Local excision of rectal cancer for cure: should we always regard rigid pathologic criteria?

The purposes of this study were to assess the relationship between the incidence of recurrence and the pathologic criteria usually applied to the selection of patients for curative local excision of rectal carcinoma and to determine whether failure to fulfill one of these criterias is always an indication for secondary abdominoperineal resection (APR).

From 1982 to 1992, 30 patients with rectal carcinoma (mean age: 69 +/- 10 years) were treated by local excision (LE). Univariate analysis of the cancer recurrence rate according to pathologic criteria was performed.

The mean follow-up was 57 +/- 40 months (range: 6-145). Five patients (17%) had recurrent disease (local in 3, distant in 1, and local and distant in 1). Two of the three local cases were successfully treated. At the end of follow-up, 90% of the patients had no evidence of recurrence, and the rectal cancer-specific death rate was 10%. Although not significant, tumor penetration beyond the submucosa and vessel or nerve invasion were associated with an increased incidence of cancer recurrence. Tumor size and differentiation, and the presence of a mucinous component were not associated with a significant increase in recurrence. According to the usual pathologic criteria proposed for curative LE, 20 patients should, theoretically, have undergone secondary APR. However, 16 of them (80%) were treated by LE only, and at the end of follow-up, 17 (85%) were alive without recurrence.

The rigid rule of systematically performing secondary APR after LE for rectal carcinoma when one or more pathologic selection criteria are not met should perhaps be reconsidered, especially for tumors exceeding 3 cm in diameter, moderately differentiated tumors, and in incidences when a mucinous component is present. However, in cases of vessel, nerve or muscular invasion, secondary APR is probably the best choice for cure.