ESTRO 2025 - Abstract Book

S1283

Clinical – Lower GI

ESTRO 2025

The study population consisted of 80 patients (66% men, 34% women) with a mean age of 63 (28−78) years. Pre treatment rectal MRI showed ≥cT3 staging in 79 (98.8%), lymphnode positivity in 63 (78.8%), MRF+ in 49 (61.3%), and EMVI+ in 20 (25%) patients. Diverting stomas were created in 26.25% of patients before initiating TNT. TNT was started with ChT in 12.5% and with RT in 87.5%. SC-RT was performed in 41 (51.3%) and LC-ChRT in 39 (48.75%) patients. Side effects during RT were reported by 61% of patients. Due to side effects associated with capecitabine, 3.7% of patients received FOLFOX. Surgery after TNT was not performed in 4 cases, and in 5 cases exploratory laparotomy as performed due to inoperable tumors. The proportion of rectal resections/extirpations did not differ between the SC-TNT and LC-TNT groups. Pathological complete response (pCR) was detected in 15 cases (23%). No significant differences were observed between SC-TNT and LC-TNT groups in terms of pCR (p=0.878) and TRG (p=0.977). The R0 resection rate was higher in the LC-TNT group (p=0.042). At the current follow-up time (31.62 months), no significant differences were observed in rates of local recurrence (p=0.231), distant metastasis-free survival (p=0.380), or disease-free survival (p=0.177), although a trend favoring the LC-TNT group was noted. Conclusion: TNT can be safely and effectively implemented in everyday clinical practice without compromising surgical outcomes. Increasing evidence suggests that TNT can be considered the standard treatment for high-risk LARC. While our data show no significant differences in pCR or TRG between SC-TNT and LC-TNT, LC-TNT demonstrated higher R0 resection rate. With longer follow-up, further advantages of LC-TNT may emerge. References: Paolo Goffredo et al. Total Neoadjuvant Therapy versus Standard Neoadjuvant Chemoradiation in Patients with Locally Advanced Rectal Cancer: A Comparison of Short- and Long-term Oncologic Outcomes, Annals of Surgery 2021 August 4 Joseph C Kong et al. Reply to: Does Total Neoadjuvant Treatment Improve Overall Survival in Rectal Cancer? No, It Does Not, Annals of Surgical Oncology 2021 July 17 Anup Kasi et al. otal Neoadjuvant Therapy vs Standard Therapy in Locally Advanced Rectal Cancer: A Systematic Review and Meta-analysis, JAMA Network Open 2020 December 1, 3 (12): e2030097 Fausto Petrelli et al. Total Neoadjuvant Therapy in Rectal Cancer: A Systematic Review and Meta analysis of Treatment Outcomes, Annals of Surgery 2020, 271 (3): 44-48 Keywords: total neoadjuvant therapy

4499

Digital Poster Bowel Function and Bother After Radiation Therapy in Prostate Cancer Patients: Insights from a Prospective Study FATIMA ZAHRA CHRAA, amina majdi, chadia ezzouitina, karima nouni, amine lachgar, hanane el kacemi, tayeb kebdani, khalid hassouni radiotherapy, institut national d'oncologie, rabat, Morocco Purpose/Objective: Prostate cancer treatments, including radiation therapy (RT), can significantly impact patients' health-related quality of life (QoL). This study aimed to evaluate trajectories of QoL outcomes related to bowel function (BF) and bowel bother (BB) in prostate cancer patients treated with RT, with or without androgen deprivation therapy (ADT).

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