The Modern Abdominoperineal Excision: The Next Challenge After Total Mesorectal Excision

Abstract

In Brief Objectives: Examine the cause of local recurrence (LR) and patient survival (S) following abdominoperineal resection (APR) and anterior resection (AR) for rectal carcinoma and the effect of introduction of total mesorectal excision (TME) on APR. Methods: A total of 608 patients underwent surgery for rectal cancer in Leeds from 1986 to 1997. CRM status and follow-up data of local recurrence and patient survival were available for 561 patients, of whom 190 underwent APR (32.4%) and 371 AR (63.3%). Also, a retrospective study of pathologic images of 93 specimens of rectal carcinoma. Results: Patients undergoing APR had a higher LR and lower survival (LR, 22.3% versus 13.5%, P = 0.002; S, 52.3% versus 65.8%, P = 0.003) than AR. LR free rates were lower in the APR group and cancer specific survival was lowered (LR, 66% versus 77%, log rank P = 0.03; S, 48% versus 59%, log rank P = 0.02). Morphometry: total area of surgically removed tissue outside the muscularis propria was smaller in APR specimens (n = 27) than AR specimens (n = 66) (P < 0.0001). Linear dimensions of transverse slices of tissue containing tumor, median posterior, and lateral measurements were smaller (P < 0.05) in the APR than the AR group. APR specimens with histologically positive CRM (n = 11) had a smaller area of tissue outside the muscularis propria (P = 0.04) compared with the CRM-negative APR specimens (n = 16). Incidence of CRM involvement in the APR group (41%) was higher than in the AR group (12%) (P = 0.006) in the 1997 to 2000 cohort. Similar results (36% and 22%) were found in the 1986 to 1997 cohort (P = 0.002). Conclusions: Patients treated by APR have a higher rate of CRM involvement, a higher LR, and poorer prognosis than AR. The frequency of CRM involvement for APR has not diminished with TME. CRM involvement in the APR specimens is related to the removal of less tissue at the level of the tumor in an APR. Where possible, a more radical operation should be considered for all low rectal cancer tumors. Patients with primary rectal carcinoma treated by abdominoperineal resection (APR) had a higher rate of circumferential resection margin involvement, a higher local recurrence, and poorer prognosis than those treated with anterior resection (AR). The higher incidence of CRM involvement and thus incomplete excision in the APR specimens is related to the removal of less tissue at the level of the tumor in an APR compared with an AR. This is due to the natural coning of the base of the mesorectum and the current standard surgical approach of creating the circumferential margin on the anal sphincter. A modification of the modern surgical techniques and an increased use of neoadjuvant therapy are required in these patients.