Purpose: The purpose of the study was to evaluate the dosimetric impact of sexual-sparing radiotherapy for prostate cancer, with magnetic resonance-only treatment planning.
Material and methods: Fifteen consecutive patients receiving prostate cancer radiotherapy were selected. A synthetic CT was generated with a deep learning method from each T2-weighted MRI performed at the time of treatment planning. For each patient, two plans were performed: standard treatment planning and sexual-structures sparing treatment planning. The treatment plan was designed to deliver a dose of 78Gy to the prostate and 50Gy to the seminal vesicles in 2Gy daily fractions, using volumetric arc therapy. Dose-volume histograms were computed to compare treatment plans.
Results: All plans fulfilled dosimetric objectives and were equivalent regarding planning target volume coverage. The doses delivered to both rectum, bladder, and femoral heads were similar between plans (P=0.20). Sexual-sparing plans enabled to decrease all dosimetric parameters on sexual organs-at-risk. The mean penile bulb dose in sexual-sparing plans was significantly reduced (21.1Gy±20.7 versus 13.4Gy±14.0, P<0.01), however with large variability observed between individuals. The mean dose delivered to the corpora cavernosa was also significantly reduced within sexual-sparing plans (13.1Gy±16.7 versus 8.6Gy±10.4, P<0.01). A significant reduction was also observed in the highest doses delivered to internal pudendal arteries (D10%: 48.4Gy±8.3 versus 33.1Gy±4.6, P<0.05; D5%: 52.0Gy±8.7 versus 36.8Gy±5.5, P<0.05).
Conclusion: Sparing of sexual structures appears feasible, without compromising neither planning target volume coverage nor doses delivered to non-sexual organs at risk. The clinical significance of this dose-reduction requires prospective evaluation.
Purpose: This retrospective study was conducted to ensure that irradiation of the pelvic lymph node areas associated with simultaneous hypofractionated boost to the prostate according to the protocol implemented at the university hospital of Tours (France) does not result in excess urinary and digestive toxicity in the short and medium term.
Materials and methods: The study population included patients with localized unfavourable intermediate or high-risk prostate cancer. The dose delivered was 65Gy in 25 fractions of 2.6Gy to the prostate and seminal vesicles, and 50Gy in 25 fractions of 2Gy to the pelvic lymph nodes. Acute toxicity events (between the start of radiotherapy and the first follow-up consultation) and medium-term toxicity events (after the first follow-up consultation) were assessed using the CTCAE version 5.0 classification.
Results: Sixty-three patients were treated according to the protocol between January 1st, 2020, and October 31st, 2022. The majority of them had high-risk prostate cancer (79%). The median follow-up was 15 months. Very few patients reported grade 3-4 toxicity acutely (6% urinary and 0% digestive toxicity) or in the medium term (7% urinary and 0% and digestive toxicity).
Conclusion: Radiotherapy of pelvic lymph node areas with simultaneous hypofractionated boost to the prostate is feasible, with low rates of severe acute and medium-term toxicity.
Purpose: With the promising results of immunotherapy in patients with stage III melanoma, the role of adjuvant radiotherapy after resection and complete lymph-node dissection must be reassessed. We evaluate the outcomes and safety of adjuvant radiotherapy and immunotherapy compared to immunotherapy only in patients with resected stage III melanoma.
Patients and methods: This retrospective and single institution study included patients treated for a stage III melanoma with complete lymph-node dissection and adjuvant immunotherapy from January 2019 to December 2022. The radiotherapy associated with immunotherapy group was defined by completion of immunotherapy and adjuvant radiotherapy in the lymph-node dissection area. The primary endpoint was disease-free survival. The secondary endpoints were locoregional progression, incidence of adverse events grade 3 or above and disease-free survival rate in patients with high risk of locoregional recurrence.
Results: Thirty-three patients were included. Among them, twelve received adjuvant lymph-node field radiotherapy. The median duration of follow-up was 17months (range: 8-45months). Patients receiving radiotherapy and immunotherapy had a significantly higher disease stage and more frequent extracapsular extension. At 12months, the disease-free survival rate was 66.7% for the patients receiving immunotherapy alone (95% CI: 42.5-82.5%) and 83.3% for those receiving radiotherapy and immunotherapy (95% CI: 48.2-95.6%; P=0.131). The locoregional progression rate was 24% in patients receiving immunotherapy and 8% in patients receiving immunotherapy and radiotherapy (P=0.379). After adjuvant treatment, 6% of patients developed grade 3 or above immunotherapy-related events and none developed grade 3 or above radiation-related adverse events.
Conclusion: In patients with stage III melanoma, adjuvant lymph-node field radiotherapy combined with immunotherapy seems to be associated with longer disease-free survival, with acceptable tolerance. However, these results need to be confirmed by long-term and prospective studies.
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：