[Short-term outcome of transanal total mesorectal excision for male low rectal cancer patients with "difficult pelvis" : a single center report from Peking University Cancer Hospital].

Objective To explore the applicable value of transanal total mesorectal excision (taTME) in male low rectal cancer patients with narrow pelvis- "difficult pelvis" , which remains difficult for both open and laparoscopic sphincter-saving operations. Methods Clinical data of male low rectal cancer patients diagnosed by pathology undergoing taTME between June 2016 and January 2018 at Peking University Cancer Hospital were collected. A retrospective cohort study was performed. Patients were selected according to the following criteria: (1) low rectal cancer, the distance between inferior margin of tumor and anal verge ≤ 5 cm; (2) the distance between two sciatic tubercles 25 kg/m2; (4) tumor horizontal diameter ≤ 4 cm. Operation time, intraoperative blood loss, postoperative hospital stay, postoperative complications and anal function were analyzed. Results A total of 20 patients were included in this study. All the patients received preoperative neoadjuvant chemoradiation and hybrid transabdominal and transanal surgery. The median BMI was 27.7 (26.2-36.4) kg/m2; the median distance between two sciatic tubercles was 92.5 (78-100) mm; the median distance between the inferior margin of tumor to the anal verge was 4 (2-5) cm; the median operation time was 302 (215-402) min; the median intraoperative blood loss was 100 (50-200) ml; the median postoperative hospital stay was 9 (5-15) d. Postoperative complications occurred in 5 patients (25%) , including 3 pelvic infection, 1 intestinal obstruction, 1 anastomotic leakage receiving sigmoid colostomy. There was no perioperative death. Sphincter-preservation rate was 100%. Nineteen patients received anal manometry 1 month after operation with normal resting pressure (41.5±8.6) mmHg and squeeze pressure (121.0±11.6) mmHg. All the patients were followed up to March 2018, and the median follow-up time was 4.5 months. Only 1 patient had supraclavicular lymph node metastasis and no local recurrence was found. Conclusions The safety of transanal total mesorectal excision for male patients with low rectal cancer and difficult pelvis is acceptable. TaTME is helpful to preserve the anal sphincter. Key words: Transanal total mesorectal excision; "Difficult pelvis"; Low-lying rectal cancer; Anal sphincter preservation