This study showed that PPH occurred in 26% of patients with endoscopic APE for rectal cancer within 13 months after surgery and that PPC was available for prevention of PPH. The importance of PPC for preventing perineal complications was advocated by McMullin [2] and Goliger [20] in 1985. In conventional open APE, PPC is a standard procedure when sufficient peritoneal tissue is preserved [21]. Similarly, Yan et al. [24] reported that no PPH was found in 86 cases that underwent endoscopic APE with additional PPC, and that the incidence of PPH was significantly lower in endoscopic APE with than without PPC (0% vs 5.21%, p = 0.032). Nevertheless, the pelvic peritoneum is often not closed during endoscopic APE because laparoscopy is necessary for proficient suturing [22, 23]. In contrast to the previous reports about the risk factors for PPH [1, 15–18], this study did not show that PPH had any correlation with female sex, preoperative radiotherapy, or multiple organ resection including coccygectomy. Measurement of the mesenteric length was not accessible under the laparoscopic approach.
Although PPC is a useful technique to prevent PPH, some discussion remains before performing PPC. First, the peritoneum must be removed widely to avoid division of the mesorectum during medial and lateral dissection of the upper rectum from the pelvis under laparoscopy. When it is hard to perform peritoneal closure because of severe tension, addition of a shallow incision on the tense portion of the peritoneum could be helpful to relax it [24]. During suturing of the peritoneum, the stitching intervals should be shortened, because herniation of the intestine through the unexpected defect of the closed peritoneum could occur. Indeed, we did not observe herniation because interrupted stitches were placed at short intervals during peritoneal closure. Next, high proficiency is mandatory in suturing procedures by conventional laparoscopic surgery. Robotic surgery might facilitate such procedures. Finally, PPC could not be performed in some patients with endoscopic APE because of tumor invasion to the pelvic peritoneum, bulky tumor, addition of lateral pelvic lymph-node dissection, and preoperative chemoradiotherapy[25].
Various pelvic reinforcements as alternatives to PPC have been performed after APE: suture of levator ani muscle, bladder peritoneal flaps, hysteropexy, omentoplasty and synthetic mesh. Levator ani muscle suturing [26] can be applied to rectal cancer surgery because of wide excision of the muscle. A randomized trial revealed that omentoplasty did not reduce the incidence of PPH [27]. Several studies have revealed that Bio-mesh can be effective for reducing PPH [28–30]. Unfortunately, the use of Bio-mesh is limited to western countries. Immobilization of bladder peritoneal flaps in men and the uterus in women might be helpful for preventing PPH, when PPC is impossible [31, 32].
The present study had some limitations: the retrospective design, small study population, and application of the approach for lateral pelvic lymph-node dissection and PPC was decided by surgeons.