Management strategies for pT1 rectal cancer following local excision: Insights from a national survey by the AIRO gastrointestinal study group

Purpose

This national survey aimed to evaluate current clinical practices for managing pT1 rectal cancer post-local excision (LE) in Italian radiotherapy (RT) centers, focusing on high-risk cases.

Materials and methods

Conducted from July to October 2024, a cross-sectional survey with 40 questions was distributed to 183 heads of radiation oncology departments. Quantitative data were collected through closed-ended questions, while qualitative feedback was grouped thematically.

Results

The survey yielded responses from 54 centers. Multidisciplinary team discussions were common (96.2 %). Surgical re-excision or total mesorectal excision (TME) was the primary management for high-risk cases, with RT used in only 7.4 % of cases, primarily for patients declining surgery. Key local recurrence risks identified by respondents include deep margin <1 mm (96.2 %), high tumor grading (72.2 %), lymphovascular infiltration (64.8 %), and tumor budding (51.9 %). For regional recurrence, the main risk factors identified were lymphovascular infiltration (90.7 %), high tumor grading (83.3 %), and perineural infiltration (72.2 %). Significant variability was observed in RT techniques and target volumes. Elective volume recommendations were split between 45 Gy and 50 Gy, while surgical bed doses ranged from 50–50.4 Gy to 54–55 Gy. Most centers included the complete mesorectum and elective lymph nodes in treatment volumes, though some limited treatment to the surgical scar and mesorectum. Follow-up practices also showed considerable heterogeneity.

Conclusion

This survey highlights significant variability in pT1 rectal cancer management post-LE across Italian centers, underscoring the necessity for standardized guidelines, and providing a foundation for future multicenter studies to optimize patient care.