pre- and post- treatment WBC mean values were evaluated independently in patients treated with CRT and exclusive RT. Two-sided T test for paired samples and Kaplan-Meier curves were applied for analysis (p value < 0.05, SPSS v.23). RESULTS Among EC patients, 29 received CRT and 34 exclusive postoperative RT, while in CC cohort, 105 were treated with CRT and 34 with RT. In both cohorts, CRT affected significantly all WBC subtypes, whereas exclusive RT decreased only lymphocytes population (p = 0.000). Radiation-induced lymphopenia (RIL) had no impact on survival outcomes. CONCLUSIONS The selective depletion of lymphocytes after RT was significant in both EC and CC. Our results are of interest for further research on RIL and for design of immunotherapy-based clinical trials.
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Affiliation(s)
- K Holub
- Radiotherapy Department, Gustave Roussy Cancer Campus, Villejuif, France. .,Radiation Oncology Department, Hospital Clinic de Barcelona, University of Barcelona, Barcelona, Spain.
| | - A Vargas
- Radiation Oncology Department, Hospital Clinic de Barcelona, University of Barcelona, Barcelona, Spain.,Department of Radiation Oncology, Clínica Instituto de Radiomedicina (IRAM), Santiago de Chile, Chile
| | - A Biete
- Radiation Oncology Department, Hospital Clinic de Barcelona, University of Barcelona, Barcelona, Spain
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30
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Sun GY, Wang SL, Song YW, Jin J, Wang WH, Liu YP, Ren H, Fang H, Tang Y, Zhao XR, Song YC, Yu ZH, Liu XF, Li YX. Radiation-Induced Lymphopenia Predicts Poorer Prognosis in Patients With Breast Cancer: A Post Hoc Analysis of a Randomized Controlled Trial of Postmastectomy Hypofractionated Radiation Therapy. Int J Radiat Oncol Biol Phys 2020; 108:277-285. [PMID: 32147519 DOI: 10.1016/j.ijrobp.2020.02.633] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Revised: 02/17/2020] [Accepted: 02/22/2020] [Indexed: 01/05/2023]
Abstract
PURPOSE The aim of this study was to determine whether radiation-induced lymphopenia affects the survival of patients with breast cancer. METHODS AND MATERIALS Post hoc analysis was conducted on data from 598 patients with breast cancer from a randomized controlled trial comparing postmastectomy hypofractionated radiation therapy (HFRT; 43.5 Gy in 15 fractions over 3 weeks) with conventional fractionated radiation therapy (CFRT; 50 Gy in 25 fractions over 5 weeks). Mean peripheral lymphocyte count (PLC) at different time points in the 2 groups was compared by the t test. Disease-free survival and overall survival were analyzed by the Kaplan-Meier method and compared between groups by the log-rank test. RESULTS Baseline PLC (pre-PLC) was comparable between HFRT and CFRT patients (1.60 ± 0.57 × 109/L vs 1.56 ± 0.52 × 109/L; P = .33). In both groups, the PLC declined steadily during the course of radiation therapy but started to recover at 1 month after radiation therapy. Incidence of lymphopenia was significantly lower in HFRT patients (45.4% vs 55.7%; P = .01). Nadir-PLC was significantly higher in HFRT patients (1.08 ± 0.37 × 109/L vs 0.97 ± 0.31× 109/L; P < .001), as was the nadir-PLC/pre-PLC ratio (0.72 ± 0.28 vs 0.67 ± 0.28; P = .02). Median follow-up was 57.6 months (interquartile range, 38.5-81.4). The 5-year disease-free survival was significantly lower in patients with a nadir-PLC/pre-PLC ratio <0.8 than in those with a ratio ≥0.8 (71.8% vs 82.6%; P = .01); however, overall survival was comparable between the groups (85.8% vs 90.6%; P = .24). CONCLUSIONS The risk of radiation-induced lymphopenia in patients with breast cancer is lower with HFRT than with CFRT. A low nadir-PLC/pre-PLC ratio may predict poor prognosis.
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Affiliation(s)
- Guang-Yi Sun
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Shu-Lian Wang
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
| | - Yong-Wen Song
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jing Jin
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Wei-Hu Wang
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yue-Ping Liu
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Hua Ren
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Hui Fang
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yu Tang
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xu-Ran Zhao
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yu-Chun Song
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Zi-Hao Yu
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xin-Fan Liu
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Ye-Xiong Li
- Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
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