Saving lives, saving earth: hypofractionation and carbon footprint.

PURPOSE: The healthcare system contributes approximately 5% of global greenhouse gas emissions, yet the environmental impact of radiotherapy treatments remains inadequately assessed. MATERIAL AND METHODS: We selected all breast cancer patients (1959 patients) treated with adjuvant radiotherapy between 2015 and 2023 in one institution. We analyzed the CO2 emissions associated with travel. We also selected 60 patients randomly to analyze treatment-associated carbon emissions. We compared three different fractionation schemes: normofractionation (25-30 fractions, fx), hypofractionation (15-18fx), and ultra-hypofractionation (5-6fx). RESULTS: Our study revealed a significant reduction in carbon emissions within the 5-fractions group compared to the 15-fractions group (26.69kg vs 57.13kg, p < 0.001), saving approximately the CO2 emissions associated with the electricity consumption of an average Spanish household for 12 days, or the emissions of a passenger flying from Madrid to Barcelona. CONCLUSION: Most of the carbon footprint of radiotherapy is due to travel. Hypofractionation could be an appropriate solution to protect the environment.

Reirradiation salvage radiotherapy for recurrent prostate cancer after primary low-dose brachytherapy.

PURPOSE: Local recurrence of prostate cancer after low-dose rate brachytherapy is a clinical problem with limited salvage treatment options. This prospective study evaluated the tolerability and outcome of salvage external beam radiation therapy (S-EBRT) for locally recurrent prostate cancer after primary low-dose rate prostate brachytherapy (LDR-BT). MATERIALS AND METHODS: Between October 2012 and 2022, 18 patients with biopsy-proven locally recurrent prostate cancer after primary LDR-BT and received S-EBRT. We evaluated biochemical failure (BF), overall survival (OS) and acute/late gastrointestinal and urinary toxicities (CTCAE v5.0 or CTCAE v4, only before 2017). RESULTS: Median follow-up was 32 months (range, 5-124). The median age was at S-EBRT 68 years (range 59-79). 34% (6/18) were low risk, 44% (8/18) intermediate risk, 5% (1/18) high risk, and 17% (3/18) not specified. All patients were treated with IMRT/VMAT and received 60 Gy (2.5 Gy/fraction) to the prostate and 40% (7/18) 55.2 Gy (2,3 Gy/fx) to the seminal vesicles. 56% received ADT The 3-year OS and biochemical relapse-free survival after S-EBRT were 100% and 89%, respectively, with a median PSA nadir 0,035 ng/mL (0,01-0,34). Acute cystitis was present in 72% (13/18) of patients (27% of Grade > 2). Urethritis was present in 78% (14/18) patients (16% of cases Grade > 3), and acute rectitis occurred in 22% (4/18) of patients (no cases Grade > 3). CONCLUSIONS: Our data suggest that the treatment of locally recurrent prostate cancer with S-EBRT could provide adequate disease control safely and be used as an additional treatment in the natural history of prostate cancer patients. However, the results are still early and the sample is small; larger studies with longer follow-up would be mandatory.

Haematological and renal toxicity of radiation therapy in neuroblastoma paediatric patients.

PURPOSE: The objective of this study was to evaluate the renal and hematologic toxicity in paediatric patients with adrenal high-risk neuroblastoma who have received radiation therapy (RT) as part of radical treatment. MATERIAL AND METHODS: Pediatric patients diagnosed with high-risk adrenal neuroblastoma who received RT as part of the definitive treatment between January 2004 and May 2020 in a single institution were selected. Complete blood counts (CBC) and creatinine clearance (CrCl) pre-RT and post-RT were compared through the Wilcoxon signed-rank test and correlated with survival analysis by Cox regression. RESULTS: Forty-two children with a median age of 3 years at diagnosis and 2.8 years of follow-up were selected. A significant and acute decrease in lymphocytes was found (p = 0.002) 1 month from RT. Patients with a drop higher than 50% of the previous value experimented a significant reduction in overall survival (55 vs 10%; p = 0.031). At the end of the follow-up, a significant increase in all blood counts was observed. With respect to renal function, an acute and significant decrease in CrCl was observed tin patients younger than 4 years who received RT (p = 0.013). However, it was not clinically relevant. CONCLUSION: Our data suggest that acute lymphopenia occurs after RT and could be associated with a poorer prognosis. Other blood counts are reduced after RT and all of them are in physiological range at the end of follow-up. Our cohort presented excellent renal outcomes without any case of chronic renal dysfunction.