Mesorectal grades predict recurrences after curative resection for rectal cancer.

PURPOSE: Local recurrence after curative excision for rectal cancer is frequently regarded as a failure of surgery. The macroscopic quality of the excised mesorectum after total mesorectal excision has been proposed as a means of assessment of the adequacy of surgery. This study was designed to determine the utility of mesorectal grading in prediction of local and overall recurrence after curative surgery. METHODS: All patients undergoing resection for primary adenocarcinoma of the rectum had a mesorectal grading prospectively applied to their resection specimens, according to the classification proposed by Quirke et al. (Grades 1-3; 3 is the best). The outcome of patients undergoing potentially curative surgery from 2001 to 2003 was reviewed. Prognostic significance of mesorectal grades was determined by multivariate regression analyses. RESULTS: A total of 130 patients with a median follow-up of 26 (range, 17-42) months were studied. The local and overall recurrences were 8.4 and 15 percent, respectively. The mesorectum was reported as Grade 3 in 61 patients (47 percent), Grade 2 in 52 patients (40 percent), and Grade 1 in 17 patients (13 percent). Patients with Grade 1 mesorectum had 41 percent local recurrence and 59 percent overall recurrence, respectively. However, patients with Grade 2 and Grade 3 mesorectum had 5.7 and 1.6 percent local recurrences, respectively, and 17 and 1.6 percent overall recurrence, respectively. By Cox's regression analysis, grade of mesorectum independently influenced both local and overall recurrences. CONCLUSIONS: The macroscopic quality of mesorectum after curative excision of rectal cancer is an important predictor of local and overall recurrences. The mesorectal grades may be of value in decisions regarding postoperative adjuvant therapy.