West NP et al. (2008) Pathology grading of colon cancer surgical resection and its association with survival: a retrospective observational study. Lancet. Oncol 9: 857–865

Outcomes for patients with colon cancer can be greatly improved by high-quality surgery, especially if the entire mesocolon is removed, because it contains many of the likely routes of metastatic tumor spread. Clinical trials have shown that the identification of surgical planes can predict local recurrence. West et al. hypothesized that removal of the mesocolon or colonic mesentery could increase the chance of complete eradication of a colonic cancer, and that grading the plane of surgery predicts the likelihood of local recurrence and death.

The authors of this retrospective, observational study used a prospectively collected series of specimen photographs that depicted resection of primary colonic adenocarcinoma to grade the plane of mesocolic surgical dissection, measure the amount of tissue removed and determine whether these features were associated with survival. A total of 399 excisions were graded, of which 338 were curative and 61 were palliative. Considerable variation was evident in the resections of each plane of surgery; 24% were resected in the muscularis propria plane, 44% in the intramesocolic plane and 32% in the mesocolic plane. Mesocolic-plane surgery was associated with a 15% 5-year overall survival advantage compared with surgery in the muscularis propria plane (P = 0.006). On multivariate analysis, however, this association was no longer significant.

The authors conclude that they have shown, for the first time, that quality of surgery for colon cancer is associated with patients' survival; improvements in the plane of dissection could decrease morbidity and mortality.