Contemporary neoadjuvant strategies for rectal cancer: The GRECCAR snapshot study.

Abstract

Neoadjuvant treatment for rectal cancer has evolved markedly with the growing adoption of total neoadjuvant therapy (TNT), organ-preservation strategies and selective omission of radiotherapy. Recent trials support risk-based personalization, but its application in real-world settings remains poorly documented. The aim was to describe current neoadjuvant treatment practices for mid-low rectal cancer in French expert centres and identify tumour- and patient-related factors influencing decisions. This observational study included patients with non-metastatic rectal adenocarcinoma ≤10 cm from the anal verge, discussed in tumour boards (October 2022 to March 2023) across GRECCAR centres. Tumours were classified as early, intermediate-risk or locally advanced rectal cancer (LARC). Neoadjuvant treatments were analysed according to tumour extension, location and age. Among 463 patients from 27 centres, the most frequent regimen was induction chemotherapy, mainly FOLFIRINOX, followed by long-course chemoradiotherapy (CRT) (65%). This approach was used in 51%, 66% and 71% of patients in the early, intermediate-risk and LARC groups, respectively (p = 0.0060). TNT was more frequently administered for low- than mid-rectal cancers, especially in LARC (86% vs. 71%, p = 0.016). In patients >75 years, CRT + consolidation chemotherapy and radiotherapy alone were proportionally more frequent. Among the early rectal cancers, those treated with induction chemotherapy + CRT had more advanced features than those treated with CRT alone (cT3: 80% vs. 43%, cN+: 62% vs. 10%, tumour size: 3.4 vs. 2.3 cm; all p < 0.001). TNT with induction chemotherapy is the predominant neoadjuvant approach in French expert centres. Tumour classification, location and patient age significantly influence treatment choices, reflecting a shift towards personalized context-specific care.