Factors Predicting the Quality of Total Mesorectal Excision for Rectal Cancer

Objective: To determine preoperative tumor-, patient-, and treatment-related factors that are independently associated with incomplete mesorectal excision. Summary of Background Data: 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. Methods: 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. Results: 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. Conclusion: 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.