Background: After abdominoperineal excision (APE), the presence of tumor cells in the circumferential resection margin (R1) and iatrogenic tumor perforations are still frequent and result in an increased rate of local recurrences. In this study, a standardized supine APE with an increased focus on the perineal dissection (sPPD) is compared to the customary supine APE.
Methods: From 2000 to 2010, a total of 246 patients underwent APE for rectal cancer (sPPD and customary supine APE). All patients were staged with preoperative magnetic resonance imaging (MRI) and received neoadjuvant treatment (n = 203) when margins were involved or threatened (cT3 + and T4). As a result of a quality improvement program in 2006, the surgical technique was modified: it became standardized, emphasis was placed on the perineal dissection, and pelvic dissection was limited to avoid false routes when following the total mesorectal excision planes deep into the pelvis.
Results: Overall, the percentage of involved circumferential resection margins (CRMs) was 10%. In the period before introducing sPPD, the R1 percentages for cT0-3 and cT4 tumors were 6.8 and 30.2%, compared to 2.2 and 5.7% after introduction of sPPD (P = 0.001). Risk factors for R1 resection were preoperative T4 tumors (14.9%, P = 0.011), tumor perforation (33.3%, P = 0.002), fistulating tumors (35.7%, P = 0.002), mucus-producing tumors (23.1%, P = 0.006), or bulky tumors (66.7%, P < 0.001).
Conclusions: The objective of surgical treatment of low rectal cancer is to obtain negative resection margins and subsequently reduce the risk of local recurrence. A combination of the appropriate preoperative treatment and standardized surgical technique such as sPPD can achieve this goal.