Meta-Analysis of Oncological Outcome After Abdominoperineal Resection or Low Anterior Resection for Lower Rectal Cancer

Abstract

In lower rectal cancer, postoperative outcome is still subject of controversy between the advocates of abdominoperineal resection (APR) and low anterior resection (LAR). Reports suggest that low anterior resection may be oncologically superior to abdominoperineal excision, although no good evidence exists to support this. Publications were identified which assessed the differences comparing 5-year survival, local recurrence, circumferential resection margin rate, complications and so on. A meta-analysis was performed to clarify the safety and feasibility of the two procedures with several types of outcome measures. A total of 13 studies met the inclusion criteria, and comprised 6,850 cases. Analysis of these data showed that LAR group was highly correlated with 5-year survival (pooled OR = 1.73, 95%CI: 1.30–2.29, P = 0.0002 random-effect). And local recurrence rate of APR group was significantly higher than that in LAR group (pooled OR = 0.63, 95%CI: 0.53–0.75, P < 0.00001 fixed-effect). Also, the circumferential resection margin (CRM) were high involved in APR group than in LAR group. (5 trials reported the data, pooled OR = 0.43, 95%CI: 0.36–0.52, P < 0.00001 fixed-effect). Besides, the incidents of overall complications of APR group was higher compared with LAR group (pooled OR = 0.52, 95%CI: 0.29–0.92, P = 0.03 random-effect). Patients treated by APR have a higher rate of CRM involvement, a higher local recurrence, and poorer prognosis than LAR. And there is evidence that in selected low rectal cancer patients, LAR can be used safely with a better oncological outcome than APR. due to the inherent limitations of the present study, for example, the trails available for this systematic review are limited and the finite retrospective data, future prospective randomized controlled trials will be useful to fully investigate these outcome measures and to confirm this conclusion.

Prospective study on image‐guided navigation surgery for pelvic malignancies

“…At pathology, all cases were evaluated as no ink on the tumor. These results are positive compared with the literature, where approximately 15% to 30% positive resection margins are reported in these challenging cases …”

“…[14][15][16] In the current study, only one out of are reported in these challenging cases. 17,18 Of the 36 lymph node targets, which were all located outside the mesorectum, 33 were successfully removed. The three missed lymph node targets were all located at the obturator region, and their size was decreased to 3, 3, and 5 mm due to neoadjuvant CRT.…”

The anatomy of the perineal body in relation to abdominoperineal excision for low rectal cancer

“…The object is to achieve a tumour‐free circumferential resection margin (CRM) to reduce the risk of local recurrence . Patients with low rectal tumours requiring an abdominoperineal excision (APE) may have a poor prognosis . The operation is associated with higher rates of CRM involvement, tumour perforation and incomplete surgical removal compared with anterior resection for more superiorly located rectal tumours .…”

The role of the longitudinal muscle in the anal sphincter complex

“…Low rectal cancer is a challenging disease, particularly when the tumor invades the anal sphincter complex (ASC). These tumors are typically removed by an abdominoperineal excision (APE), although patients requiring this type of surgery end up with a permanent colostomy and have a poorer oncological outcome compared to anterior resection (Wang et al, ). Damage to the anal sphincters, iatrogenic tumor perforation and incomplete tumor resection are frequently encountered and related to increased local recurrence and decreased survival (den Dulk et al, ).…”