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Comprehensive geriatric assessment predicts radiation-induced acute toxicity in prostate cancer patients. Strahlenther Onkol 2024; 200:208-218. [PMID: 37658924 PMCID: PMC10876759 DOI: 10.1007/s00066-023-02132-3] [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: 06/09/2023] [Accepted: 07/27/2023] [Indexed: 09/05/2023]
Abstract
PURPOSE The purpose of the present prospective study was to evaluate the significance of geriatric conditions measured by a comprehensive geriatric assessment (GA) for the prediction of the risk of high-grade acute radiation-induced toxicity. METHODS A total of 314 prostate cancer patients (age ≥ 65 years) undergoing definitive radiotherapy at a tertiary academic center were included. Prior to treatment, patients underwent a GA. High-grade toxicity was defined as acute toxicity grade ≥ 2 according to standard RTOG/EORTC criteria. To analyze the predictive value of the GA, univariable and multivariable logistic regression models were applied. RESULTS A total of 40 patients (12.7%) developed acute toxicity grade ≥ 2; high grade genitourinary was found in 37 patients (11.8%) and rectal toxicity in 8 patients (2.5%), respectively. Multivariable analysis revealed a significant association of comorbidities with overall toxicity grade ≥ 2 (odds ratio [OR] 2.633, 95% confidence interval [CI] 1.260-5.502; p = 0.010) as well as with high-grade genitourinary and rectal toxicity (OR 2.169, 95%CI1.017-4.625; p = 0.045 and OR 7.220, 95%CI 1.227-42.473; p = 0.029, respectively). Furthermore, the Activities of Daily Living score (OR 0.054, 95%CI 0.004-0.651; p = 0.022), social status (OR 0.159, 95%CI 0.028-0.891; p = 0.036), and polypharmacy (OR 4.618, 95%CI 1.045-20.405; p = 0.044) were identified as independent predictors of rectal toxicity grade ≥ 2. CONCLUSION Geriatric conditions seem to be predictive of the development of high-grade radiation-induced toxicity in prostate cancer patients treated with definitive radiotherapy.
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Interobserver agreement on definition of the target volume in stereotactic radiotherapy for pancreatic adenocarcinoma using different imaging modalities. Strahlenther Onkol 2023; 199:973-981. [PMID: 37268767 PMCID: PMC10598103 DOI: 10.1007/s00066-023-02085-7] [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: 12/30/2022] [Accepted: 04/11/2023] [Indexed: 06/04/2023]
Abstract
PURPOSE The aim of this study was to evaluate interobserver agreement (IOA) on target volume definition for pancreatic cancer (PACA) within the Radiosurgery and Stereotactic Radiotherapy Working Group of the German Society of Radiation Oncology (DEGRO) and to identify the influence of imaging modalities on the definition of the target volumes. METHODS Two cases of locally advanced PACA and one local recurrence were selected from a large SBRT database. Delineation was based on either a planning 4D CT with or without (w/wo) IV contrast, w/wo PET/CT, and w/wo diagnostic MRI. Novel compared to other studies, a combination of four metrics was used to integrate several aspects of target volume segmentation: the Dice coefficient (DSC), the Hausdorff distance (HD), the probabilistic distance (PBD), and the volumetric similarity (VS). RESULTS For all three GTVs, the median DSC was 0.75 (range 0.17-0.95), the median HD 15 (range 3.22-67.11) mm, the median PBD 0.33 (range 0.06-4.86), and the median VS was 0.88 (range 0.31-1). For ITVs and PTVs the results were similar. When comparing the imaging modalities for delineation, the best agreement for the GTV was achieved using PET/CT, and for the ITV and PTV using 4D PET/CT, in treatment position with abdominal compression. CONCLUSION Overall, there was good GTV agreement (DSC). Combined metrics appeared to allow a more valid detection of interobserver variation. For SBRT, either 4D PET/CT or 3D PET/CT in treatment position with abdominal compression leads to better agreement and should be considered as a very useful imaging modality for the definition of treatment volumes in pancreatic SBRT. Contouring does not appear to be the weakest link in the treatment planning chain of SBRT for PACA.
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What MRI Sequences are Necessary for Automated Neural Network-Based Metastasis Segmentation - An Ablation Study. Int J Radiat Oncol Biol Phys 2023; 117:e704-e705. [PMID: 37786065 DOI: 10.1016/j.ijrobp.2023.06.2195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Brain metastasis (BM) delineation is a time-consuming process in both daily clinical practice and research. Automated BM segmentation algorithms can be used to assist in this task. Most approaches to brain tumor segmentation, such as algorithms trained on the BraTS challenge, use four magnetic resonance imaging (MRI) sequences as input, making them susceptible to missing or corrupted sequences and increase the number of sequences necessary for MRI RT planning. The goal of this project is to compare neural networks with different combinations of input sequences for the segmentation of the contrast-enhancing metastasis and the surrounding FLAIR hyperintense edema. All models were tested in a multicenter international external test cohort. This allows us to determine which MRI sequences are needed for effective automated segmentations. MATERIALS/METHODS In total, we had T1-weighted sequences without (T1) and with contrast enhancement (T1-CE), T2-weighted sequences (T2), and T2 fluid-attenuated inversion recovery (FLAIR) sequences from 339 patients with at least one brain metastasis from seven centers available. Preprocessing yielded co-registered, skull-stripped sequences with an isotropic resolution of 1 millimeter. The contrast-enhancing metastasis as well as the surrounding FLAIR hyperintense edema were manually segmented to create reference labels. A baseline 3D U-Net with all four sequences as well as six additional U-Nets with different clinically plausible combinations (T1-CE; T1; FLAIR; T1-CE+FLAIR; T1-CE+T1+FLAIR; T1-CE+T1) of input sequences were trained on a cohort of 239 patients from two centers and subsequently tested on an external cohort of 100 patients from the remaining five centers. RESULTS All models that included T1-CE in their selected sequences showed similar performance for metastasis segmentation with a median Dice similarity coefficient (DSC) of 0.93-0.96. T1-CE alone likewise achieved a performance of 0.96 (IQR 0.93-0.97). The model trained with only FLAIR performed worse (DSC = 0.73, IQR 0.54-0.84). For edema segmentation, models that included both T1-CE and FLAIR performed best (median DSC = 0.93), while the remaining four models without simultaneous inclusion of these two sequences (T1-CE; T1; FLAIR; T1-CE+T1) reached a median DSC of 0.81-0.89. CONCLUSION Automatic segmentation of brain metastases with less than four input sequences is feasible with minimal or no loss of quality. A T1-CE-only protocol suffices for metastasis segmentation. In contrast, for edema segmentation, the combination of T1-CE and FLAIR seems to be important. Missing either T1-CE or FLAIR decreases performance. These findings may improve future imaging routines by omitting unnecessary sequences, thus speeding up procedures in daily clinical practice while allowing for optimal neural network-based target definitions.
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Abstract
BACKGROUND The clinical target volume (CTV) is regarded fundamental for radiotherapy planning by the International Commission on Radiation Units and Measurements (ICRU). OBJECTIVES The aim of this article is to give an overview on the basics and problems of defining the CTV for radiotherapy planning. MATERIALS AND METHODS After briefly defining CTV, a short description of the process to homogenize CTV in intraindividual comparisons is given, where special attention is paid to radiological requirements. This information is summarized in a number of tables. RESULTS CTV is the most complex volume among the target volumes that have been defined by the ICRU. A survey of the determinants of the definition of CTV is given. CONCLUSIONS This overview on the basic rules of how to define CTVs can help to increase the understanding of the radiological requirements for optimum imaging to support radiotherapy planning regardless of the specialty of the physician.
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Stereotactic Body Radiation Therapy as an Alternative Treatment for Patients with Hepatocellular Carcinoma Compared to Sorafenib: A Propensity Score Analysis. Liver Cancer 2019; 8:281-294. [PMID: 31602371 PMCID: PMC6738268 DOI: 10.1159/000490260] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 05/20/2018] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND AND AIMS Stereotactic body radiation therapy (SBRT) has emerged as a safe and effective treatment for patients with hepatocellular carcinoma (HCC), but its role in patients with advanced HCC is not yet defined. In this study, we aim to assess the efficacy and safety of SBRT in comparison to sorafenib treatment in patients with advanced HCC. METHODS We included 901 patients treated with sorafenib at six tertiary centers in Europe and Asia and 122 patients treated with SBRT from 13 centers in Germany and Switzerland. Medical records were reviewed including laboratory parameters, treatment characteristics and development of adverse events. Propensity score matching was performed to adjust for differences in baseline characteristics. The primary endpoint was overall survival (OS) and progression-free survival. RESULTS Median OS of SBRT patients was 18.1 (10.3-25.9) months compared to 8.8 (8.2-9.5) in sorafenib patients. After adjusting for different baseline characteristics, the survival benefit for patients treated with SBRT was still preserved with a median OS of 17.0 (10.8-23.2) months compared to 9.6 (8.6-10.7) months in sorafenib patients. SBRT treatment of intrahepatic lesions in patients with extrahepatic metastases was also associated with improved OS compared to patients treated with sorafenib in the same setting (17.0 vs. 10.0 months, p = 0.012), whereas in patients with portal vein thrombosis there was no survival benefit in patients with SBRT. CONCLUSIONS In this retrospective comparative study, SBRT showed superior efficacy in HCC patients compared to patients treated with sorafenib.
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Repeated SBRT for in- and out-of-field recurrences in the liver. Strahlenther Onkol 2018; 195:246-253. [DOI: 10.1007/s00066-018-1385-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 10/09/2018] [Indexed: 12/21/2022]
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Stereotactic body radiotherapy (SBRT) for locally advanced intrahepatic and extrahepatic cholangiocarcinoma. BMC Cancer 2017; 17:781. [PMID: 29162055 PMCID: PMC5699184 DOI: 10.1186/s12885-017-3788-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 11/15/2017] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND To evaluate the role of ablative radiotherapy doses in the treatment of hilar or intrahepatic cholangiocarcinoma (CCC) using stereotactic body radiotherapy (SBRT). METHODS Consecutive patients treated from 2007 to 2016 with CCC were evaluated. Local control and toxicities were assessed every 3 months according to the Response Evaluation Criteria In Solid Tumors (RECIST) and the Common Terminology Criteria for Adverse Events v4.0, respectively. Overall survival (OS), local control (LC) and progression free survival were calculated from SBRT. RESULTS Thirty seven patients with 43 lesions were retrospectively evaluated. The median dose delivered was 45 Gy (range 25-66 Gy) in 3-12 fractions, corresponding to a median equivalent dose in 2 Gy fractions (EQD210) of 56 (range 25-85) Gy. The median follow up was 24 months. The OS at 1 year was 56% with a median OS of 14 (95% CI: 7.8-20.2) months from start of SBRT and 22 (95% CI: 17.5-26.5) months from diagnosis. Eight lesions progressed locally. The local control rate (LC) at 1 year was 78%. The median progression free survival was 9 months (95% CI 2.8-15.2) 21 patients progressed in the liver but out of field and 15 progressed distantly. SBRT was well tolerated. Three patients (9%) developed a Grade III bleeding. Seven patients developed a cholangitis, one due to progression and the other because of a stent dysfunction 2-21(median 8) months from SBRT. CONCLUSION In patients with locally advanced cholangiocarcinoma, SBRT is a local treatment option with an acceptable toxicity profile which warrants further investigation in prospective trials.
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Is serum level of CC chemokine ligand 18 a biomarker for the prediction of radiation induced lung toxicity (RILT)? PLoS One 2017; 12:e0185350. [PMID: 28957436 PMCID: PMC5619767 DOI: 10.1371/journal.pone.0185350] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 09/11/2017] [Indexed: 12/17/2022] Open
Abstract
The CC chemokine ligand 18 (CCL18) is produced by alveolar macrophages in patients with fibrosing lung disease and its concentration is increased in various fibrotic lung diseases. Furthermore CCL18 is elevated in several malignancies as it is produced by tumor associated macrophages. In this study we aimed to analyze the role of CCL18 as a prognostic biomarker for the development of early radiation induced lung toxicity (RILT), i.e. radiation pneumonitis after thoracic irradiation and its significance in the course of the disease. Sixty seven patients were enrolled prospectively in the study. Patients were treated with irradiation for several thoracic malignancies (lung cancer, esophageal cancer, thymoma), either with conventionally fractionated or hypo-fractionated radiotherapy. The CCL18 serum levels were quantified with ELISA (enzyme-linked immunosorbent assay) at predefined time points: before, during and at the end of treatment as well as in the first and second follow-up. Treatment parameters and functional tests were also correlated with the development of RILT.Fifty three patients were evaluable for this study. Twenty one patients (39%) developed radiologic signs of RILT Grade >1 but only three of them (5.6%) developed clinical symptoms (Grade 2). We could not find any association between the different CCL18 concentrations and a higher incidence of RILT. Statistical significant factors were the planning target volume (odds ratio OR: 1.003, p = 0.010), the volume of the lung receiving > 20 Gy (OR: 1.132 p = 0.004) and age (OR: 0.917, p = 0.008). There was no association between serial CCL18 concentrations with tumor response and overall survival.In our study the dosimetric parameters remained the most potent predictors of RILT. Further studies are needed in order to estimate the role of CCL18 in the development of early RILT.
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Survival benefit of transarterial chemoembolization in patients with metastatic hepatocellular carcinoma: a single center experience. BMC Gastroenterol 2017; 17:98. [PMID: 28797231 PMCID: PMC5553671 DOI: 10.1186/s12876-017-0656-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 08/01/2017] [Indexed: 12/30/2022] Open
Abstract
Background As prognosis of patients with metastatic hepatocellular carcinoma (HCC) is mainly determined by intrahepatic HCC progression, local treatment with TACE may result in improved OS, although it is not recommended. The purpose of this study was to analyze retrospectively the efficacy of TACE and its impact on OS in patients with metastatic hepatocellular carcinoma (HCC). Methods Two hundred and fifteen patients with metastatic HCC who were treated at our Liver Center between 2003 and 2014 were included in this retrospective analysis. Medical records, laboratory parameters and imaging studies were analyzed. Treatment of metastatic HCC and OS were assessed Results One hundred and two patients (47.4%) did not receive any HCC specific treatment while 48 patients (22.3%) were treated with sorafenib, 42 patients (19.5%) with TACE and 23 patients (10.7%) received treatment with TACE and sorafenib in combination. Survival analyses and Cox regression models revealed that TACE and a combination therapy of TACE and sorafenib were significant prognostic factors in metastatic HCC. However, further analyses revealed that there was no additional prognostic effect of adding sorafenib to TACE treatment in this patient cohort. Conclusions In metastatic HCC, treatment of intrahepatic tumor by TACE may be associated with improved survival. These results support the prognostic importance of treating intrahepatic HCC even in patients with metastatic disease. Therefore, we suggest evaluating the technical feasibility of TACE in all metastatic patients. Electronic supplementary material The online version of this article (doi:10.1186/s12876-017-0656-z) contains supplementary material, which is available to authorized users.
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Excellent local control and tolerance profile after stereotactic body radiotherapy of advanced hepatocellular carcinoma. Radiat Oncol 2017; 12:116. [PMID: 28701219 PMCID: PMC5508695 DOI: 10.1186/s13014-017-0851-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Accepted: 07/04/2017] [Indexed: 12/19/2022] Open
Abstract
Background To evaluate the efficacy and toxicity of stereotactic body radiotherapy (SBRT) in the treatment of advanced hepatocellular carcinoma (HCC). Material and Methods Patients with large HCCs (median diameter 7 cm, IQR 5-10 cm) with a Child-Turcotte-Pugh (CTP) score A (60%) or B (40%) and Barcelona-Clinic Liver Cancer (BCLC) classification stage B or C were treated with 3 to 12 fractions to allow personalized treatment according to the size of the lesions and the proximity of the lesions to the organs at risk aiming to give high biologically equivalent doses assuming an α/β ratio of 10 Gy for HCC. Primary end points were in-field local control and toxicity assessment. Results Forty seven patients with 64 lesions were treated with SBRT (median 45 Gy in 3–12 fractions) with a median follow up for patients alive of 19 months. The median biological effective dose was 76 Gy (IQR 62–86 Gy). Tumor vascular thrombosis was present in 28% and an underlying liver disease in 87% (hepatitis B or C in 21%, alcohol related in 51%, nonalcoholic steatohepatitis in 13% of the patients, primary biliary cirrhosis 2%). Eighty three percent received prior and in most cases multiple therapies. Local control at 1 year was 77%. The median overall survival from the start of SBRT was 9 months (95% CI 7.7–10.3). Gastrointestinal toxicities grade ≥ 2 were observed in 3 (6.4%) patients. An increase in CTP score without disease progression was observed in 5 patients, of whom one patient developed a radiation induced liver disease. One patient died due to liver failure 4 months after treatment. Conclusion SBRT is an effective local ablative therapy which leads to high local control rates with moderate toxicity for selected patients with large tumors. Electronic supplementary material The online version of this article (doi:10.1186/s13014-017-0851-7) contains supplementary material, which is available to authorized users.
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Correlation of 18F-Fluorodeoxyglucose Positron Emission Tomography Parameters with Patterns of Disease Progression in Locally Advanced Pancreatic Cancer after Definitive Chemoradiotherapy. Clin Oncol (R Coll Radiol) 2017; 29:370-377. [PMID: 28190636 PMCID: PMC5429392 DOI: 10.1016/j.clon.2017.01.038] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 01/09/2017] [Accepted: 01/17/2017] [Indexed: 12/13/2022]
Abstract
AIMS A proportion of patients with pancreatic cancer never develop metastatic disease. We evaluated a role for 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) in identifying a subset of patients with locally advanced pancreatic cancer (LAPC) who never develop metastatic disease and only experience local disease and may therefore benefit from local treatment intensification. MATERIAL AND METHODS Patients with histologically confirmed LAPC entered a single-centre phase II study of definitive upfront chemoradiotherapy (CRT). All patients underwent FDG-PET/CT before and 6 weeks after CRT. Tumour volume, standardised uptake values (SUVmax, SUVpeak, SUVmean, SUVmedian) and total lesion glycolysis (TLG) were measured on each scan and the response in each parameter was evaluated. The presence or absence of metastatic disease was noted on contrast-enhanced CT carried out every 3 months for 1 year and then at clinician discretion. RESULTS Twenty-three patients with LAPC were recruited; 17/23 completed treatment and had interpretable sequential imaging. Twenty-four per cent of patients only ever experienced local disease. Median pre-CRT FDG-PET parameters were significantly lower in patients with local disease only during follow-up compared with those who developed metastatic disease: SUVmax 3.8 versus 8.6 (P=0.006), SUVpeak 2.5 versus 7.5 (P=0.002), SUVmean 1.8 versus 3.3 (P=0.001), SUVmedian 1.7 versus 3.0 (P=0.002), TLG 26.9 versus 115.9 (P=0.006). Tumour volume, post-CRT FDG-PET values and their relative change were not statistically different between local disease and metastatic disease groups. Receiver operating characteristic curves for pre-CRT FDG-PET parameters to predict those who never develop metastatic disease all had areas under the curve (AUCs) ≥ 0.932. Pre-CRT FDG-PET SUVmax < 6.2 predicted patients with local disease only during follow-up with 100.0% sensitivity and 92.3% specificity, 80.0% positive predictive value and 100% negative predictive value. CONCLUSIONS Our findings suggest that patients with less FDG-avid tumours are less likely to metastasise and may therefore benefit from upfront local treatment intensification.
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Pancreatic stellate cells in pancreatic cancer: In focus. Pancreatology 2017; 17:514-522. [PMID: 28601475 DOI: 10.1016/j.pan.2017.05.390] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 05/23/2017] [Accepted: 05/24/2017] [Indexed: 12/11/2022]
Abstract
Pancreatic stellate cells are stromal cells that have multiple physiological functions such as the production of extracellular matrix, stimulation of amylase secretion, phagocytosis and immunity. In pancreatic cancer, stellate cells exhibit a different myofibroblastic-like morphology with the expression of alpha-smooth muscle actin, the activated form is engaged in several mechanisms that support tumorigenesis and cancer invasion and progression. In contrast to the aforementioned observations, eliminating the stromal cells that are positive for alpha-smooth muscle actin resulted in immune-evasion of the cancer cells and resulted in worse prognosis in animal models. Understanding the cancer-stromal signaling in pancreatic adenocarcinoma will provide novel strategies for therapy. Here we provide an updated review of studies that handle the topic "pancreatic stellate cells in cancer" and recent experimental approaches that can be the base for future directions in therapy.
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Comparison of four target volume definitions for pancreatic cancer. Guidelines for treatment of the lymphatics and the primary tumor. Strahlenther Onkol 2013; 189:407-16. [PMID: 23553047 DOI: 10.1007/s00066-013-0332-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 02/13/2013] [Indexed: 01/06/2023]
Abstract
BACKGROUND AND PURPOSE Target volume definitions for radiotherapy in pancreatic ductal adenocarcinoma (PDAC) vary substantially. Some groups aim to treat the primary tumor only, whereas others include elective lymph nodes (eLNs). eLNs close to the primary tumor are often included unintentionally within the treatment volume, depending on the respective treatment philosophies. We aimed to measure the percentages of anatomical coverage of eLNs by comparing four different contouring guidelines. PATIENTS AND METHODS Planning target volumes (PTVs) were contoured using planning computed tomography (CT) scans of 11 patients with PDAC based on the Oxford, RTOG (Radiation Therapy Oncology Group), Michigan, and SCALOP (Selective Chemoradiation in Advanced Localised Pancreatic Cancer trial) guidelines. Clinical target volumes (CTVs) included the peripancreatic, para-aortic, paracaval, celiac trunk, superior mesenteric, and portal vein lymph node areas. Volumetric comparisons of the coverage of all eLN regions were conducted to illustrate the differences between the four contouring strategies. RESULTS The PTV sizes of the RTOG and Oxford guidelines were comparable. The SCALOP and Michigan PTV sizes were similar to each other and significantly smaller than the RTOG and Oxford PTVs. A large variability of eLN coverage was found for the various subregions according to the respective contouring strategies. CONCLUSION This is the first study to directly compare the percentage of anatomical coverage of eLNs according to four PTVs in the same patient cohort. Potential practical consequences are discussed in detail.
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Targeting ATR in vivo using the novel inhibitor VE-822 results in selective sensitization of pancreatic tumors to radiation. Cell Death Dis 2012; 3:e441. [PMID: 23222511 PMCID: PMC3542617 DOI: 10.1038/cddis.2012.181] [Citation(s) in RCA: 252] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 09/29/2012] [Accepted: 10/04/2012] [Indexed: 12/12/2022]
Abstract
Combined radiochemotherapy is the currently used therapy for locally advanced pancreatic ductal adenocarcinoma (PDAC), but normal tissue toxicity limits its application. Here we test the hypothesis that inhibition of ATR (ATM-Rad3-related) could increase the sensitivity of the cancer cells to radiation or chemotherapy without affecting normal cells. We tested VE-822, an ATR inhibitor, for in vitro and in vivo radiosensitization. Chk1 phosphorylation was used to indicate ATR activity, γH2AX and 53BP1 foci as evidence of DNA damage and Rad51 foci for homologous recombination activity. Sensitivity to radiation (XRT) and gemcitabine was measured with clonogenic assays in vitro and tumor growth delay in vivo. Murine intestinal damage was evaluated after abdominal XRT. VE-822 inhibited ATR in vitro and in vivo. VE-822 decreased maintenance of cell-cycle checkpoints, increased persistent DNA damage and decreased homologous recombination in irradiated cancer cells. VE-822 decreased survival of pancreatic cancer cells but not normal cells in response to XRT or gemcitabine. VE-822 markedly prolonged growth delay of pancreatic cancer xenografts after XRT and gemcitabine-based chemoradiation without augmenting normal cell or tissue toxicity. These findings support ATR inhibition as a promising new approach to improve the therapeutic ration of radiochemotherapy for patients with PDAC.
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Abstract
PURPOSE The inhibition of activated Ras combined with radiotherapy was identified as a potential method for radiosensitization. MATERIALS AND METHODS Immunoblotting was used to control for prenylation inhibition of the respective Ras isoforms and for changes in activity of downstream proteins. Clonogenic assays with human and rodent tumour cell lines and transfected cell lines served for the testing of radiosensitivity. Xenograft tumours were treated with farnesyl transferase inhibitors and radiation and assayed for ex vivo plating efficiency, regrowth of tumours and EF5 staining for detection of hypoxia. Concurrent treatment with L-778,123 and radiotherapy was performed in non-small cell lung cancer (NSCLC) and head and neck cancer (HNC) patients. RESULTS Blocking the prenylation of Ras proteins in cell lines with Ras activated by mutations or receptor signalling resulted in radiation sensitization in in vitro and in vivo. The PI3 kinase downstream pathway was identified as a contributor to Ras-mediated radiation resistance. Additionally, increased oxygenation of xenograft tumours was observed after FTI treatment. Combined treatment in a phase I study was safe and effective in NSCLC and HNC. CONCLUSIONS Tumour cells with activated Ras were sensitized to radiation. Unravelling the underlying mechanisms promises to lead to even more specific drugs with higher potency and safety.
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Abstract
Caveolin-1 (Cav-1) is an integral transmembrane protein and a critical component in interactions of integrin receptors with cytoskeleton-associated and signaling molecules. Since integrin-mediated cell adhesion generates signals conferring radiation resistance, we examined the effects of small interfering RNA-mediated knockdown of Cav-1 alone or in combination with beta1-integrin or focal adhesion kinase (FAK) on radiation survival and proliferation of pancreatic carcinoma cell lines. Irradiation induced Cav-1 expression in PATU8902, MiaPaCa2 and Panc1 cell lines. The cell lines showed significant radiosensitization after knockdown of Cav-1, beta1-integrin or FAK and cholesterol depletion by beta-cyclodextrin relative to nonspecific controls. Under knockdown conditions, proliferation of non-irradiated and irradiated cells was significantly attenuated relative to controls. These findings correlated with changes in expression or phosphorylation of Akt, glycogen synthase kinase 3beta, Paxillin, Src, c-Jun N-terminal kinase and mitogen-activated protein kinase. Analysis of DNA microarray data revealed a Cav-1 overexpression in a subset of pancreatic ductal adenocarcinoma samples. The data presented show, for the first time, that disruption of interactions of Cav-1 with beta1-integrin or FAK affects radiation survival and proliferation of pancreatic carcinoma cells and suggest that Cav-1 is critical to these processes. These results indicate that strategies targeting Cav-1 may be useful as an approach to improve conventional therapies, including radiotherapy, for pancreatic cancer.
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[The role of radiochemotherapy in multimodal therapy of pancreatic cancer]. Dtsch Med Wochenschr 2007; 132:808-12. [PMID: 17427091 DOI: 10.1055/s-2007-973625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Abstract
BACKGROUND Ductal pancreatic carcinoma ranks third among malignancies of the gastrointestinal tract and its incidence is rising. Today, patients with this disease still have fatal prognosis necessitating efforts towards more effective treatment. MATERIAL AND METHODS This report provides a review of adjuvant and neoadjuvant radiotherapy in pancreatic carcinoma without distant metastasis. Particular respect is given to prospective, randomized trials. They are analyzed according to clinical staging: 1. In resectable tumors adjuvant, neoadjuvant or intraoperative radiotherapy is performed. 2. Radiotherapy in neoadjuvant intention is an approach for downstaging to achieve resectability in initially irresectable tumors. RESULTS The widespread use of new techniques such as supervoltage irradiation, computer based 3-D-planning, interventional therapy and combination of different therapeutic modalities induced a great number of studies. When concomitant chemotherapy was added to radiotherapy, results became significantly better compared to exclusive radiotherapy. It is shown that patients with operable tumors will have better survival rates and lower risk of relapse, if radiochemotherapy is added to surgery. Patients with irresectable tumors possible can be downstaged and be brought to resection nevertheless. CONCLUSIONS Simultaneous radiochemotherapy with 5-FU and mitomycin C can be performed without elevated risk of acute side effects of higher degree. This approach may be indicated in the case of adjuvant situations in patients free of distant metastases. Neoadjuvant simultaneous radiochemotherapy should only be performed as a part of a clinical trial.
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MESH Headings
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Carcinoma, Intraductal, Noninfiltrating/drug therapy
- Carcinoma, Intraductal, Noninfiltrating/mortality
- Carcinoma, Intraductal, Noninfiltrating/radiotherapy
- Carcinoma, Intraductal, Noninfiltrating/surgery
- Chemotherapy, Adjuvant
- Clinical Trials as Topic
- Combined Modality Therapy
- Humans
- Neoplasm Staging
- Pancreatic Neoplasms/drug therapy
- Pancreatic Neoplasms/mortality
- Pancreatic Neoplasms/radiotherapy
- Pancreatic Neoplasms/surgery
- Radiotherapy Planning, Computer-Assisted
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