ESTRO 2024 - Abstract Book

S1485

Clinical - Lower GI

ESTRO 2024

Figure

2.

Frequencies

of

the

most

relevant

adverse

events

in

the

STD

arm.

Conclusion:

IMRT/VMAT was not associated with less acute preoperative toxicity compared with 3D-CRT in LARC treated with chemoradiotherapy or TNT in the prospective RAPIDO trial. In the TNT arm, nausea/ vomiting and fatigue (especially grade 1 and 2) occurred significantly more often in the IMRT/VMAT group. Chemotherapy compliance in the TNT arm was similar between patients treated with IMRT/VMAT or 3D-CRT.

Keywords: Technique, toxicity, RAPIDO

450

Poster Discussion

Lateral pelvic lymph nodal boost in locally advanced rectal cancer: A matched pair analysis

Rasika Sangle 1 , Reena Engineer 1 , Avinash Saklani 2 , Rahul Krishnatry 1 , Shivkumar Gudi 1 , Prashant Nayak 1 , Mufaddal Kazi 2 , Akshay Baheti 3 , Suman Ankathi 3 , Ashwin Desouza 2 1 Tata Memorial Hospital, Radiation Oncology, Mumbai, India. 2 Tata Memorial Hospital, Surgical Oncology, Mumbai, India. 3 Tata Memorial Hospital, Radiodiagnosis, Mumbai, India

Purpose/Objective:

A lateral pelvic lymph node (LPLN) is detected in 10% to 25% of individuals with locally advanced rectal cancer (LARC) upon presentation. LPLN includes obturator, Internal iliac, external iliac lymph nodes. These patients are known to have a worse prognosis overall and a higher probability of locoregional recurrence. However, there is no consensus on how to manage LPLN in the ideal manner. Neoadjuvant chemoradiation (NACTRT) followed by total mesorectal excision (TME) has emerged as the standard initial modality for treating LARC, especially in the West. (1) On the other hand, the Japanese have adopted upfront lateral pelvic lymph node dissection (LPLND) along with TME for all LARC patients. Even in experienced hands, LPLND is known to result in higher surgical