Microscopic intramural extension of rectal cancer after neoadjuvant chemoradiation: A meta-analysis based on individual patient data.

CONCLUSION: Based on this meta-analysis, in order to treat the MIS for 95% of rectal cancer patients after CRT, a Clinical Target Volume (CTV) margin of 5.5 mm from the lateral most edge of the macroscopic tumor would suffice. 80% of tumors showed no MIS and would not require an extra CTV margin for treatment. These findings support the feasibility of localized radiotherapy boosts for dose-escalation to improve response among patients with incomplete response after standard CRT and can also be applied in the surgical setting.
PMID: 31710942 [PubMed - as supplied by publisher]

Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology - November 7, 2019 Category: Radiology Authors: Verrijssen AS, Guillem J, Perez R, Bujko K, Guedj N, Habr-Gama A, Houben R, Goudkade D, Melenhorst J, Buijsen J, Vanneste B, Grabsch HI, Bellezzo M, Paiva Fonseca G, Verhaegen F, Berbee M, Van Limbergen EJ Tags: Radiother Oncol Source Type: research