Factors predicting the quality of total mesorectal excision for rectal cancer

To determine preoperative tumor-, patient-, and treatment-related factors that are independently associated with incomplete mesorectal excision.

Incomplete total mesorectal excision (TME) for rectal cancer is associated with increased local and overall recurrences. Factors predicting incomplete mesorectal excision have scarcely been studied.

In the context of PROCARE, a Belgian multidisciplinary project on rectal cancer, the quality of 266 consecutive and anonymized TME specimens submitted by 33 candidate-TME-trainers was graded by a blinded pathology review board in a standardized manner. Uni- and multivariable analysis were performed to identify factors that can independently predict incomplete mesorectal excision.

Mesorectal resection was complete in 21%, nearly complete in 47%, and incomplete in 32%. Of 57% of TME specimens the grade of resection had not been reported by the local pathologist. Incomplete TME doubled the incidence of a positive circumferential resection margin (P = 0.004). Factors found to be significantly related to incomplete TME in univariate analysis were as follows: surgeon, female gender, pathologic body mass index, low rectal cancer, negative clinical nodal status, the absence of downstaging after long-course chemoradiation, laparoscopic and converted laparoscopic resection, and abdominoperineal resection. Multivariable analysis identified pathologic body mass index (P = 0.017), the absence of downstaging after long-course chemoradiation (P = 0.0005), and laparoscopic or converted laparoscopic resection (P = 0.014) as factors that are independently associated with incomplete mesorectal excision.

Good TME quality cannot be guaranteed. This peer-reviewed TME assessment revealed a number of factors that are independently related to incomplete TME. Both specimen and pathology report need to be audited.