The Importance of the Pathologist's Role in Assessment of the Quality of the Mesorectum

Abstract

Total mesorectal excision (TME) is considered standard of care for rectal cancer treatment. Failure to remove the mesorectal fat envelope entirely may explain part of observed local and distant recurrences. Several studies suggest quality of the mesorectum after TME surgery as determined by pathological evaluation may influence prognosis. We aimed to determine the prognostic value of the plane of surgery as well as factors influencing the likelihood of a high-quality specimen by reviewing the literature. A pooled meta-analysis of relevant outcome data was performed where appropriate. A muscularis propria resection plane was found to increase the risk of local recurrence (RR 2.72 [95 % CI 1.36 to 5.44]) and overall recurrence (RR 2.00 [95 % CI 1.17 to 3.42]) compared to an (intra)mesorectal plane. Plane of surgery is an important factor in rectal cancer treatment and the documentation by pathologists is essential for the improvement of TME quality and patient outcome.

Fig. 1

Planes of surgery. a, whole specimen; b, on slicing

Fig. 2

Relative risk for local recurrence after a muscularis propria versus a(n) (intra)mesorectal plane (a) and for local recurrence after a mesorectal plane versus both other planes (b)

Fig. 3

Overall recurrence after a muscularis propria plane versus both other planes (a) and after a mesorectal plane versus both other planes (b)