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• A single MC photon model was made using RayStation for three identical LINACs. • The accuracy of the model was assessed in homogeneous and heterogeneous medium. • The ideal MC model was compared with a clinical CC and an un-optimized MC model. A photon Monte Carlo (MC) model was commissioned for flattened (FF) and flattening filter free (FFF) 6 MV beam energy. The accuracy of this model, as a single model to be used for three beam matched LINACs, was evaluated. Multiple models were created in RayStation v.10A for three linacs equipped with Elekta "Agility" collimator. A clinically commissioned collapsed cone (CC) algorithm (GoldCC), a MC model automatically created from the CC algorithm without further optimization (CCtoMC) and an optimized MC model (GoldMC) were compared with measurements. The validation of the model was performed by following the recommendations of IAEA TRS 430 and comprised of basic validation in a water tank, validation in a heterogeneous phantom and validation of complex IMRT/VMAT paradigms using gamma analysis of calculated and measured dose maps in a 2D-Array. Dose calculation with the GoldMC model resulted in a confidence level of 3% for point measurements in water tank and heterogeneous phantom for measurements performed in all three linacs. The same confidence level resulted for GoldCC model. Dose maps presented an agreement for all models on par to each other with γ criteria 2%/2mm. The GoldMC model showed a good agreement with measured data and is determined to be accurate for clinical use for all three linacs in this study. [ABSTRACT FROM AUTHOR]

Nivolumab showed an overall survival (OS) benefit in pretreated metastatic renal cell carcinoma (mRCC). The role of stereotactic body radiotherapy (SBRT) in mRCC remains to be defined. Our aim was to evaluate the efficacy and safety of SBRT in combination with nivolumab in second- and third-line mRCC patients. The NIVES study was a phase II, single-arm, multicenter trial in patients with mRCC with measurable metastatic sites who progressed after antiangiogenic therapy, of whom at least one was suitable for SBRT. The patients received SBRT to a lesion at a dose of 10 Gy in three fractions for 7 d from the first infusion of nivolumab. Nivolumab was given at an initial dose of 240 mg every 14 d for 6 mo and then 480 mg q4-weekly in responding patients. We hypothesized that nivolumab plus SBRT improves the objective response rate (ORR) compared with nivolumab alone from 25% (derived from historical controls) to 40%. Secondary endpoints were progression-free survival (PFS), OS, disease control rate (DCR) of irradiated and nonirradiated metastases, and safety. Sixty-nine patients were enrolled from July 2017 to March 2019. The ORR was 17% and the DCR was 55%. The median PFS was 5.6 mo (95% confidence interval [CI], 2.9–7.1) and median OS 20 mo (95% CI, 17–not reached). After 1.5 yr of follow-up, 23 patients died. The median time to treatment response was 2.8 mo and median duration of response was 14 mo. No new safety concerns arose. We did not find sufficient evidence to suggest that nivolumab in combination with SBRT provides an added benefit in pretreated mRCC patients; it should however be evaluated in patients with oligometastatic or oligoprogressive disease. Nivolumab in combination with stereotactic body radiotherapy does not provide evidence of increased outcomes in metastatic renal cell carcinoma patients. However this approach was safe and showed a good response of the irradiated lesions. Nivolumab in combination with stereotactic body radiotherapy does not provide evidence of an added benefit in patients with pretreated metastatic renal cell carcinoma; however, it should be evaluated in patients with oligometastic or oligoprogressive disease. This approach was safe and showed a faster time to treatment response, median duration of response, and good response of the irradiated lesions. [ABSTRACT FROM AUTHOR]

Italy experienced one of the world's deadliest COVID-19 outbreaks and healthcare systems had to instantly reorganise activity. The Italian Radiation Oncology Departments adapted numerous solutions to minimize the disruptions. Information technologies, treatment prioritization and implementation of hypofractionation and protection procedures allowed balancing between cancer patient care and patient/healthcare workers safety. [ABSTRACT FROM AUTHOR]

Stereotactic body radiotherapy (SBRT) and elective nodal radiotherapy (ENRT) are being investigated as metastasis-directed treatments in oligorecurrent prostate cancer (PC); however, comparative data are still lacking. To compare outcome and toxicity between both treatments. Primary endpoint was metastasis-free survival, adjusted for selected variables (aMFS). This was a multi-institutional, retrospective analysis of 506 (SBRT: 309, ENRT: 197) patients with hormone-sensitive nodal oligorecurrent PC (five or fewer lymph nodes (LNs; N1/M1a), treated between 2004 and 2017. Median follow-up was 36 mo (interquartile range 23–56). SBRT was defined as a minimum of 5 Gy per fraction to each lesion with a maximum of 10 fractions. ENRT was defined as a minimum dose of 45 Gy in up to 25 fractions to the elective nodes, with or without a simultaneous boost to the suspicious node(s). The choice of radiotherapy (RT) was at the discretion of the treating physician, with treatments being unbalanced over the centers. In total, 506 patients from 15 different treatment centers were included. Primary treatment was radical prostatectomy, RT, or their combination. Nodal recurrences were detected by positron emission tomography/computer tomography (97%) or conventional imaging (3%). Descriptive statistics was used to summarize patient characteristics. ENRT was associated with fewer nodal recurrences compared with SBRT (p < 0.001). In a multivariable analysis, patients with one LN at recurrence had longer aMFS after ENRT (hazard ratio: 0.50, 95% confidence interval 0.30–0.85, p = 0.009). Late toxicity was higher after ENRT compared with that after SBRT (16% vs. 5%, p < 0.01). Limitations include higher use of hormone therapy in the ENRT cohort and nonstandardized follow-up. ENRT reduces the number of nodal recurrences as compared with SBRT, however at higher toxicity. Our findings hypothesize that ENRT should be preferred to SBRT in the treatment of nodal oligorecurrences. This hypothesis needs to be evaluated in a randomized trial. This study investigated the difference between stereotactic and elective nodal radiotherapy in treating limited nodal metastatic prostate cancer. Nodal relapse was less frequent following elective nodal radiotherapy than following stereotactic body radiotherapy, and thus elective nodal radiotherapy might be the preferred treatment. In treating nodal oligorecurrent prostate cancer, elective nodal radiotherapy reduces nodal relapse compared with stereotactic body radiotherapy. However, elective nodal radiotherapy was associated with higher toxicity. [ABSTRACT FROM AUTHOR]

Parotid gland (PG) shrinkage and neck volume reduction during radiotherapy of head and neck (H&N) cancer patients is a clinical issue that has prompted interest in adaptive radiotherapy (ART). This study focuses on the difference between planned dose and delivered dose and the possible effects of an efficient replanning strategy during the course of treatment. Six patients with H&N cancer treated by tomotherapy were retrospectively enrolled. Thirty daily dose distributions (D MVCT) were calculated on pretreatment megavoltage computed tomography (MVCT) scans. Deformable Image Registration which matched daily MVCT with treatment planning kilovoltage computed tomography was performed. Using the resulting deformation vector field, all daily D MVCT were deformed to the planning kilovoltage computed tomography and resulting doses were accumulated voxel per voxel. Cumulative D MVCT was compared to planned dose distribution performing γ-analysis (2 mm, 2% of 2.2 Gy). Two single-intervention ART strategies were executed on the 18th fraction whose previous data had suggested to be a suitable timepoint for a single replanning intervention: (1) replanning on the original target and deformed organ at risks (OARs) (a "safer" approach regarding tumor coverage) and (2) replanning on both deformed target and deformed OARs. D MVCT showed differences between planned and delivered doses (3D-γ 2mm/2%-passing rate = 85 ± 1%, p < 0.001). Voxel by voxel dose accumulation showed an increase in average dose of warped PG of 3.0 Gy ± 3.3 Gy. With ART the average dose of warped PG decreased by 3.2 Gy ± 1.7 Gy in comparison to delivered dose without replanning when both target and OARs were deformed. Average dose of warped PG decreased by 2.0 Gy ± 1.4 Gy when only OARs were deformed. Anatomical variations lead to increased doses to PGs. Efficient single-intervention ART-strategies with replanning on the 18th MVCT result a reduced PG dose. A strategy with deformation of both target and OAR resulted in the lowest PG dose, while formally maintaining PTV coverage. Deformation of only OAR nevertheless reduces PG dose and has less uncertainties regarding PTV coverage. [ABSTRACT FROM AUTHOR]

• Italy has been slowly reopening after a 10 week lockdown following COVID-19 outbreak. • A survey was administered to Italian RT departments to depict the current scenario. • In P1, RT departments managed to contain contagion with modest workload reduction. • All safety measures, maintained in P2, allowed RT departments to restore activities. • Reorganization of activities will be crucial to prevent the second wave of pandemic. [ABSTRACT FROM AUTHOR]

Abstract: Background and purpose: Post-operative radiotherapy (PORT) in radically resected non-small cell lung cancer (NSCLC) has the aim to reduce loco regional recurrence and to improve overall survival. PORT has been evaluated in several trials but indication to post-operative treatment in N2 patients is still debated. Material and methods: We retrospectively analyzed 175 patients treated at University of Florence between 1988 and 2004 with completely resected NSCLC stages IIIA–IIIB, N2 disease. Surgery consisted in a lobectomy in 58.9% and in a bi-lobectomy or in a pneumonectomy in 41.1% of patients. One hundred and nineteen patients underwent PORT and 56 patients did not receive PORT (no-PORT). Results: At a median follow-up of 27.6months (range 4–233months), we found a significant reduction in local recurrence (LR) in PORT group (log-rank test p =0.015; HR: 0.45; 95%CI: 0.24–0.87). No statistical difference were found in terms of overall survival (OS) (log-rank test p =0.92). Concerning other prognostic factors, male sex emerged as statistically significant (HR:4.33;1.04–18.02) on local progression free survival (LPFS) at univariate analysis. Acute and long-term toxicity was mild. Conclusion: Our retrospective analysis showed that PORT may improve local disease control in N2 NSCLC patients with an acceptable treatment-related toxicity. [Copyright &y& Elsevier]

Abstract: Objectives: To review the treatment, toxicity, and outcomes in patients with Stage II seminoma after orchidectomy. Materials and methods: A retrospective chart review of all patients with Stage II seminoma referred for initial treatment, from 1965 to 2005, was performed. Treatment approaches, toxicity, and outcomes were analyzed. Results: A total of 106 patients (83 with Stage IIA, 19 with Stage IIB, and 4 with Stage IIC) were seen between 1965 and 2005. Median age at diagnosis was 36 years (range: 19–71). Median follow-up was 21 years (range: 1.2–42). Eighty-nine patients were treated with adjuvant radiotherapy alone; 13 patients received a combined treatment modality with chemotherapy and radiotherapy after orchidectomy, 4 patients were treated with chemotherapy alone. Generally the treatment was well tolerated, with the main toxicity occurring in patients treated with extended-field radiotherapy. The 5-year disease-specific survival was 96% for the entire group. The 5-year relapse-free survivals for Stages IIA, IIB, and IIC disease were 94%, 72.5%, and 75%, respectively. Fifteen patients developed a relapse and were managed by chemotherapy; 5 of them achieved complete remission and remain free from further recurrence at last follow-up, while 10 died of the disease. Second malignancies were diagnosed in 4 (3.7%) patients during the follow-up. Conclusions: In Stage IIA seminoma, radiotherapy continues to provide excellent results, as the majority of patients will be cured with this treatment alone. Radiotherapy or chemotherapy should be offered as an alternative to Stage IIB patients. Chemotherapy remains the treatment of choice for Stage IIC seminoma. [Copyright &y& Elsevier]

Purpose: To analyze the relationship between a delay in radiotherapy (RT) after breast-conserving surgery and ipsilateral breast recurrence (BR). Methods and Materials: We included in our analysis 4,820 breast cancer patients who had undergone postoperative RT at the University of Florence. The patients were categorized into four groups according to the interval between surgery and RT (T1, <60 days; T2, 61–120 days; T3, 121–180 days; and T4, >180 days). Results: On multivariate analysis, the timing of RT did not reach statistical significance in patients who received only postoperative RT (n = 1,935) or RT and hormonal therapy (HT) (n = 1,684) or RT, chemotherapy (CHT), and HT (n = 529). In the postoperative RT-only group, age at presentation, surgical margin status, and a boost to the tumor bed were independent prognostic factors for BR. In the RT plus HT group, age at presentation and boost emerged as independent prognostic factors for BR (p = 0.006 and p = 0.049, respectively). Finally, in the RT, CHT, and HT group, only multifocality was an independent BR predictor (p = 0.01). Only in the group of patients treated with RT and CHT (n = 672) did multivariate analysis with stepwise selection show RT timing as an independent prognostic factor (hazard ratio, 1.59; 95% confidence interval, 1.01–2.52; p = 0.045). Analyzing this group of patients, we found that most patients included had worse prognostic factors and had received CHT consisting of cyclophosphamide, methotrexate, and 5-fluorouracil before undergoing RT. Conclusion: The results of our study have shown that the timing of RT itself does not affect local recurrence, which is mainly related to prognostic factors. Thus, the “waiting list” should be thought of as a “programming list,” with patients scheduled for RT according to their prognostic factors. [Copyright &y& Elsevier]