Extracranial oligometastases: a subset of metastases curable with stereotactic radiotherapy

Machine learning predicts conventional imaging metastasis-free survival (MFS) for oligometastatic castration-sensitive prostate cancer (omCSPC) using prostate-specific membrane antigen (PSMA) PET radiomics

PURPOSE

This study investigated imaging biomarkers derived from PSMA-PET acquired pre- and post-metastasis-directed therapy (MDT) to predict 2-year metastasis-free survival (MFS), which provides valuable early response assessment to improve patient outcomes.

MATERIALS/METHODS

An international cohort of 117 oligometastatic castration-sensitive prostate cancer (omCSPC) patients, comprising 34 from John Hopkins Hospital (JHH) and 83 from Baskent University (BU), were treated with stereotactic ablative radiation therapy (SABR) MDT with both pre- and post-MDT PSMA-PET/CT scans acquired. PET radiomic features were analyzed from a CT-PET fusion defined gross tumor volume ((GTV) or zone 1), and a 5 mm expansion ring area outside the GTV (zone 2). A total of 1748 PET radiomic features were extracted from these zones. The six most significant features selected using the Chi2 method, along with five clinical parameters (age, Gleason score, number of total lesions, untreated lesions, and pre-MDT prostate-specific antigen (PSA)) were extracted as inputs to the models. Various machine learning models, including Random Forest, Decision Tree, Support Vector Machine, and Naïve Bayesian, were employed for 2-year MFS prediction and tested using leave-one-out and cross-institution validation.

RESULTS

Six radiomic features, including Total Energy, Entropy, and Standard Deviation from pre-PSMA-PET zone 1, Total Energy and Contrast from post-PSMA-PET zone 1, and Entropy from pre-PSMA-PET zone 2, along with five clinical parameters were selected for predicting 2-year MFS. In a leave-one-out test with all the patients, random forest achieved an accuracy of 80 % and an AUC of 0.82 in predicting 2-year MFS. In cross-institution validation, the model correctly predicted 2-year MFS events with an accuracy of 75 % and an AUC of 0.77 for patients from JHH, and an accuracy of 78 % and an AUC of 0.80 for BU patients, respectively.

CONCLUSION

Our study demonstrated the promise of using pre- and post-MDT PSMA-PET-based imaging biomarkers for MFS prediction for omCSPC patients.

Beyond success: unveiling the hidden potential of radiotherapy and immunotherapy in solid tumors

Immunotherapy, particularly with immune checkpoint inhibitors, has significantly transformed cancer treatment. Despite its success, many patients struggle to respond adequately or sustain long-lasting clinical improvement. A growing consensus has emerged that radiotherapy (RT) enhances the response rate and overall efficacy of immunotherapy. Although combining RT and immunotherapy has been extensively investigated in preclinical models and has shown promising results, establishing itself as a dynamic and thriving area of research, clinical evidence for this combination strategy over the past five years has shown both positive and disappointing results, suggesting the need for a more nuanced understanding. This review provides a balanced and updated analysis of the combination of immunotherapy and RT. We summarized the preclinical mechanisms through which RT boosts antitumor immune responses and mainly focused on the outcomes of recently updated clinical trials, including those that may not have met expectations. We investigated the optimization of the therapeutic potential of this combined strategy, including key challenges, such as fractionation and scheduling, lymph node irradiation, and toxicity. Finally, we offered insights into the prospects and challenges associated with the clinical translation of this combination therapy, providing a realistic perspective on the current state of research and potential future directions.

Enhancement of Radiation Sensitivity by Cathepsin L Suppression in Colon Carcinoma Cells

Cancer is one of the main causes of death globally. Radiotherapy/Radiation therapy (RT) is one of the most common and effective cancer treatments. RT utilizes high-energy radiation to damage the DNA of cancer cells, leading to their death or impairing their proliferation. However, radiation resistance remains a significant challenge in cancer treatment, limiting its efficacy. Emerging evidence suggests that cathepsin L (cath L) contributes to radiation resistance through multiple mechanisms. In this study, we investigated the role of cath L, a member of the cysteine cathepsins (caths) in radiation sensitivity, and the potential reduction in radiation resistance by using the specific cath L inhibitor (Z-FY(tBu)DMK) or by knocking out cath L with CRISPR/Cas9 in colon carcinoma cells (caco-2). Cells were treated with different doses of radiation (2, 4, 6, 8, and 10), dose rate 3 Gy/min. In addition, the study conducted protein expression analysis by western blot and immunofluorescence assay, cytotoxicity MTT, and apoptosis assays. The results demonstrated that cath L was upregulated in response to radiation treatment, compared to non-irradiated cells. In addition, inhibiting or knocking out cath L led to increased radiosensitivity in contrast to the negative control group. This may indicate a reduced ability of cancer cells to recover from radiation-induced DNA damage, resulting in enhanced cell death. These findings highlight the possibility of targeting cath L as a therapeutic strategy to enhance the effectiveness of RT. Further studies are needed to elucidate the underlying molecular mechanisms and to assess the translational implications of cath L knockout in clinical settings. Ultimately, these findings may contribute to the development of novel treatment approaches for improving outcomes of RT in cancer patients.

Automated detection, delineation and quantification of whole-body bone metastasis using FDG-PET/CT images

Non-small cell lung cancer (NSCLC) patients with the metastatic spread of disease to the bone have high morbidity and mortality. Stereotactic ablative body radiotherapy increases the progression free survival and overall survival of these patients with oligometastases. FDG-PET/CT, a functional imaging technique combining positron emission tomography (PET) with 18 F-fluorodeoxyglucose (FDG) and computer tomography (CT) provides improved staging and identification of treatment response. It is also associated with reduction in size of the radiotherapy tumour volume delineation compared with CT based contouring in radiotherapy, thus allowing for dose escalation to the target volume with lower doses to the surrounding organs at risk. FDG-PET/CT is increasingly being used for the clinical management of NSCLC patients undergoing radiotherapy and has shown high sensitivity and specificity for the detection of bone metastases in these patients. Here, we present a software tool for detection, delineation and quantification of bone metastases using FDG-PET/CT images. The tool extracts standardised uptake values (SUV) from FDG-PET images for auto-segmentation of bone lesions and calculates volume of each lesion and associated mean and maximum SUV. The tool also allows automatic statistical validation of the auto-segmented bone lesions against the manual contours of a radiation oncologist. A retrospective review of FDG-PET/CT scans of more than 30 candidate NSCLC patients was performed and nine patients with one or more metastatic bone lesions were selected for the present study. The SUV threshold prediction model was designed by splitting the cohort of patients into a subset of 'development' and 'validation' cohorts. The development cohort yielded an optimum SUV threshold of 3.0 for automatic detection of bone metastases using FDG-PET/CT images. The validity of the derived optimum SUV threshold on the validation cohort demonstrated that auto-segmented and manually contoured bone lesions showed strong concordance for volume of bone lesion (r = 0.993) and number of detected lesions (r = 0.996). The tool has various applications in radiotherapy, including but not limited to studies determining optimum SUV threshold for accurate and standardised delineation of bone lesions and in scientific studies utilising large patient populations for instance for investigation of the number of metastatic lesions that can be treated safety with an ablative dose of radiotherapy without exceeding the normal tissue toxicity.

Radiation therapy-induced left vocal cord paralysis following lung stereotactic body radiation therapy: A case report and review of the literature

We report the case of a 50-year old women with an oncological history of metastatic breast carcinoma who underwent lung stereotactic body radiation therapy (SBRT) of 60Gy in 8 fractions for a left upper lobe metastatic lesion. Seven months later, she complains about hoarseness and weakness of voice. Tumoral relapse and other frequent etiologies were excluded. The diagnosis of radiation induced left recurrent laryngeal nerve paralysis causing left vocal cord paralysis (VCP) was made. The symptomatology did not improve till the disease progression and death of the patient 29 months after SBRT. VCP after lung SBRT is a rare adverse event that has not yet been well described in the medical literature.

Ways to improve breast cancer patients' management and clinical outcome: The 2020 Assisi Think Tank Meeting

We report on the third Assisi Think Tank Meeting (ATTM) on breast cancer, a brainstorming project which involved European radiation and clinical oncologists who were dedicated to breast cancer research and treatment. Held on February 2020, the ATTM aimed at identifying key clinical questions in current clinical practice and "grey" areas requiring research to improve management and outcomes. Before the meeting, three key topics were selected: 1) managing patients with frailty due to either age and/or multi-morbidity; 2) stereotactic radiation therapy and systemic therapy in the management of oligometastatic disease; 3) contralateral breast tumour prevention in BCRA-mutated patients. Clinical practice in these areas was investigated by means of an online questionnaire. In the lapse period between the survey and the meeting, the working groups reviewed data, on-going studies and the clinical challenges which were then discussed in-depth and subjected to intense brainstorming during the meeting; research protocols were also proposed. Methodology, outcome of discussions, conclusions and study proposals are summarized in the present paper. In conclusion, this report presents an in-depth analysis of the state of the art, grey areas and controversies in breast cancer radiation therapy and discusses how to confront them in the absence of evidence-based data to guide clinical decision-making.

GOECP/SEOR radiotheraphy guidelines for non-small-cell lung cancer

Non-small cell lung cancer (NSCLC) is a heterogeneous disease accounting for approximately 85% of all lung cancers. Only 17% of patients are diagnosed at an early stage. Treatment is multidisciplinary and radiotherapy plays a key role in all stages of the disease. More than 50% of patients with NSCLC are treated with radiotherapy (curative-intent or palliative). Technological advances-including highly conformal radiotherapy techniques, new immobilization and respiratory control systems, and precision image verification systems-allow clinicians to individualize treatment to maximize tumor control while minimizing treatment-related toxicity. Novel therapeutic regimens such as moderate hypofractionation and advanced techniques such as stereotactic body radiotherapy (SBRT) have reduced the number of radiotherapy sessions. The integration of SBRT into routine clinical practice has radically altered treatment of early-stage disease. SBRT also plays an increasingly important role in oligometastatic disease. The aim of the present guidelines is to review the role of radiotherapy in the treatment of localized, locally-advanced, and metastatic NSCLC. We review the main radiotherapy techniques and clarify the role of radiotherapy in routine clinical practice. These guidelines are based on the best available evidence. The level and grade of evidence supporting each recommendation is provided.

Development of a Prognostic Model for Overall Survival in Patients with Extracranial Oligometastatic Disease Treated with Stereotactic Body Radiation Therapy

BACKGROUND

Patients with oligometastatic disease (OMD) may experience durable disease control with ablative therapy to all sites of disease. Stereotactic body radiation therapy (SBRT) is an important modality in the management of OMD patients though a validated prognostic model for OMD patients treated with SBRT is currently lacking. The purpose of this study was to develop a prognostic model for overall survival (OS) in OMD patients treated with SBRT.

METHODS

A multi-institutional database of extracranial OMD patients treated with SBRT was used for model development. The final prognostic model was generated in a training set using recursive partitioning analysis representing 75% of the population. Model performance was evaluated in the reserved test set.

RESULTS

1,033 patients were included in the analysis. The median OS for the entire cohort was 44.2 months (95% confidence interval: 39.2-48.8 months). The variables used in the regression tree, in order of importance, were primary histology, lung-only OMD on presentation, the timing of OMD presentation and age at the start of SBRT. A full 5-category risk stratification system based on the terminal nodes possessed fair to good discriminative power with a Harrell's concordance statistic of 0.683 (0.634-0.731) and time-dependent area under the receiver operating characteristic curve of 0.709 (0706-0.711) in the test set, with good calibration. A simplified risk stratification system consisting of 3 risk categories was also proposed for greater ease-of-use with comparable performance.

CONCLUSION

A clinical prognostic model for OS in patients with extracranial OMD treated with SBRT has been developed and validated.

A priori quality assurance using a benchmark case of the randomized phase 2 GORTEC 2014-14 in oligometastatic head and neck cancer patients

PURPOSE

A Benchmark Case (BC) was performed as part of the quality assurance process of the randomized phase 2 GORTEC 2014-14 OMET study, testing the possibility of multisite stereotactic radiation therapy (SBRT) alone in oligometastatic head and neck squamous cell carcinoma (HNSCC) as an alternative to systemic treatment and SBRT.

MATERIAL AND METHODS

Compliance of the investigating centers with the prescription, delineation, planning and evaluation recommendations available in the research protocol was assessed. In addition, classical dosimetric analysis was supplemented by quantitative geometric analysis using conformation indices.

RESULTS

Twenty centers participated in the BC analysis. Among them, four major deviations (MaD) were reported in two centers. Two (10%) centers in MaD had omitted the satellite tumor nodule and secondarily validated after revision. Their respective DICE indexes were 0.37 and 0 and use of extracranial SBRT devices suboptimal There were significant residual heterogeneities between participating centers, including those with a similar SBRT equipment, with impact of plan quality using standard indicators and geometric indices.

CONCLUSION

A priori QA using a BC conditioning the participation of the clinical investigation centers showed deviations from good SBRT practice and led to the exclusion of one out of the twenty participating centers. The majority of centers have demonstrated rigorous compliance with the research protocol. The use of quality indexes adds a complementary approach to improve assessment of plan quality.

Increasing Demand on Human Capital and Resource Utilization in Radiation Therapy: The Past Decade

PURPOSE

To quantify the change resource utilization in radiation therapy in the context of advancing technologies and techniques over the last decade.

METHODS AND MATERIALS

Prospectively, the time to complete radiation therapy workflow tasks was captured between January 1, 2020, and December 31, 2020. The institutional task workflows are specific to each technique and broadly organized into 4 categories: 3-dimenstional conformal radiation therapy, intensity modulated radiation therapy, volumetric modulated arc therapy simple, and volumetric modulated arc therapy complex. These discipline-specific task times were used to quantify a resource utilization factor, which is the median time taken to complete all tasks for each category divided by the median time for 3-dimensional conformal radiation therapy treatments. Retrospectively, all plans treated between January 1, 2012, and December 31, 2019, were quantified and categorized. The resource factor was applied to determine resource utilization. For context, institutional staffing levels were captured across the same decade for medical dosimetrists, medical physicists, and radiation oncologists.

RESULTS

This analysis includes 30,229 patient plans in the retrospective data set and 4747 patient plans in the prospective data set. This analysis demonstrates that over this period, patient numbers increased by approximately 45%, whereas time-based human resources increased by almost 150%. The resource allocation factors for 3-dimenstional conformal radiation therapy, intensity modulated radiation therapy, volumetric modulated arc therapy simple, and volumetric arc therapy complex were 1.0, 2.4, 2.9, and 4.3, respectively. Across the 3 disciplines, staffing levels increased from 15 to 17 (13%) for medical dosimetrists, from 10 to 13 (30%) for medical physicists, and from 16 to 23 (44%) for radiation oncologists.

CONCLUSIONS

This work demonstrates the increase in resource utilization due to the introduction of advanced technologies and changes in radiation therapy techniques over the past decade. Human resource utilization is the predominant factor and should be considered with increasing patient volume for operational planning.

Defining oligometastatic non-small cell lung cancer: concept versus biology, a literature review

Objective

In this review, the concept of (synchronous) oligometastatic disease in patients with non-oncogene-driven non-small cell lung cancer (NSCLC) will be placed in the context of tumor biology and metastatic growth patterns. We will also provide considerations for clinical practice and future perspectives, which will ultimately lead to better patient selection and oligometastatic disease outcome.

Background

The treatment landscape of metastasized NSCLC has moved from "one-size fits all" to a personalized approach. Prognosis has traditionally been poor but new treatment options, such as immunotherapy and targeted therapy, brighten future perspectives. Another emerging development is the recognition of patients with so-called "oligometastatic" state of disease. Oligometastatic disease has been recognized as a distinct clinical presentation in which the tumor is stated to be early in its evolution of metastatic potential. It is suggested that this stage of disease has an indolent course, comes with a better prognosis and therefore could be considered for radical multimodality treatment.

Methods

Narrative overview of the literature synthesizing the findings of literature retrieved from searches of computerized databases, hand searches, and authoritative texts.

Conclusions

Oligometastatic NSCLC is a broad spectrum disease, with a variable prognosis. Although the biology and behavior of "intermediate state" of metastatic disease are not fully understood, there is evidence that a subgroup of patients can benefit from local radical treatment when integrated into a multimodality regime. The consensus definition of oligometastatic NSCLC, including accurate staging, may help to uniform future trials. The preferable treatment strategy seems to sequential systemic treatment with subsequent local radical treatment in patients with a partial response or stable disease. Prognostic factors such as N-stage, number and site of distant metastases, tumor volume, performance status, age, and tumor type should be considered. The local radical treatment strategy has to be discussed in a multidisciplinary team meeting, taking into account patient characteristics and invasiveness of the procedure. However, many aspects remain to be explored and learned about the cancer biology and characteristics of intermediate state tumors.

Narrative review: molecular and genetic profiling of oligometastatic non-small cell lung cancer

Objective

The objectives of this review are to discuss: the definition, clinical and biologic features of oligometastatic non-small cell lung cancer (NSCLC), as well as the concept of treating oligoprogression in oligometastatic NSCLC.

Background

A substantial proportion of patients diagnosed with lung cancer present with metastatic disease, and a large portion of patients who present with localized disease later develop metastases. Oligometastatic NSCLC is defined as an intermediate state between localized and widespread metastatic disease, where there may be a role for curative localized therapy approach by treating the primary tumor and all metastases with radiotherapy or surgery. Despite the increasing application of this approach in patients with lung cancer, the identification of patients who might benefit from this approach is yet to be well characterized.

Methods

After a systematic review of the literature, a PubMed search was performed using the English language and the key terms: oligometastatic, non-small cell lung cancer (NSCLC), localized consolidative treatment (LCT), biomarkers, biologic features, clinical features. Over 500 articles were retrieved between 1889–2021. A total of 178 papers discussing the definition, clinical and biologic factors leading to oligometastatic NSCLC were reviewed and included in the discussion of this paper.

Conclusions

Oligometastatic NSCLC is a unique entity. Identifying patients who have oligometastatic NSCLC accurately using a combination of clinical and biologic features and treating them with localized consolidative approach appropriately results in improvement of outcome. Further understanding of the molecular mechanisms driving the formation of oligometastatic NSCLC is an important area of focus for future studies.

Oligometastatic Lung Cancer Defined by Biology, Science, and Secondary Growths

Breast cancer was the first malignant tumor for which TNM classification was proposed by the International Union Against Cancer. Volume and distribution of tumor burden were considered clinically important in this cancer. Lung cancer is caused by excessive cigarette smoking. Prognosis is worst in small cell lung cancer and in non-small cell lung cancer measuring over 3 cm in size and having regional lymphatic spread. Metastatic spread from lung cancer is favored by lymphatic spread to the locoregional lymph nodes and blood-borne spread to 5 sites-lung, brain, bone, liver, and adrenal-all of which are unfavorable prognostic indicators.

Stereotactic Body Radiotherapy for Lymph Node Oligometastases: Real-World Evidence From 90 Consecutive Patients

AIMS

To evaluate the efficacy and toxicity of extracranial stereotactic body radiotherapy (SBRT) in the treatment of oligometastatic lymph node involvement in the mediastinum, retroperitoneum, or pelvis, in a consecutive group of patients from real clinical practice outside clinical trials.

METHODS

A retrospective analysis of 90 patients with a maximum of four oligometastases and various primary tumors (the most common being colorectal cancers). The endpoints were local control of treated metastases (LC), freedom from widespread dissemination (FFWD), progression-free survival (PFS), overall survival (OS), and freedom from systemic treatment (FFST). Acute and delayed toxicities were also evaluated.

RESULTS

The median follow-up after SBRT was 34.9 months. The LC rate at three and five years was 68.4 and 56.3%, respectively. The observed median FFWD was 14.6 months, with a five-year FFWD rate of 33.7%. The median PFS was 9.4 months; the three-year PFS rate was 19.8%. The median FFST was 14.0 months; the five-year FFST rate was 23.5%. The OS rate at three and five years was 61.8 and 39.3%, respectively. Median OS was 53.1 months. The initial dissemination significantly shortened the time to relapse, death, or activation of systemic treatment-LC (HR 4.8, p < 0.001), FFWD (HR 2.8, p = 0.001), PFS (HR 2.1, p = 0.011), FFST (HR 2.4, p = 0.005), OS (HR 2.2, p = 0.034). Patients classified as having radioresistant tumors noticed significantly higher risk in terms of LC (HR 13.8, p = 0.010), FFWD (HR 3.1, p = 0.006), PFS (HR 3.5, p < 0.001), FFST (HR 3.2, p = 0.003). The multivariable analysis detected statistically significantly worse survival outcomes for initially disseminated patients as well as separately in groups divided according to radiosensitivity. No grade III or IV toxicity was reported.

CONCLUSION

Our study shows that targeted SBRT is a very effective and low toxic treatment for oligometastatic lymph node involvement. It can delay the indication of cytotoxic chemotherapy and thus improve and maintain patient quality of life. The aim of further studies should focus on identifying patients who benefit most from SBRT, as well as the correct timing and dosage of SBRT in treatment strategy.

Metastasis-directed stereotactic body radiation therapy in the management of oligometastatic head and neck cancer

INTRODUCTION

Recently major efforts have been made to define the oligometastatic setting, but for head and neck cancer (HNC) limited data are available. We aimed to evaluate outcome of oligometastatic HNC treated with Stereotactic body radiotherapy (SBRT) as metastasis-directed therapy.

MATERIALS AND METHODS

We analyzed patients treated with SBRT on a maximum of five oligometastases from HNC, in up to two organs. Concomitant treatment was allowed. End points were toxicity, local control of treated metastases (LC), progression-free survival (PFS) and overall survival (OS).

RESULTS

48 consecutive patients and 71 lesions were treated. With a follow-up of 20.2 months, most common primary tumors were larynx (29.2%) and salivary glands (29.2%), while common site of metastases was lung (59.1%). Median dose was 48 Gy (21-75) in 3-8 fractions. Treatment was well tolerated, with two patients reporting mild pain and nausea. LC rates at 1 and 2 years were 83.1% and 70.2%. Previous local therapy (HR 4.97; p = 0.002), oligoprogression (HR 4.07; p = 0.031) and untreated metastases (HR 4.19; p = 0.027) were associated with worse LC. PFS at 1 and 2 years were 42.2% and 20.0%. Increasing age (HR 1.03; p = 0.010), non-adenoid cystic carcinoma (HR 2.57; p = 0.034) and non-lung metastases (HR 2.20; p = 0.025) were associated with worse PFS. One- and 2-years OS were 81.0% and 67.1%. Worse performance status (HR 2.91; p = 0.049), non-salivary primary (HR 19.9; p = 0.005), non-lung metastases (HR 2.96; p = 0.040) were correlated with inferior OS.

CONCLUSIONS

SBRT can be considered a safe metastasis-directed therapy in oligometastatic HNC. Efficacy of the treatment seems to be higher when administered upfront in the management of metastatic disease; however, selection of patients need to be improved due to the relevant risk of appearance of new metastatic site after SBRT.

Volumetric and dosimetric impact of MRI in delineation of gross tumor volume of non-spinal vertebral metastases treated with stereotactic ablative radiation therapy

PURPOSE

To investigate the Gross Tumor Volumes (GTV) and its dosimetric impact of magnetic resonance imaging (MRI) assisted contouring for non-spinal metastasis treated with stereotactic ablative body radiotherapy (SABR).

MATERIAL AND METHODS

Five observer contours on CT (GTV_CT) and CT+MR (GTV_CT+MR) were evaluated against expert team contours (GTV_EC) for 14 selected cases. Dice Similarity Index (DSC) and Geographical Miss Index (GMI) quantify observer variation. We also analyze the maximum dose (D_max) and dose received by 0.35cc (D_0.35cc) of the spinal cord (SC) for GTV_CT and GTV_CT+MR, where optimization parameters and priorities were unchanged. Percent rank function is also evaluated for SC doses.

RESULTS

The mean DSC and GMI scores for the CT-only dataset are 0.6974 and 0.2851 and for CT+MR dataset is 0.7764 and 0.1907 respectively. Statistically, significant results were found for mean GTV volumes between GTV_EC versus GTV_CT and GTV_CT versus GTV_CT+MR (P<0.001). Dosimetric analysis of D_max and D_0.35cc exceeded 84.2% and 88.5% of times its respective threshold doses for CT-only dataset, whereas for the CT+MR dataset, it exceeded only by 18% and 15.7% times. 'Percent rank' function analysis for SC doses also indicates the same.

CONCLUSION

This study supports MRI fusion for GTV and OAR delineation for non-spinal metastasis. Our study showed that the dosimetric analysis is vital for observer variation studies and the addition of the MR data set is significant to improve the confidence of Stereotactic treatments.

Toxicity of L19-Interleukin 2 Combined with Stereotactic Body Radiation Therapy: A Phase 1 Study

PURPOSE

The immunocytokine L19-IL2 delivers interleukin-2 to the tumor by exploiting the selective L19-dependent binding of extradomain B of fibronectin on tumor blood vessels. In preclinical models, L19-IL2 has been shown to enhance the local and abscopal effects of radiation therapy. The clinical safety of L19-IL2 monotherapy has been established previously. In this study, the safety and tolerability of L19-IL2 after stereotactic body radiation therapy (SBRT) was assessed.

METHODS AND MATERIALS

Patients with oligometastatic solid tumors received radical SBRT to all visible metastases. Within 1 week after SBRT, intravenous L19-IL2 using a 3 + 3 dose escalation design was administered. Safety and tolerability were analyzed as the primary endpoint using the Common Terminology Criteria for Adverse Events 4.03 scoring system, with progression-free and overall survival as secondary endpoints.

RESULTS

A total of 6 patients in 2 L19-IL2 dose levels were included. The 15 million International Units (Mio IU) dose level was well tolerated with no dose-limiting toxicity. The most frequently reported adverse events were chills, noninfectious fever, fatigue, edema, erythema, pruritus, nausea/vomiting, and cough and dyspnea. Blood analysis revealed abnormalities in liver function tests, anemia, hypoalbuminemia, and hypokalemia. At the second dose level (ie, 22.5 Mio IU), which is the recommended dose for L19-IL2 monotherapy, all 3 included patients experienced dose-limiting toxicity but recovered without sequelae. We documented 2 long-term progression-free responders, both having non-small cell lung cancer as primary tumor.

CONCLUSIONS

Based on the results of this phase 1 clinical trial, the recommended phase 2 dose for SBRT combined with L19-IL2 is 15 Mio IU. The therapeutic efficacy of this combination is currently being evaluated in the multicentric EU-funded phase 2 clinical trial, ImmunoSABR.

Triple Discordances in Receptor Status During Breast Cancer Local Progression and Metastases: Case Report and Literature Review

Breast cancer is the most common female malignant neoplasm in Poland and around the world. Precise determination of tumor molecular profile allows application of appropriate anticancer therapy, increasing the chances of recovery. A 28-year-old woman detected a thickening in her left breast. Mammography showed a change measuring 60 mm (radiologically BIRADS 5). The biopsy revealed invasive ductal carcinoma, luminal subtype B, HER2 positive (cT3N1M0). Neoadjuvant chemotherapy was administered and then breast conserving surgery was performed. In postoperative histopathology cancer, biological subtype was evaluated: HER2 positive, nonluminal (ypT2ypN0cM0). Then, postoperative radiotherapy was performed. After 14 months, breast ultrasonography (US) and mammography (MGF) revealed the presence of suspicious changes (BIRADS 4). Tru-cut biopsy confirmed cancer recurrence (luminal subtype B, HER2 negative, ER negative, PgR: 10%, Ki-67: 70%). Despite implemented and modified chemotherapy regimens, local progression occurred. Genetic testing excluded BRCA gene mutation. The patient qualified for radical mastectomy modo Halsted (ypT4bN0cM0). Postoperative microscopic examination revealed triple negative breast invasive carcinoma of no special type. After 22 months, metastatic lesions in lungs and left retrosternal nodes appeared. Due to the limited possibilities of systemic treatment, the patient qualified for stereotactic radiotherapy of tumors in the lungs' and left retrosternal nodes. Advancement, histological type and molecular profile should be controlled at each stage of the disease, as they may change several times and require modification of therapy.

Phase II trial of high dose stereotactic body radiation therapy for lymph node oligometastases

Lymph nodes are common sites of oligometastases for several primaries. Stereotactic body radiation therapy (SBRT) represents an effective treatment but no consensus exists regarding dose and fractionation. Aim of this trial was to evaluate safety and efficacy of high-dose SBRT. We included patients with 1 to 3 lymph node metastases. Primary end-point was safety, while secondary end-points were in-field local control (LC), out-field lymph nodal progression free survival (LPFS), distant metastasis free survival (DMFS), progression free survival (PFS) and overall survival (OS). 64 lesions in 52 patients were treated from 2015 to 2019. Most common primary tumor was genitourinary cancer (75%), in particular prostate cancer (65.4%). With a median follow-up of 24.4 months (range 3-49), treatment was very well tolerated, with only 4 (7.7%) patients reporting acute side effects, all classified as grade 1, in the form of pain, fatigue, nocturia and dysuria. No toxicity ≥ grade 2 were reported. Rates of LC at 1, 2 and 3 years were 97.9%, 82.1% and 82.1%. Male sex (HR 0.12, p value 0.014) was associated with improved LC. LPFS at 1, 2 and 3 years were 69.6%, 49.6% and 46.1%, respectively, and DMFS was 81.74%, 67.5% and 58.5%, respectively. Presence of lesions in other organs was correlated with inferior DMFS (HR 3.82, p = 0.042). PFS at 1, 2 and 3 years were 67.4%, 42.4% and 31.86%, respectively. OS at 1, 2 and 3 years were 97.3%, 94.2%, 84%, respectively and significantly correlated with in-field recurrence (HR 8.72, p = 0.000). Our prospective trial confirms safety and efficacy of SBRT in the management of lymph node metastases. Registered Clinical trial NCT02570399.

GOECP/SEOR clinical recommendations for lung cancer radiotherapy during the COVID-19 pandemic

The coronavirus disease 2019 crisis has had a major and highly complex impact on the clinical practice of radiation oncology worldwide. Spain is one of the countries hardest hit by the virus, with devastating consequences. There is an urgent need to share experiences and offer guidance on decision-making with regard to the indications and standards for radiation therapy in the treatment of lung cancer. In the present article, the Oncological Group for the Study of Lung Cancer of the Spanish Society of Radiation Oncology reviews the literature and establishes a series of consensus-based recommendations for the treatment of patients with lung cancer in different clinical scenarios during the present pandemic.

[Treatment for Brain Metastases from EGFR Mutations NSCLC Patients: How Should We Choose in Clinical Practice?]

Brain metastasis of epidermal growth factor receptor (EGFR) sensitive mutations is a hot and difficult point in targeted era of non-small cell lung cancer (NSCLC) treatment, meanwhile it is also the central issue of controversy in the field of lung cancer treatment. Different results of different studies and different understanding of different disciplines, this field of treatment has been accompanied by different voices, patients without clinical symptoms can use targeted therapy first, and then start local radiotherapy with clinical symptoms or disease progression. It is a major model of the medical oncology. That is to say, taking symptoms and progress as indication and standard of local treatment intervention. In the absence of symptoms, local radiotherapy may increase patients' pain, which belongs to overtreatment. However, the perspective of radiotherapy is that brain metastases need to be treated clinically as early as possible, if not, it may affect the survival of patients. Early treatment of local lesions and increasing the depth of treatment are helpful to prolong the survival time of patients. This article refers to relevant literatures and summarizes the discussion from the perspective of pursuing the truth of disease treatment and problem solving in order to provide reference for patients' clinical practice.

Clinical features and prognostic factors for extracranial oligometastatic breast cancer in China

Evidence of an oligometastatic state in metastatic breast cancer (MBC) is relatively limited. The aim of our study was to investigate the clinical features and prognostic factors for extracranial oligometastatic breast cancer and to identify the best treatment approaches in this select population. Fifty postoperative inpatients diagnosed with extracranial oligometastatic breast cancer at the National Cancer Center in China between 2009 and 2014 were consecutively enrolled. Oligometastatic breast cancer was defined as MBC with three or fewer metastatic lesions confined to one organ; de novo Stage IV disease and local-regional recurrence were excluded. The median progression-free survival (PFS) and overall survival (OS) times were 15.2 and 78.9 months, respectively, and the 2-year PFS and 5-year OS rates were 40% and 58%, respectively. First-line treatment approach with standard systemic treatment + surgical resection for all metastatic lesions was an independent prognostic factor for prolonged PFS (hazard ratio = 0.32; 95% confidence interval [CI], 0.14-0.73; P = .006) and OS (hazard ratio = 0.35; 95% CI, 0.14-0.86; P = .022). Subgroup analysis showed that patients with a disease-free interval (DFI) ≥24 months, one metastatic lesion or the hormone receptor (HR) + subtype were more likely to get benefit from resection. Patients with oligometastatic breast cancer have a relatively good prognosis. Surgical resection for metastatic lesions could significantly improve PFS and OS. Further prospective research is warranted to confirm the results and to develop biomarkers for better patient selection.

Intensity-modulated radiation therapy administered to a previously irradiated spine is effective and well-tolerated

PURPOSE

This study sought to discern the clinical outcomes of intensity-modulated radiation therapy (IMRT) administered to the spine in patients who had undergone previous radiotherapy.

METHODS

A total of 81 sites of 74 patients who underwent previous radiotherapy administered to the spine or peri-spine and subsequently received IMRT for the spine were analyzed in this study. The prescribed dose of 80 Gy in a biologically effective dose (BED) of α/β = 10 (BED₁₀) was set as the planning target volume. The constraint for the spinal cord and cauda equine was D_0.1 cc ≤ 100 Gy and ≤ 150 Gy of BED for re-irradiation alone and the total irradiation dose, respectively.

RESULTS

The median follow-up period was 10.1 (0.9-92.1) months after re-irradiation, while the median interval from the last day of the previous radiotherapy to the time of re-irradiation was 15.6 (0.4-210.1) months. Separately, the median prescript dose of re-irradiation was 78.0 (28.0-104.9) of BED₁₀. The median survival time in this study was 13.9 months, with 1-, 3-, and 5-year overall survival rates of 53.7%, 29.3%, and 26.6%, respectively. The 1-, 3-, and 5-year local control rates were 90.8%, 84.0%, and 84.0%, respectively. Neurotoxicity was observed in two of 72 treatments (2.8%) assessed after re-irradiation.

CONCLUSION

Re-irradiation for the spine using IMRT seems well-tolerated. Definitive re-irradiation can be a feasible treatment option in patients with the potential for a good prognosis.

Stereotactic body radiotherapy (SBRT) in patients with lung metastases - prognostic factors and long-term survival using patient self-reported outcome (PRO)

OBJECTIVES

The present study aims to evaluate long-term side-effects and outcomes and confirm prognostic factors after stereotactic body radiotherapy (SBRT) of pulmonary lesions. This is the first work that combines the investigated data from patient charts and patient-reported outcome (PRO) up to 14 years after therapy.

MATERIALS AND METHODS

We analyzed 219 patients and 316 lung metastases treated between 2004 and 2019. The pulmonary lesions received a median dose and dose per fraction of 35 Gy (range: 14-60.5 Gy) and 8 Gy (range: 3-20 Gy) to the surrounding isodose. During the last 1.5 years of monitoring, we added PRO assessment to our follow-up routine. We sent an invitation to a web-based survey questionnaire to all living patients whose last visit was more than 6 months ago.

RESULTS

Median OS was 27.6 months. Univariate analysis showed a significant influence on OS for KPS ≥90%, small gross tumor volume (GTV) and planning target volume (PTV), the absence of external metastases, ≤3 pulmonary metastases, and controlled primary tumor. The number of pulmonary metastases and age influenced local control (LC) significantly. During follow-up, physicians reported severe side-effects ≥ grade 3 in only 2.9% within the first 6 months and in 2.5% after 1 year. Acute symptomatic pneumonitis grade 2 was observed in 9.7%, as grade 3 in 0.5%. During PRO assessment, 39 patients were contacted, 38 patients participated, 14 participated twice during follow-up. Patients reported 15 cases of severe side effects (grade ≥ 3) according to PROCTCAE classification. Severe dyspnea (n = 6) was reported mostly.

CONCLUSION

We could confirm excellent local control and low toxicity rates. PROs improve and complement follow-up care. They are an essential measure in addition to the physician-reported outcomes. Future research must be conducted regarding the correct interpretation of PRO data.

Stereotactic robotic body radiotherapy for patients with oligorecurrent pulmonary metastases

BACKGROUND

Our aim is to report treatment efficacy and toxicity of patients treated by robotic (Cyberknife®) stereotactic body radiotherapy (SBRT) for oligorecurrent lung metastases (ORLM). Additionally we wanted to evaluate influence of tumor, patient and treatment related parameters on local control (LC), lung and distant progression free- (lung PFS/Di-PFS) and overall survival (OS).

METHODS

Consecutive patients with up to 5 ORLM (confirmed by FDG PET/CT) were included in this study. Intended dose was 60Gy in 3 fractions (prescribed to the 80% isodose volume). Patients were followed at regular intervals and tumor control and toxicity was prospectively scored. Tumor, patient and treatment data were analysed using competing risk- and Cox regression.

RESULTS

Between May 2010 and March 2016, 104 patients with 132 lesions were irradiated from primary lung carcinoma (47%), gastro-intestinal (34%) and mixed primary histologies (19%). The mean tumor volume was 7.9 cc. After a median follow up of 22 months, the 1, 2 and 3 year LC rate (per lesion) was 89.3, 80.0 and 77.8% respectively. The corresponding (per patient) 1, 2 and 3 years lung PFS were 66.3, 50.0, 42.6%, Di-PFS were 80.5, 64.4, 60.6% and OS rates were 92.2, 80.9 and 72.0% respectively. On univariable analysis, gastro-intestinal (GI) as primary tumor site showed a significant superior local control versus the other primary tumor sites. For OS, significant variables were primary histology and primary tumor site with a superior OS for patients with metastases of primary GI origin. LC was significantly affected by the tumor volume, physical and biologically effective dose coverage. Significant variables in multivariable analysis were BED prescription dose for LC and GI as primary site for OS. The vast majority of patients developed no toxicity or grade 1 acute and late toxicity. Acute and late grade 3 radiation pneumonitis (RP) was observed in 1 and 2 patients respectively. One patient with a centrally located lesion developed grade 4 RP and died due to possible RT-induced pulmonary hemorrhage.

CONCLUSIONS

SBRT is a highly effective local therapy for oligorecurrent lung metastases and could achieve long term survival in patients with favourable prognostic features.

Croton tiglium essential oil compounds have anti-proliferative and pro-apoptotic effects in A549 lung cancer cell lines

As a traditional Chinese medicine, Croton tiglium has the characteristics of laxative, analgesic, antibacterial and swelling. This study aimed to analyze the chemical composition of C. tiglium essential oil (CTEO) extracted from the seeds of C. tiglium and its cytotoxicity and antitumor effect in vitro. Supercritical CO2 fluid extraction technology was used to extract CTEO and the chemical constituents of the essential oil were identified by comparing the retention indices and mass spectra data taken from the NIST library with those calculated based on the C7-C40 n-alkanes standard. In vitro cytotoxicity of the CTEO was assessed against cancer cell lines (A549) and the human normal bronchial epithelial cells (HBE) using the CCK-8 assay. Proliferation was detected by colony formation experiments. Wound scratch and cell invasion assays were used to detect cell migration and invasion. Levels of apoptotic markers, signaling molecules, and cell cycle regulators expression were characterized by Western blot analysis. As the results, twenty-eight compounds representing 92.39% of the total oil were identified in CTEO. The CTEO has significant antitumor activity on A549 cancer cells (IC50 48.38 μg/mL). In vitro antitumor experiments showed that CTEO treatment significantly inhibited the proliferation and migration of A549 cells, disrupted the cell cycle process, and reduced the expression levels of cyclin A, cyclin B and CDK1. CTEO can also reduce mitochondrial membrane potential, activate caspase-dependent apoptosis pathway, and finally induce apoptosis. CTEO may become an effective anti-cancer drug and will be further developed for cancer treatment.

The Prognostic Role of Pretreatment Neutrophil to Lymphocyte Ratio (NLR) in Malignant Adrenal Lesions Treated With Stereotactic Body Radiation Therapy (SBRT)

OBJECTIVE

The objective of this study was to evaluate a single institution's experience with stereotactic body radiotherapy (SBRT) in treating malignant adrenal lesions, as well as the prognostic value of systemic inflammation biomarkers.

MATERIALS AND METHODS

From November 2007 to February 2018, 27 patients with malignant adrenal lesions received 31 SBRT treatments. Outcomes, measured from the date of SBRT, included overall survival (OS), local control (LC), and freedom from progression. Cox proportional hazard model was utilized to identify potential prognostic factors. Tumor response was assessed with PET Response Evaluation Criteria In Solid Tumors (PERCIST)/Response Evaluation Criteria in Solid Tumors (RECIST) criteria. Acute toxicity was evaluated with the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.03 criteria.

RESULTS

Median follow-up for all patients was 8 months. The complete response, partial response, stable disease, and progressive disease rates were 59%, 9%, 32%, and 0%, respectively. One-year LC, OS, and freedom from progression were 77.7%, 38.0%, and 10.0%, respectively. There was a trend toward significance upon multivariate analysis for pretreatment neutrophil to lymphocyte ratio >4.1 to predict inferior OS (adjusted hazard ratio=3.29, P=0.09, 1-year OS: 11% vs. 80%). There were 3 cases (10%) complicated by grade 2 acute toxicity, including nausea and fatigue. There was 1 grade 5 toxicity, as 1 case was complicated by a fatal gastric ulcer occurring 3 months after SBRT to the left adrenal gland (112.5 BED10).

CONCLUSIONS

These results support the limited existing literature, demonstrating that SBRT provides adequate LC for adrenal lesions with minimal toxicity. Pretreatment neutrophil to lymphocyte ratio may serve as a prognostic factor in these patients.

Clinical Features and Prognostic Factor of Thoracic Postoperative Oligo-Recurrence of Non-Small-Cell Lung Cancer

Objective

The study aimed to clarify clinical features and prognostic factors of thoracic oligo-postoperative recurrences that underwent local therapy of non-small-cell lung cancer (NSCLC).

Methods

From 2332 patients of resected pathological stage I–IIIA NSCLC between 2008 and 2015, a total of 542 patients in follow developed recurrence. Thoracic oligo-recurrence was defined as 1–3 loco-regional confined to lung lobe, hilar/mediastinal lymph nodes, bronchial stump, or chest wall. This study included 56 thoracic oligo-recurrences. Local therapy included secondary surgery, stereotactic radiotherapy, radiotherapy with a 45 Gy or higher dose, and proton radiation therapy, performed with radical intent. We retrospectively reviewed the postoperative data and performed the univariate and multivariate analysis by Kaplan-Meier methods and Cox regression models, respectively.

Results

Thoracic Oligo-recurrence was identified in 56(542,10.3%) patients, mainly in lung lobe(n=22,39%) and regional lymph nodes(n=19,34%). Compared with distant oligo-recurrences, more of the thoracic oligo-recurrences were II–III in pathological stage at initial surgery(p=0.002) and less were adenocarcinoma(p=0.005). The 5-year postoperative survival rate and postoperative progression-free survival rate of thoracic oligo-recurrence were 10.8% and 6.7%, respectively. Median post-recurrence survival (PRS) was 31 months, and the median postoperative progression-free survival (PR-PFS) was 17 months. Multivariate analyses revealed that time to recurrence ≥ 12 months was associated with improved PRS [odds ratio (OR) 0.74, confidence interval (CI) 0.65–0.85], and regional lymph node oligo-recurrence was associated with poor PRS [OR 1.48, CI 1.38–1.60]. All the five long-term (≥5-year) progression-free survivors were with a solitary pulmonary recurrence.

Conclusion

Thoracic postoperative oligo-recurrence of non-small-cell lung cancer is a limited but highly heterogeneous population, with different prognosis at different recurrence sites. Local therapy for thoracic oligo-recurrence of NSCLC achieved favourable PRS in a selected population. Pulmonary solitary oligo-recurrence may achieve a long survival time.

Stereotactic Body Radiation Therapy of Adrenal Metastases: A Pooled Meta-Analysis and Systematic Review of 39 Studies with 1006 Patients

PURPOSE

To perform a systematic review and pooled meta-analysis of adrenal metastasis stereotactic body radiation therapy (SBRT) outcomes, treatment characteristics, and toxicity to define the efficacy and propose guidelines for intervention.

METHODS AND MATERIALS

We performed a comprehensive literature search of the Embase and PubMed databases of studies reporting outcome or toxicity data for photon-based SBRT of adrenal metastases in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We then conducted a meta-analysis to estimate pooled overall response, local control (LC), and overall survival and analyzed these outcomes in the context of dosimetric parameters and toxicity using metaregression.

RESULTS

Thirty-nine studies published between 2009 and 2019 reporting outcomes on 1006 patients were included. The median follow-up was 12 months, and the median biological equivalent dose (BED10, alpha/beta = 10) was 67 Gy. The pooled overall response was 54.6% (95% confidence interval [CI], 46.5%-62.5%). The pooled 1- and 2-year rates of LC were 82% (95% CI, 74%-88%) and 63% (95% CI, 50%-74%), respectively, and the pooled 1- and 2-year overall survival rates were 66% (95% CI, 57%-74%) and 42% (95% CI, 31%-53%), respectively. There was a strong positive association between SBRT dose and 1- and 2-year LC (P < .0001, P = .0002) and an association with 2-year OS (P = .03). Based on a metaregression of dose and LC, BED10 of 60 Gy, 80 Gy, and 100 Gy predicted 1-year LC of 70.5%, 84.8%, and 92.9% and 2-year LC of 47.8%, 70.1%, and 85.6%, respectively. The overall rate of grade 3 or higher toxicity was 1.8%.

CONCLUSIONS

SBRT of adrenal metastases provides good 1-year LC with an excellent safety profile, and dose escalation may be associated with improved LC. Prospective studies are needed to validate these findings and determine whether there are subsets of patients for whom adrenal metastasis-directed SBRT may confer a survival advantage.

Tumor biology and multidisciplinary strategies of oligometastasis in gastrointestinal cancers

More than 70% of gastrointestinal (GI) cancers are diagnosed with metastases, leading to poor prognosis. For some cancer patients with limited sites of metastatic tumors, the term oligometastatic disease (OMD) has been coined as opposed to systemic polymetastasis (PMD) disease. Stephan Paget first described an organ-specific pattern of metastasis in 1889, now known as the "seed and soil" theory where distinct cancer types are found to metastasize to different tumor-specific sites. Our understanding of the biology of tumor metastasis and specifically the molecular mechanisms driving their formation are still limited, in particular, as it relates to the genesis of oligometastasis. In the following review, we discuss recent advances in general understanding of this metastatic behavior including the role of specific signaling pathways, various molecular features and biomarkers, as well as the interaction of carcinoma cells with their tissue microenvironments (both primary and metastatic niches). The unique features that underlie OMD provide potential targets for localized therapy. As it relates to clinical practice, OMD is emerging as treatable with surgical resection and/or other local therapy options. Strategies currently being applied in the clinical management of OMD will be discussed including surgical, radiation-based therapy, ablation procedures, and the results of emerging clinical trials involving immunotherapy.

Treatment modes for EGFR mutations in patients with brain metastases from non-small cell lung cancer: controversy, causes, and solutions

Brain metastasis from non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations is a hot research topic, but also a difficulty in targeted NSCLC therapy, and is also the focus of controversy in the field of lung cancer treatment. According to medical oncology, asymptomatic patients were initially treated with targeted therapy, followed by local radiotherapy when symptoms present or disease progresses. However, from the perspective of the discipline of radiotherapy, brain metastases need to be treated before drug resistance, as it may affect survival. Controversies between disciplines have brought much confusion to the treatment choices of clinicians. We summarized and discussed relevant literatures in this article to seek the truth in providing reference in clinical practice for treating diseases and solving problems.

Integration of radiotherapy and immunotherapy for treatment of oligometastases

Metastasis is the leading cause of cancer-related mortality and remains one of the prevailing challenges in cancer treatment. Most patients with metastatic disease are treated with systemic agents, which prolong survival and improve symptoms but are typically not curative. The oligometastatic hypothesis challenges the perspective that metastasis is an invariably disseminated process, and proposes a biological spectrum of metastatic virulence. Mounting evidence supports the idea that patients with numerically and spatially restricted sites of metastases, termed oligometastases, can achieve prolonged survival following metastasis-directed therapies, such as surgery or radiotherapy. Improvements in clinical and molecular staging of metastatic disease, as well as integration of effective systemic therapies with localised interventions, might achieve better outcomes for patients with diverse metastatic states. In this Series paper, we propose a rationale for the integration of immune checkpoint inhibitors with radiotherapy to advance the potential for effective treatment along the spectrum of disease, with emphasis on how immunotherapy can potentiate radiotherapy treatment in the oligometastatic setting.

Use of Aggressive Surveillance for Locoregional Endometrial Cancer After Local Therapy

PURPOSE/OBJECTIVES

Current guidelines do not recommend routine surveillance imaging as part of follow-up care for patients treated for locoregional endometrial carcinoma. This study seeks to determine the potential benefit of routine surveillance imaging by evaluating outcomes of patients whose recurrences were detected on routine surveillance compared to those whose recurrences were identified after presenting with symptoms.

MATERIALS/METHODS

We conducted a retrospective review of patients who developed recurrence after surgical treatment, with or without adjuvant therapy, for locoregional endometrial carcinoma. A total of 149 patients were identified with adequate clinical information regarding the recurrence. Cox proportional hazards regression analysis was used to estimate overall survival and progression-free survival.

RESULTS

The median age of patients at diagnosis was 69.2 years (range, 38.0-99.5 years). Initial stages included stage I, 49.7%; stage II, 10.1%; stage III, 38.3%; and stage IV, 1.3%. Histologic diagnoses included endometrioid adenocarcinoma, 48.3%; and other diagnoses (including papillary serous carcinoma, clear cell carcinoma, and carcinosarcoma), 51.7%. Patients were initially treated with a variety of therapies: surgery alone in 20.8%, surgery and radiation in 25.5%, surgery and chemotherapy in 12.1%, and trimodality therapy in 41.6%. Sites of recurrence included 20.8% vaginal, 14.8% pelvic and 64.4% distant sites. Recurrences were detected asymptomatically in 86 patients (57.7%) and symptomatically in 63 patients (42.3%). Of those detected asymptomatically, 80.2% were detected by imaging. Overall, when comparing symptomatic versus asymptomatic recurrences, there was no difference in overall survival (hazard ratio, 1.24; 95% confidence interval, 0.84-1.83; P = 0.29) or progression-free survival (hazard ratio, 1.14; 95% confidence interval, 0.77-1.70; P = 0.52).

CONCLUSIONS

Patients who develop asymptomatic recurrences of their endometrial carcinoma do not seem to have a better prognosis than those who present with symptomatic recurrences. Thus, these results do not support routine imaging surveillance for patients treated for locoregional endometrial carcinoma. Further prospective evaluation is needed.

How rapid advances in imaging are defining the future of precision radiation oncology

Imaging has an essential role in the planning and delivery of radiotherapy. Recent advances in imaging have led to the development of advanced radiotherapy techniques—including image-guided radiotherapy, intensity-modulated radiotherapy, stereotactic body radiotherapy and proton beam therapy. The optimal use of imaging might enable higher doses of radiation to be delivered to the tumour, while sparing normal surrounding tissues. In this article, we review how the integration of existing and novel forms of computed tomography, magnetic resonance imaging and positron emission tomography have transformed tumour delineation in the radiotherapy planning process, and how these advances have the potential to allow a more individualised approach to the cancer therapy. Recent data suggest that imaging biomarkers that assess underlying tumour heterogeneity can identify areas within a tumour that are at higher risk of radio-resistance, and therefore potentially allow for biologically focussed dose escalation. The rapidly evolving concept of adaptive radiotherapy, including artificial intelligence, requires imaging during treatment to be used to modify radiotherapy on a daily basis. These advances have the potential to improve clinical outcomes and reduce radiation-related long-term toxicities. We outline how recent technological advances in both imaging and radiotherapy delivery can be combined to shape the future of precision radiation oncology.

NRG Oncology/RTOG 0438: A Phase 1 Trial of Highly Conformal Radiation Therapy for Liver Metastases

PURPOSE

This study aimed to determine the feasibility and maximally tolerated dose of hypofractionated, conformal radiation therapy (RT) in patients with liver metastases.

METHODS AND MATERIALS

Nonsurgical patients with ≤5 liver metastases (sum of maximal diameter of all lesions ≤8 cm) were included in the study. There were 4 dose levels: 35 Gy, 40 Gy (starting level), 45 Gy, and 50 Gy, in 10 fractions. The clinical target volume included metastases identified on contrast computed tomography or magnetic resonance imaging with a 5-mm margin within the liver. The planning target volume margin ranged from 4 to 30 mm, depending on breathing motion. Dose-limiting toxicities were defined as RT-related grade ≥4 hepatic or gastrointestinal toxicities or thrombocytopenia occurring within 90 days of the start of RT.

RESULTS

A total of 26 patients with metastases from colorectal (8 patients), breast (7 patients) and other malignancies (11 patients) were enrolled between November 2005 and December 2010. Twenty-three patients were evaluable (8, 7, and 8 on the 40, 45, and 50 Gy dose levels, respectively). Two patients assigned to 50 Gy received 35 Gy owing to normal tissue limits, so 2 additional patients were treated to 50 Gy. There were no dose-limiting toxicities on any of the dose levels. On the 45 Gy dose level, 1 patient developed reversible grade 3 enteritis (37 days from RT start) and diarrhea (22 days); another patient developed grade 3 lymphopenia (23 days). At the 50 Gy dose level, 1 patient had grade 3 hyperglycemia (74 days), and another patient developed grade 3 lymphopenia (13 days), colonic hemorrhage (325 days), and colonic gastrointestinal obstruction (325 days). With a potential median follow-up of 66.1 months (range, 34.6-89.0 months), no other late toxicities were observed.

CONCLUSIONS

Treatment of liver metastases with 50 Gy in 10 fractions was feasible and safe in a multi-institutional setting.

Stereotactic Radiotherapy for Oligometastasis

Oligometastatic disease is defined as “a condition with a few metastases arising from tumors that have not acquired a potential for widespread metastases.” Its behavior suggests a transitional malignant state somewhere between localized and metastatic cancer. Treatment of oligometastatic disease is expected to achieve long-term local control and to improve survival. Historically, patients with oligometastases have often undergone surgical resection since it was anecdotally believed that surgical resection could result in progression-free or overall survival benefits. To date, no prospective randomized trials have demonstrated surgery-related survival benefits. Short courses of highly focused, extremely high-dose radiotherapies (e.g., stereotactic radiosurgery and stereotactic ablative body radiotherapy (SABR)) have frequently been used as alternatives to surgery for treatment of oligometastasis. A randomized study has demonstrated the overall survival benefits of stereotactic radiosurgery for solitary brain metastasis. Following the success of stereotactic radiosurgery, SABR has been widely accepted for treating extracranial metastases, considering its efficacy and minimum invasiveness. In this review, we discuss the history of and rationale for the local treatment of oligometastases and probe into the implementation of SABR for oligometastatic disease.

Salvage radiotherapy with simultaneous integrated boost in non small-cell lung cancer patients with mediastinal relapse after surgery: a pilot study

Background

The aim of our study was to evaluate feasibility, toxicity profile and local control of salvage intensity modulated radiotherapy (IMRT) delivered with simultaneous integrated boost (SIB) associated or not to concomitant weekly cisplatin in patients affected by NSCLC with mediastinal nodal recurrence after surgery. Patterns of recurrence, outcomes and prognostic factors were assessed.

Methods

Fourteen consecutive patients received 25 fractions of 50Gy/2Gy to the elective nodal stations and boost up to 62.5Gy/2.5Gy to the macroscopic lymph node metastases. Concomitant weekly cisplatin (40 mg/m²) was administered to 8 (57.1%) patients.

Results

Five (35.7%) patients experienced grade 2 pneumonitis and 5 (35.7%) patients had grade 2 esophagitis. One case of grade 3 pneumonitis occurred and was successfully treated with antibiotics and steroids with no sequelae. No patient recurred locally in the boost volume (local control 100%). Loco-regional control was 79% with 3 patients that developed nodal recurrence principally marginal to the elective volume. Seven patients developed distant metastases. Median PFS was 7 months. The nodal involvement of station 7 was associated to a significantly lower median metastasis-free survival (4 months vs. not reached, p = 0.036).

Conclusions

Salvage radiotherapy with IMRT-SIB is a feasible and a well-tolerated treatment option for mediastinal recurrent NSCLC after surgery. The role of more intensified radiation regimens and association to systemic therapy remain to be evaluated in larger cohorts.

Prospective Immunophenotyping of CD8+ T Cells and Associated Clinical Outcomes of Patients With Oligometastatic Prostate Cancer Treated With Metastasis-Directed SBRT

PURPOSE

This study examined the effects of metastasis-directed stereotactic body radiation therapy (mdSBRT) on CD8⁺ T-cell subpopulations and correlated post-mdSBRT immunophenotypic responses with clinical outcomes in patients with oligometastatic prostate cancer (OPCa).

METHODS AND MATERIALS

Peripheral blood mononuclear cells were prospectively isolated from 37 patients with OPCa (≤3 metastases) who were treated with mdSBRT. Immunophenotyping identified circulating CD8⁺ T-cell subpopulations, including tumor-reactive (T_TR), effector memory, central memory (T_CM), effector, and naïve T cells from samples collected before and after mdSBRT. Univariate Cox proportional hazards regression was used to assess whether changes in these T-cell subpopulations were potential risk factors for death and/or progression. The Kaplan-Meier method was used for survival. Cumulative incidence for progression and new distant metastasis weas estimated, considering death as a competing risk.

RESULTS

Median follow-up was 39 months (interquartile range, 34-43). Overall survival at 3 years was 78.2%. Cumulative incidence for local progression and new distant metastasis at 3 years was 16.5% and 67.6%, respectively. Between baseline and day 14 after mdSBRT, an increase in the T_CM cell subpopulation was associated with the risk of death (hazard ratio, 1.22 [95% confidence interval, 1.02-1.47]; P = .033), and an increase in the T_TR cell subpopulation was protective against the risk of local progression (hazard ratio, 0.80 [95% confidence interval, 0.65-0.98]; P = .032).

CONCLUSIONS

An increase in the T_TR cell subpopulation was protective against the risk of disease progression, and an increase in the T_CM cell subpopulation was associated with the risk of death in patients with OPCa treated with mdSBRT. Disease control may be further improved by better understanding the CD8⁺ T-cell subpopulations and by enhancing their antitumor effect.

A phase I dose-escalation trial of stereotactic ablative body radiotherapy for non-spine bone and lymph node metastases (DESTROY-trial)

Background

In an oligometastatic setting, metastasis-directed treatment could render patients disease free, possibly for a protracted interval. Stereotactic ablative radiotherapy (SABR) is one of the treatment modalities that can be offered to these patients. In addition, the radiobiological qualities of SABR are promising for the use in perceived radioresistant tumours. There is also emerging evidence that SABR can stimulate the immune response, and a specific therapeutic window may exist for the optimal use of radiotherapy as an immune adjuvant. However, when SABR is considered for non-spine bone or lymph node metastases, the optimal fractionation schedule is not yet known.

Methods

The DESTROY-trial is a non-randomized prospective phase I trial determining a regimen of choice for patients with non-spine bone and lymph node metastases. A total of 90 patients will be included in three different treatment regimens. They will be offered stereotactic ablative radiotherapy in 5, 3 or 1 fractions. Dose-limiting toxicity will be recorded as primary endpoint. Acute and late toxicity, local response and local recurrence, and progression-free survival are secondary endpoints. Liquid biopsies will be collected throughout the course of this study from the second fractionation schedule on.

Discussion

Despite its almost universal use in (oligo-)metastatic patients, the level of evidence supporting radical local treatment in general, and stereotactic radiotherapy in particular, is low. This prospective phase I trial will evaluate different SABR regimens for metastases and the differences in immune-stimulatory effects.

Trial registration

The Ethics committee of the GZA Hospitals (B099201732915) approved this study on 05/07/2017. Amendment for translational research was approved on 06/02/2018. Trial registered on Clinicaltrials.gov (NCT03486431) on 03/04/2018 – Retrospectively registered.

Proton therapy for hepatocellular carcinoma: Current knowledges and future perspectives

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death, as few patients can be treated with currently available curative local modalities. In patients with HCC where curative modalities are not feasible, radiation therapy (RT) has emerged as an alternative or combination therapy. With the development of various technologies, RT has been increasingly used for the management of HCC. Among these advances, proton beam therapy (PBT) has several unique physical properties that give it a finite range in a distal direction, and thus no exit dose along the beam path. Therefore, PBT has dosimetric advantages compared with X-ray therapy for the treatment of HCC. Indeed, various reports in the literature have described the favorable clinical outcomes and improved safety of PBT for HCC patients compared with X-ray therapy. However, there are some technical issues regarding the use of PBT in HCC, including uncertainty of organ motion and inaccuracy during calculation of tissue density and beam range, all of which may reduce the robustness of a PBT treatment plan. In this review, we discuss the physical properties, current clinical data, technical issues, and future perspectives on PBT for the treatment of HCC.

Prognostic factors in stereotactic body radiotherapy of lung metastases

PURPOSE

The aim of this study was to evaluate prognostic factors in patients with lung metastases who undergo lung stereotactic body radiotherapy (SBRT).

MATERIALS AND METHODS

A total of 87 patients with 129 lung metastases who underwent SBRT between November 2004 and May 2012 were enrolled in this retrospective study. The patient collective consisted of 54 men (62.1%) and 33 women (37.9%); the median age was 65 years (range 36-88). The Karnofsky performance index was ≥70% (median 90%) for all cases, but one (60%). Adverse effects were categorized using the CTCAE 4.0 classification system. Retrospective analyses regarding patients' characteristics, progression-free survival (PFS), overall survival (OS), disease-specific survival (DSS), and local tumor control rates (LTC) were performed.

RESULTS

On univariate and multivariate analysis OS, DSS, and PFS were significantly (p < 0.05) better for patients with ≤3 lung metastases; no extrathoracic metastases at the time of the SBRT; a gross tumor volume (GTV) <7.7 cm³ and patients that received a staging that included positron emission tomography with fluorine 18 fluorodeoxyglucose/computed tomography (FDG-PET/CT) imaging. Furthermore, a longer OS was observed if newly diagnosed metastases during follow-up were limited to the lung (median survival: 43.7 months versus 21.7 months; p = 0.023).

CONCLUSION

The number and pattern of metastases, and the size of the target volume are strong predictors for the outcome of patients receiving SBRT of lung tumors. FDG-PET/CT should be part of pretherapeutic staging before SBRT.

Survival outcomes following aggressive treatment of oligometastatic breast cancer: a systematic review protocol

REVIEW QUESTION/OBJECTIVE

The objective of this systematic review is to assess the effectiveness of aggressive treatment of oligometastatic breast cancer (OMBC) on survival outcomes by conducting a meta-analysis of current available evidence.More specifically, the objectives are to identify the effectiveness of intensified multidisciplinary treatment with aggressive locoregional therapies on survival time, five-year survival rates and disease free survival. The population is adult women (18 years and over) with OMBC defined as single or few (five or less) metastases limited to a single organ and the comparative group is conventional palliative treatment aimed at disease control. Secondary objectives to be assessed will be adverse outcomes associated with intensified treatment regimes.

Stereotactic ablative body radiotherapy (SABR) for inoperable, chemorefractory retroperitoneal lymph node relapse from non seminomatous germ cell tumour of testis: a case report

We describe a case of non-seminomatous germ cell tumour (NSGCT) of the testis with oligorecurrence in para-aortic nodal mass, which was inoperable and chemorefractory. Conventionally fractionated radiotherapy in this setting is generally believed to achieve poor results, because the dose is limited by the tolerance of surrounding normal tissues. Use of stereotactic ablative body radiotherapy (SABR) for para-aortic nodal recurrence from a few sites has been reported; its application in NSGCT has not been described in literature to our knowledge. SABR allowed us to deliver highly precise, ablative dose of radiation to the recurrent para-aortic nodal mass with long-term disease control (more than 6 years). The ablative dose delivered with SABR proved to be effective in NSGCT, traditionally considered radioresistant. While, in the present case SABR was delivered due to the inoperability of the lesion, further data on its successful use in NSGCT recurrences is warranted.

Prognostic Utility of Histological Growth Patterns of Colorectal Lung Oligometastasis

Background

Patients with resectable colorectal lung oligometastasis (CLOM) demonstrate a heterogeneous oncological outcome. However, the parameters for predicting tumor aggressiveness have not yet been fully investigated in CLOM. This study was performed to determine the prognostic value of histological growth patterns in patients who underwent surgery for CLOM.

Methods

The study included 92 patients who were diagnosed with CLOM among the first resection cases. CLOMs grow according to three histological patterns: aerogenous, pushing, and desmoplastic patterns. The growth patterns were evaluated on archival hematoxylin and eosin–stained tissue sections.

Results

The aerogenous pattern was found in 29.4% (n=27) of patients, the pushing pattern in 34.7% (n=32), the desmoplastic pattern in 6.5% (n=6), and a mix of two growth patterns in 29.4% (n=27). The size of the aerogenous pattern was significantly smaller than that of metastases with other patterns (p=.033). Kaplan-Meier analysis demonstrated that patients showing an aerogenous pattern appeared to have a poorer prognosis, which was calculated from the time of diagnosis of the CLOM (p=.044). The 5-year survival rate from the diagnosis of colorectal cancer tended to be lower in patients with an aerogenous pattern than in those who had a non-aerogenous pattern; however, the difference was marginally significant (p=.051). In the multivariate Cox analysis, the aerogenous pattern appeared as an independent predictor of poor overall survival (hazard ratio, 3.122; 95% confidence interval, 1.196 to 8.145; p=.020).

Conclusions

These results suggest that the growth patterns may play a part as a histology-based prognostic parameter for patients with CLOM.