Efficacy of stereotactic body radiotherapy and response prediction using artificial intelligence in oligometastatic gynaecologic cancer.

PURPOSE: We present a large real-world multicentric dataset of ovarian, uterine and cervical oligometastatic lesions treated with SBRT exploring efficacy and clinical outcomes. In addition, an exploratory machine learning analysis was performed. METHODS: A pooled analysis of gynecological oligometastases in terms of efficacy and clinical outcomes as well an exploratory machine learning model to predict the CR to SBRT were carried out. The CR rate following radiotherapy (RT) was the study main endpoint. The secondary endpoints included the 2-year actuarial LC, DMFS, PFS, and OS. RESULTS: 501 patients from 21 radiation oncology institutions with 846 gynecological metastases were analyzed, mainly ovarian (53.1%) and uterine metastases(32.1%).Multiple fraction radiotherapy was used in 762 metastases(90.1%).The most frequent schedule was 24 Gy in 3 fractions(13.4%). CR was observed in 538(63.7%) lesions. The Machine learning analysis showed a poor ability to find covariates strong enough to predict CR in the whole series. Analyzing them separately, in uterine cancer, if RT dose≥78.3Gy, the CR probability was 75.4%; if volume was <13.7 cc, the CR probability became 85.1%. In ovarian cancer, if the lesion was a lymph node, the CR probability was 71.4%; if volume was <17 cc, the CR probability rose to 78.4%. No covariate predicted the CR for cervical lesions. The overall 2-year actuarial LC was 79.2%, however it was 91.5% for CR and 52.5% for not CR lesions(p < 0.001). The overall 2-year DMFS, PFS and OS rate were 27.3%, 24.8% and 71.0%, with significant differences between CR and not CR. CONCLUSIONS: CR was substantially associated to patient outcomes in our series of gynecological cancer oligometastatic lesions. The ability to predict a CR through artificial intelligence could also drive treatment choices in the context of personalized oncology.

Concurrent Use of Abemaciclib and Radiotherapy in Metastatic Breast Cancer Patients: A Single-Center Experience.

INTRODUCTION: There is little evidence regarding the safety and efficacy of the combination of abemaciclib plus radiotherapy (RT). The majority of studies investigated the combination of RT with palbociclib or ribociclib reporting that hematological toxicity is common. Given the unique toxicity profile of abemaciclib with greater gastrointestinal toxicity compared to hematological toxicity, we wanted to evaluate the toxicity of the combination with RT in metastatic breast cancer (BC) patients. METHODS: Patients with histologically proven metastatic or locally advanced BC treated with RT and concurrent abemaciclib were selected. Toxicity was assessed according to the NCI-CTCAE V4.0. RESULTS: Thirty-two metastatic sites were treated in 19 patients and analyzed. All patients received abemaciclib during the RT course. A total of 68% of patients received a full dose of abemaciclib during RT. Also, 71.9% of patients received a palliative intent (median dose = 30 Gy, range = 8-30 Gy), and 26.3% were treated for 9 oligo-metastatic or oligo-progressive sites of disease with stereotactic body RT (median dose = 30 Gy, range 21-30 Gy, given in 3-5 fractions). Overall, the rate of G3 toxicity was 15.7%. The rate of G3 hematological toxicity was 10.6% (2/19 patients, one G3 neutropenia and one G3 anemia). No patient presented diarrhea, including those treated for RT sites close to the bowel. One patient developed G3 skin toxicity. Pain significantly improved after RT (mean value NRS pre-RT = 3.9, SD = 3.07; mean value NRS after RT = 0.9, SD = 0.46; p < 0.0001). CONCLUSION: Abemaciclib and concomitant RT seem well tolerated showing acceptable toxicity.

Definitive chemoradiation in vulvar squamous cell carcinoma: outcome and toxicity from an observational multicenter Italian study on vulvar cancer (OLDLADY 1.1).

BACKGROUND: Vulvar carcinoma is a rather uncommon gynecological malignancy affecting elderly women and the treatment of loco-regional advanced carcinoma of the vulva (LAVC) is a challenge for both gynecologic and radiation oncologists. Definitive chemoradiation (CRT) is the treatment of choice, but with disappointing results. In this multicenter study (OLDLADY-1.1), several institutions have combined their retrospective data on LAVC patients to produce a real-world dataset aimed at collecting data on efficacy and safety of CRT. METHODS: The primary study end-point was 2-year-local control (LC), secondary end-points were 2-year-metastasis free-survival (MFS), 2-year-overall survival (OS) and the rate and severity of acute and late toxicities. Participating centers were required to fill data sets including age, stage, histology, grading as well as technical/dosimetric details of CRT. Data about response, local and regional recurrence, acute and late toxicities, follow-up and outcome measures were also collected. The toxicity was a posteriori documented through the Common Terminology Criteria for Adverse Events version 5 scale. RESULTS: Retrospective analysis was performed on 65 patients with primary or recurrent LAVC treated at five different radiation oncology institutions covering 11-year time interval (February 2010-November 2021). Median age at diagnosis was 72 years (range 32-89). With a median follow-up of 19 months (range 1-114 months), 2-year actuarial LC, MFS and OS rate were 43.2%, 84.9% and 59.7%, respectively. In 29 patients (44%), CRT was temporarily stopped (median 5 days, range 1-53 days) due to toxicity. The treatment interruption was statistically significant at univariate analysis of factors predicting LC (p: 0.05) and OS rate (p: 0.011), and it was confirmed at the multivariate analysis for LC rate (p: 0.032). In terms of toxicity profile, no G4 event was recorded. Most adverse events were reported as grade 1 or 2. Only 14 acute G3 toxicities, all cutaneous, and 7 late G3 events (3 genitourinary, 3 cutaneous, and 1 vaginal stenosis) were recorded. CONCLUSION: In the context of CRT for LAVC, the present study reports encouraging results even if there is clearly room for further improvements, in terms of both treatment outcomes, toxicity and treatment interruption management.

Efficacy and safety of stereotactic body radiotherapy (SBRT) in oligometastatic/persistent/recurrent ovarian cancer: a prospective, multicenter phase II study (MITO-RT3/RAD).

BACKGROUND: Stereotactic body radiotherapy (SBRT) has shown promising results in the clinical setting of oligometastatic, persistent, or recurrent disease in several malignancies including ovarian cancer. PRIMARY OBJECTIVE: The MITO-RT3/RAD trial is a prospective, multicenter phase II study aimed at identifying potential predictors of response and clinical outcome after SBRT treatment. STUDY HYPOTHESIS: Radiotherapy delivered by pre-defined SBRT treatment schedules and shared constraints could improve the rate of complete response. TRIAL DESIGN: All patients accrued will be treated with a radiotherapy dose in the range of 30-50 Gy by 1, 3, or 5 SBRT daily fractions to all sites of active metastatic disease according to diagnostic imaging. Schedules of treatment and dose prescription have been established before considering target sites and healthy organ dose constraints. Follow-up and monitoring of side effects will be carried out every 3 months for the first year with imaging and clinical evalutation, and every 4 months within the second year; thereafter, surveillance will be carried out every 6 months. The best response on a per lesion basis will be evaluated by computed tomographic (CT) scan, positron emission tomography/CT, or magnetic resonance imaging in case of brain lesions, every 3 months. MAJOR INCLUSION/EXCLUSION CRITERIA: The study includes patients with oligometastatic, persistent, or recurrent ovarian cancer for which salvage surgery or other local therapies are not feasible due to any relative contra-indication to further systemic therapy because of serious co-morbidities, previous severe toxicity, unavailability of potentially active systemic therapy, or patient refusal. PRIMARY ENDPOINT: The primary endpoint of the study is the clinical complete response rate to SBRT by imaging on a per lesion basis. SAMPLE SIZE: Approximately 205 lesions will be treated (90 lymph nodes and 115 parenchyma lesions). ESTIMATED DATES FOR COMPLETING ACCRUAL AND PRESENTING RESULTS: Fifty-two centers have expressed their intention to participate. Enrollment should be completed by March 2023 and analysis will be completed in September 2023. TRIAL REGISTRATION: NCT04593381.

Stereotactic body radiotherapy in oligometastatic cervical cancer (MITO-RT2/RAD study): a collaboration of MITO, AIRO GYN, and MaNGO groups.

OBJECTIVE: This retrospective, multicenter study analyzes the efficacy and safety of stereotactic body radiotherapy in a large cohort of patients with oligometastatic/persistent/recurrent cervical cancer. METHODS: A standardized data collection from several radiotherapy centers that treated patients by stereotactic body radiotherapy between March 2006 and February 2021 was set up. Clinical and stereotactic body radiotherapy parameters were collected. Objective response rate was defined as a composite of complete and partial response, while clinical benefit included objective response rate plus stable disease. Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer and Common Terminology Criteria for Adverse Events scales were used to grade toxicities. The primary endpoints were the rate of complete response to stereotactic body radiotherapy, and the 2 year actuarial local control rate on a 'per lesion' basis. The secondary end points were progression-free survival and overall survival, as well as toxicity. RESULTS: A total of 83 patients with oligometastatic/persistent/recurrent cervical cancer bearing 125 lesions treated by stereotactic body radiotherapy at 15 different centers were selected for analysis. Of the sites of metastatic disease, lymph node metastases were most common (55.2%), followed by parenchyma lesions (44.8%). Median total dose was 35 Gy (range 10-60), in five fractions (range 1-10), with a median dose/fraction of 7 Gy (range 4-26). Complete, partial, and stable response were found in 73 (58.4%), 29 (23.2%), and 16 (12.8%) lesions, respectively, reaching 94.4% of the clinical benefit rate. Forty-six (55.4%) patients had a complete response. Patients achieving complete response on a 'per lesion' basis experienced a 2 year actuarial local control rate of 89.0% versus 22.1% in lesions not achieving complete response (p<0.001). The 2 year actuarial progression-free survival rate was 42.5% in patients with complete response versus 7.8% in patients with partial response or stable or progressive disease (p=0.001). The 2 year actuarial overall survival rate was 68.9% in patients with complete response versus 44.3% in patients with partial response or stable or progressive disease (p=0.015). Fifteen patients (18.1%) had mild acute toxicity, totaling 29 side events. Late toxicity was documented in four patients (4.8%) totaling seven adverse events. CONCLUSION: Our analysis confirmed the efficacy of stereotactic body radiotherapy in oligometastatic/persistent/recurrent cervical cancer patients. The low toxicity profile encourages the wider use of stereotactic body radiotherapy in this setting.

Early GLS changes detection after chemoradiation in locally advanced non-small cell lung cancer (NSCLC).

PURPOSE: Chemoradiation is the standard treatment in patients with locally advanced non-small-cell lung cancer (LA-NSCLC), and thanks to the recent combination with immunotherapy, median survival has unexpectedly improved. This study aims to evaluate early changes in cardiac function after chemoradiotherapy (CRT) in LA-NSCLC by multimodal use of advanced imaging techniques. MATERIALS AND METHODS: This is a prospective, observational cohort study. At the beginning of combined treatment, screening tests including blood samples, electrocardiogram (ECG), echocardiographic examination (TTE), and cardiac magnetic resonance were performed in all patients with LA-NSCLC. ECG and cardiac marker assays were performed weekly during treatment. ECG and TTE were performed at month 1 (M1) and month 3 (M3) after the end of CRT. RESULTS: This preliminary analysis included thirty-four patients with a mean age of 69.5 years. The median follow-up was 27.8 months. 62% of patients were in stage IIIA. Radiation therapy was delivered with a median total dose of 60 Gy with conventional fractionation. All patients were treated with concurrent CRT, and 65% of cases were platinum-based therapy. Global longitudinal strain (GLS) and ejection fraction (EF) progressively decreased from baseline to M1 and M3. There was a strong correlation between GLS and EF reduction (at M1: p = 0.034; at M3: p = 0.018). Cardiac arrhythmias occurred in eight patients (23.5%) at a mean follow-up of 15.8 months after CRT. CONCLUSIONS: Reduction in GLS is an early sign occurring after the end of CRT for LA-NSCLC. Future studies are needed to identify variables that can increase the risk of cardiac events in this patient population to implement adequate damage prevention strategies.

Observational multicenter Italian study on vulvar cancer adjuvant radiotherapy (OLDLADY 1.2): a cooperation among AIRO Gyn, MITO and MaNGO groups.

BACKGROUND: Adjuvant radiotherapy (aRT) has been shown to reduce the risk of local relapse in vulvar cancer (VC). In this multicentre study (OLDLADY-1.2), several Institutions have combined their retrospective data on VC patients to produce a real-world dataset aimed at collecting data on efficacy and safety of aRT. METHODS: The primary study end-point was the 2-year-local control, secondary end-points were the 2-year-metastasis free-survival, the 2-year-overall survival and the rate and severity of acute and late toxicities. Participating centres were required to fill data sets including age, stage, tumor diameter, type of surgery, margin status, depth of invasion, histology, grading as well technical/dosimetric details of radiotherapy. Data about response, local and regional recurrence, acute and late toxicities, follow-up and outcome measures were also collected. RESULTS: One hundred eighty-one patients with invasive VC from 9 Institutions were retrospectively identified. The majority of patients were stage III (63%), grade 2 (62.4%) squamous carcinoma (97.2%). Positive nodes were observed in 117 patients (64.6%), moreover tumor diameter > 4 cm, positive/close margins and depth of invasion deeper than 5 mm were found in 59.1%, 38.6%, 58% of patients, respectively. Sixty-one patients (33.7%) received adjuvant chemoradiation, and 120 (66.3%) received radiotherapy alone. aRT was started 3 months after surgery in 50.8% of patients. Prescribed volumes and doses heterogeneity was recorded according to margin status and nodal disease. Overall, 42.5% locoregional recurrences were recorded. With a median follow-up of 27 months (range 1-179), the 2-year actuarial local control rate, metastasis free and overall survival were 68.7%, 84.5%, and 67.5%, respectively. In term of safety, aRT leads to a prevalence of acute skin toxicity with a low incidence of severe toxicities. CONCLUSIONS: In the context of aRT for VC the present study reports a broad spectrum of approaches which would deserve greater standardization in terms of doses, volumes and drugs used.

A Large, Multicenter, Retrospective Study on Efficacy and Safety of Stereotactic Body Radiotherapy (SBRT) in Oligometastatic Ovarian Cancer (MITO RT1 Study): A Collaboration of MITO, AIRO GYN, and MaNGO Groups.

BACKGROUND: Recent studies have reported improvement of outcomes (progression-free survival, overall survival, and prolongation of androgen deprivation treatment-free survival) with stereotactic body radiotherapy (SBRT) in non-small cell lung cancer and prostate cancer. The aim of this retrospective, multicenter study (MITO RT-01) was to define activity and safety of SBRT in a very large, real-world data set of patients with metastatic, persistent, and recurrent ovarian cancer (MPR-OC). MATERIALS AND METHODS: The endpoints of the study were the rate of complete response (CR) to SBRT and the 24-month actuarial local control (LC) rate on "per-lesion" basis. The secondary endpoints were acute and late toxicities and the 24-month actuarial late toxicity-free survival. Objective response rate (ORR) included CR and partial response (PR). Clinical benefit (CB) included ORR and stable disease (SD). Toxicity was evaluated by the Radiation Therapy Oncology Group (RTOG) and the European Organization for Research and Treatment of Cancer (EORTC) and Common Terminology Criteria for Adverse Events (CTCAE) scales, according to center policy. Logistic and Cox regression were used for the uni- and multivariate analysis of factors predicting clinical CR and actuarial outcomes. RESULTS: CR, PR, and SD were observed in 291 (65.2%), 106 (23.8%), and 33 (7.4%) lesions, giving a rate of CB of 96.4%. Patient aged ≤60 years, planning target volume (PTV) ≤18 cm3 , lymph node disease, and biologically effective dose α/ß10 > 70 Gy were associated with higher chance of CR in the multivariate analysis. With a median follow-up of 22 months (range, 3-120), the 24-month actuarial LC rate was 81.9%. Achievement of CR and total dose >25 Gy were associated with better LC rate in the multivariate analysis. Mild toxicity was experienced in 54 (20.7%) patients; of 63 side effects, 48 were grade 1, and 15 were grade 2. The 24-month late toxicity-free survival rate was 95.1%. CONCLUSIONS: This study confirms the activity and safety of SBRT in patients with MPR-OC and identifies clinical and treatment parameters able to predict CR and LC rate. IMPLICATIONS FOR PRACTICE: This study aimed to define activity and safety of stereotactic body radiotherapy (SBRT) in a very large, real life data set of patients with metastatic, persistent, recurrent ovarian cancer (MPR-OC). Patient age <60 years, PTV <18 cm3 , lymph node disease, and biologically effective dose α/ß10 >70 Gy were associated with higher chance of complete response (CR). Achievement of CR and total dose >25 Gy were associated with better local control (LC) rate. Mild toxicity was experienced in 20.7% of patients. In conclusion, this study confirms the activity and safety of SBRT in MPR-OC patients and identifies clinical and treatment parameters able to predict CR and LC rate.

Repeated courses of radiation treatment in an HER2-positive breast cancer patient with diffuse brain metastases: A case report.

In human epidermal growth factor receptor 2 (HER2+) expressing breast cancer subtype, the incidence of brain metastases is common and patients often die due to uncontrolled cranial disease. This is a case report of a HER2+ breast cancer woman with diffuse brain metastases that experienced long survival and clinical benefit from multiple radiotherapy treatments and combined systemic therapy, without increased toxicity.

18F-choline PET/CT driven salvage radiotherapy in prostate cancer patients: up-date analysis with 5-year median follow-up.

PURPOSE: Salvage radiotherapy is generally considered as the standard treatment for biochemical relapse after surgery. Best results have been obtained with a PSA value < 0.5 ng/ml at relapse, while 60-66 Gy is deemed as standard total dose. Modern imaging, as dynamic-18F-choline PET/CT may identify site of recurrence, allowing dose escalation to a biological target volume. METHODS: Hundred and fifty patients showed a local relapse at dynamic-18F-choline PET/CT at time of biochemical recurrence. High-dose salvage radiotherapy was delivered up to total dose of 80 Gy to 18F-choline PET/CT positive area. Toxicity and relapse-free survival were recorded. RESULTS: Median PSA value at the beginning of salvage radiotherapy was 0.47 ng/ml (range 0.2-17.5 ng/ml). One-hundred and thirty nine patients (93%) completed salvage radiotherapy without interruptions. Acute gastrointestinal grade ≥ 2 toxicity was recorded in 13 patients (9%), acute genitourinary grade ≥ 2 toxicity in 2 patients (1.4%). One patient (0.7%) experienced late gastrointestinal grade 4 toxicity and 2 patients (1.4%) late acute genitourinary grade 3 toxicity. With a median follow-up of 63.5 months, 5 and 7-years relapse-free survival were 70% and 60.7%, respectively. CONCLUSION: With a median follow-up of 5 years the present study confirms that high-dose salvage radiotherapy to a biological target volume is feasible, with low rate of late toxicity and promising activity.

Radiotherapy and Vascular Endothelial Growth Factor Receptor-Tyrosine Kinase Inhibitors in Renal Cancer.

Treatment of metastatic renal cell carcinoma (mRCC) has seen substantial progress over the last decade. A number of targeted therapies have been shown to improve clinical outcome. Vascular endothelial growth factor receptor (VEGFR)-tyrosine kinase inhibitors (TKIs) are an effective option in treating mRCC. RCC is traditionally perceived to be a radioresistant malignancy with a limited role of radiotherapy (RT) in the management of localized disease. While RCC appears to be radioresistant using conventionally fractionated RT, preclinical data suggest increased radiosensitivity when an ablative, hypofractionated schedule is used. RT is a common treatment for metastases; therefore, it is important to understand how best to use the combination of RT with targeted therapies. Preclinical studies have suggested that the combination of anti-angiogenic drugs with RT enhances the therapeutic effect compared with ionizing radiation alone. However, clinical data gave rise to warnings due to an increased incidence of severe gastrointestinal side effects. This article reviews the literature behind the preclinical and clinical data of the combination of RT with VEGFR-TKIs currently approved for RCC (sunitinib, sorafenib, pazopanib, and axitinib), with a focus on dose schedules as well as efficacy and toxicity.

Efficacy of a Propolis-Based Syrup (FARINGEL) in Preventing Radiation-Induced Esophagitis in Locally Advanced Lung Cancer.

AIM: To evaluate the efficacy of a propolis-based syrup, FARINGEL®, in preventing radiation-induced esophagitis in locally advanced lung cancer patients. METHODS: Patients were treated with concurrent chemoradiotherapy (CRT) using involved-field radiotherapy (RT). Every patient received FARINGEL at the beginning of CRT until the first follow-up. The data of the study group were compared with the data of a control group treated without the administration of the syrup. RESULTS: Forty-five patients were enrolled. Forty-one (91.1%) completed the protocol and were evaluable for esophagitis. Grade ≥2 toxicity occurred in 9/41 patients (22%). No differences in overall toxicity were detected between the study group and the control group (n = 55, 60.9 vs. 54.5%; p = ns). Grade 2-3 esophagitis was lower in the study group in comparison with the control group (22 and 38%, respectively), but statistical significance was not reached (p = 0.09). However, the onset of grade ≥2 esophagitis was delayed in the study group compared to the control group, occurring at higher doses of RT (41.8 vs. 25.4 Gy; p < 0.001). Furthermore, the mean number of interruption days for esophagitis was lower in the study group than in the control group (0.6 ± 2.0 vs. 2.1 ± 3.6; p = 0.025). CONCLUSION: FARINGEL was well-tolerated and delayed esophagitis that was induced by CRT for locally advanced lung cancer.

Variability in axillary lymph node delineation for breast cancer radiotherapy in presence of guidelines on a multi-institutional platform.

AIM: To quantify the variability between radiation oncologists (ROs) when outlining axillary nodes in breast cancer. MATERIAL AND METHODS: For each participating center, three ROs with different levels of expertise, i.e., junior (J), senior (S) and expert (E), contoured axillary nodal levels (L1, L2, L3 and L4) on the CT images of three different patients (P) of an increasing degree of anatomical complexity (from P1 to P2 to P3), according to contouring guidelines. Consensus contours were generated using the simultaneous truth and performance level estimation (STAPLE) method. RESULTS: Fifteen centers and 42 ROs participated. Overall, the median Dice similarity coefficient was 0.66. Statistically significant differences were observed according to the level of expertise (better agreement for J and E, worse for S); the axillary level (better agreement for L1 and L4, worse for L3); the patient (better agreement for P1, worse for P3). Statistically significant differences in contouring were found in 18% of the inter-center comparison. Less than a half of the centers could claim to have a good agreement between the internal ROs. CONCLUSIONS: The overall intra-institute and inter-institute agreement was moderate. Central lymph-node levels were the most critical and variability increased as the complexity of the patient's anatomy increased. These findings might have an effect on the interpretation of results from multicenter and even mono-institute studies.

SBRT: A viable option for treating adrenal gland metastases.

The management strategy of adrenal metastases depends on different clinical situations. Adrenal metastasectomy in selected patients with isolated adrenal metastases is considered the treatment of choice, showing prolonged survival compared to chemotherapy alone. More recently, Stereotactic Body Radiation Therapy (SBRT) has emerged as an alternative local ablative treatment modality although limited data are available on the use of SBRT in treating adrenal gland metastases. Preliminary results are, however, encouraging, especially in selected patients with oligometastatic disease. We herewith review and discuss the potential role of SBRT as a local ablative treatment modality for adrenal metastases.

A clinical score, including biohumoral parameters, is a useful pretest index to discriminate pulmonary infections from radiation damage in chemoradiation-treated lung cancer patients.

To obtain an easy and prompt differential diagnosis between lower airways infections and acute radiation pneumonitis in chemoradiation lung cancer patients. From 303 patients treated, only patients with severe pulmonary symptoms were hospitalized. Clinical and radiation scores were calculated evaluating clinical, biohumoral, dosimetric parameters. Out of 36 patients hospitalized, infections and acute radiation pneumonitis were reported in 66.7% and 33.3%, respectively. Patients with clinical score ≥ 2 had an Odds Ratio of 3.4 (1.4-8.3; p = .006) to have infectious pneumonia, while radiation score was not predictive.

Radioprotective effect of calcium channel blockers against late rectal bleeding in prostate cancer.

OBJECTIVE: This study was done to assess the impact of clinical factors and in particular the use of drugs for concomitant illnesses on late radiation-induced rectal bleeding in patients with prostate cancer. MATERIALS AND METHODS: Patients with histologically proven prostate adenocarcinoma treated with radical radiotherapy and followed up for at least 6 months were selected. The correlation between late rectal bleeding and a number of factors was investigated by univariate and multivariate analysis. RESULTS: A total of 278 patients who underwent radiotherapy at our institution between October 2002 and May 2011 were selected. At univariate analysis, delivery of radiation doses higher than 70 Gy and use of angiotensin-converting enzyme inhibitors were associated with a higher incidence of rectal bleeding. Conversely, patients who used calcium channel blockers had a lower risk (3-year rectal bleeding-free survival 89.8 versus 66.5 %, p = 0.043). At multivariate analysis, use of calcium channel blockers was found to have a protective effect with a hazard ratio of 0.3 (95 % CI 0.12-0.96). Delivery of higher radiation doses was associated with an increased risk of rectal bleeding (hazard ratio 3.02, 95 % CI 1.23-7.38). CONCLUSIONS: Use of calcium channel blockers during and after radiotherapy treatment might have a protective effect against late rectal bleeding. If these results are reconfirmed by larger clinical series, calcium channel blockers may be tested as radioprotector agents in clinical trials.

Machine-learning prediction of treatment response to stereotactic body radiation therapy in oligometastatic gynecological cancer: A multi-institutional study.

BACKGROUND AND PURPOSE: We aimed to develop and validate different machine-learning (ML) prediction models for the complete response of oligometastatic gynecological cancer after SBRT. MATERIAL AND METHODS: One hundred fifty-seven patients with 272 lesions from 14 different institutions and treated with SBRT with radical intent were included. Thirteen datasets including 222 lesions were combined for model training and internal validation purposes, with an 80:20 ratio. The external testing dataset was selected as the fourteenth Institution with 50 lesions. Lesions that achieved complete response (CR) were defined as responders. Prognostic clinical and dosimetric variables were selected using the LASSO algorithm. Six supervised ML models, including logistic regression (LR), classification and regression tree analysis (CART) and support vector machine (SVM) using four different kernels, were trained and tested to predict the complete response of uterine lesions after SBRT. The performance of models was assessed by receiver operating characteristic curves (ROC), area under the curve (AUC) and calibration curves. An explainable approach based on SHapley Additive exPlanations (SHAP) method was deployed to generate individual explanations of the model's decisions. RESULTS: 63.6% of lesions had a complete response and were used as ground truth for the supervised models. LASSO strongly associated complete response with three variables, namely the lesion volume (PTV), the type of lesions (lymph-nodal versus parenchymal), and the biological effective dose (BED10), that were used as input for ML modeling. In the training set, the AUCs for complete response were 0.751 (95% CI: 0.716-0.786), 0.766 (95% CI: 0.729-0.802) and 0.800 (95% CI: 0.742-0.857) for the LR, CART and SVM with a radial basis function kernel, respectively. These models achieve AUC values of 0.727 (95% CI: 0.669-0.795), 0.734 (95% CI: 0.649-0.815) and 0.771 (95% CI: 0.717-0.824) in the external testing set, demonstrating excellent generalizability. CONCLUSION: ML models enable a reliable prediction of the treatment response of oligometastatic lesions receiving SBRT. This approach may assist radiation oncologists to tailor more individualized treatment plans for oligometastatic patients.

Stereotactic Ablative Radiation Therapy for Oligometastatic Ovarian Cancer Lymph Node Disease: The MITO-RT3/RAD Phase II Trial.

PURPOSE: MITO-RT3/RAD (NCT04593381) is a prospective multicenter phase 2 trial designed to assess the effectiveness and safety of stereotactic body radiation therapy (SBRT) in patients who received diagnoses of oligometastatic ovarian cancer. In this report, we provide the results of the trial in the setting of lymph node disease. METHODS AND MATERIALS: The primary endpoint was the complete response (CR) rate, secondary endpoints included local control (LC), progression-free survival (PFS), overall survival, treatment-free interval, and toxicity rates. The sample size was based on a previous study reporting an average 70.0% CR with SBRT. The study was powered to detect an improvement in the CR rate from 70.0% to 85.0%, with an α error of 0.05 (one-side) and a ß error of 0.1. RESULTS: The study met its primary endpoint of a statistically significant improvement in CR. One hundred thirty-five patients with 249 lesions were enrolled across 15 institutions from May 2019 to November 2023. CRs were observed in 194 lesions (77.9%), partial responses in 40 (16.1%), stable disease in 14 (5.6%), and progressive disease in 1 lesion (0.4%). The objective response rate was 94%, with an overall clinical benefit rate of 99.6%. CR lesions exhibited a significantly higher LC rate than partial or not responding lesions (12-month LC: 92.7% vs 63.1%, P < .001). The 12-month actuarial rates for PFS and for overall survival were 36.6% (CR, 38.3% vs not-CR, 18.8%; P, .022) and 97.2% (CR, 97.8% vs not-CR, 93.8%; P, .067), respectively. The 12-month actuarial rate for treatment-free interval was 52.7% (CR, 58.4% vs not-CR, 24.4%; P, .004). CR was substantially associated with higher PFS (P, .036) and treatment-free interval (P, .006) rates in the univariate analysis. Twenty-three patients (17.0%) experienced mild acute toxicity. Late toxicity was reported in 9 patients (6.7%), mostly grade 1. CONCLUSIONS: This trial confirms the efficacy of ablative SBRT, with minimal toxicity observed. SBRT offered a high CR rate, promising long-term outcomes, and a significant systemic therapy-free survival period for complete responders.

Long-term analysis of gemcitabine-based chemoradiation after surgical resection for pancreatic adenocarcinoma.

PURPOSE: To evaluate the efficacy in terms of local control (LC) of 24 h infusion of gemcitabine plus radiotherapy after surgery for pancreatic cancer. METHODS: Weekly gemcitabine (100 mg/m(2)) was provided as a 24-hour infusion during the course of radiotherapy (50.4 Gy to the tumor, 39.6 Gy to the nodes). Patients subsequently received five cycles of gemcitabine monochemotherapy (1,000 mg/m(2) 1, 8, q21). The primary end point of the study was to achieve a 2-year LC rate of ≥80 % with type I and II errors of 5 and 20 %. The study was designed to accrue a maximum sample size of 35 patients. Secondary end points were toxicity evaluation, metastasis-free survival (MFS), and overall survival (OS). RESULTS: Data of 35 patients were available. Most of the patients (n = 27; 77.1 %) had duodeno-cephalo-pancreatectomy, 5 (14.3 %) distal pancreatectomy, and 3 (8.6 %) total pancreatectomy. The pathological stages were T1-T2 (n = 7; 20.0 %), T3-T4 (n = 28; 80.0 %), N0 (n = 17; 48.6 %), and N1 (n = 18; 51.4 %). Thirty patients (85.7 %) completed chemoradiation. Twenty-three patients (65.7 %) received further sequential chemotherapy. Acute toxicity was acceptable. No late toxicity occurred. The median follow-up period was 64 (range 24-118) months, and 2-year crude rate of LC was 83 (median not reached). Median MFS and OS were 26.5 and 22.5 months, respectively. CONCLUSIONS: The rate of LC met the main goal of the study. The regimen resulted in a high LC rate but failed to show a benefit in terms of OS or MFS, thus suggesting the need for a more intensified multimodal approach.

Preventing Cardiotoxicity in Personalized Breast Irradiation.

BACKGROUND: This study aims to assess the benefit of a deep inspiration breath hold (DIBH) over the standard irradiation technique, and eventually to identify anatomical and/or treatment preplanning characteristics correlated with the LAD dose. METHODS: Patients with left-sided breast cancer undergoing whole breast radiotherapy with DIBH were analyzed. All patients included in the analysis had plans in DIBH and free-breathing (FB). Receiving operating characteristics (ROC analysis) were used to identify the cut-off point of parameters to predict the LAD maximum dose > 10 Gy and LAD mean dose > 4 Gy, and the areas under the curve (AUCs) were computed. Post-test probability has been performed to evaluate the effect of parameters' combination. RESULTS: One hundred ninety-seven patients were analyzed. The LAD dose was significantly reduced in DIBH plans with the maximum and mean dose reduced by 31.7% (mean value 3.5 Gy vs. 4.8 Gy, p ≤ 0.001) and 28.1% (mean value 8.2 Gy vs. 12.8 Gy, p ≤ 0.001) in DIBH plans compared to FB plans. The strongest predictor of the LAD dose (maximum > 10 Gy and mean > 4 Gy) was the minimum distance of LAD from tangent open fields. Other parameters were lung volume and heart volume (LAD Dmax > 10 Gy) and lung volume, heart volume, and breast separation (LAD Dmean > 4 Gy). CONCLUSION: The dosimetric advantage of DIBH is clear in all patients and DIBH should always be preferred.