Abstract: Objective:To investigate the longterm efficacy of pure transanal total mesorectal excision (PtaTME) for middlelow rectal cancer.
Methods:The retrospective descriptive study was conducted. The clinicopathological data of 18 patients with middlelow rectal cancer who were admitted to the Sixth Affiliated Hospital of Sun Yatsen University from July 2014 to August 2016 were collected. There were 7 males and 11 females, aged (58±13) years, with a range from 40 to 84 years. The body mass index was (22±3)kg/m². All the 18 patients underwent PtaTME. Observation indicators: (1) surgical and postoperative conditions; (2) postoperative pathological examination; (3) follow-up and survival. Followup using inpatient reexamination, outpatient examination, and telephone interview were performed to detect anastomotic complications, anal function, urinary retention, sexual dysfunction, survival and tumor recurrence and metastasis once every 3 months within postoperative 6 months, once every 6 months from 6 months to 3 years, and once a year after 3 years up to June 2019. The measurement data with normal distribution were represented as Mean±SD, and the measurement data with skewed distribution were represented as M (range). Count data were expressed as percentages. Survival rates were calculated by the Kaplan-Meier method.
Results: (1) Surgical and postoperative conditions: 18 patients successfully underwent PtaTME, without conversion to open surgery. The operation time, volume of intraoperative blood loss, distance between anastomosis and anal verge, time to first flatus, time to urinary catheter removal, and duration of postoperative hospital stay were (202±68)minutes, 50 mL (range, 20-400 mL), (4.5±2.0)cm, 2 days (range, 2-7 days), 3 days (range, 2-5 days), and 7 days (range, 5-10 days) in the 18 patients, respectively. There was no perioperative complication. Among 18 patients, 4 underwent preventive ileostomy. (2) Postoperative pathological examinations: the length of surgical specimens, the number of lymph node dissection, distance from tumor to the distal margin were (11.0±3.0)cm, 12±6, and 1.0 cm (range, 0.8-3.7 cm), respectively. The 18 patients had complete mesorectal membrane excision, with negative proximal margin, distal margin, and circumferential margin. Tumor pathological staging: there were 2 cases in Tis stage, 4 in T1 stage, 7 in T2 stage, and 5 in T3 stage; 16 in N0 stage, 1 in N1 stage, and 1 in N2 stage. Tumor histological classification: 2 patients had carcinoma in situ, 9 had moderately differentiated adenocarcinoma, and 7 had highdifferentiated adenocarcinoma. (3) Followup and survival: 18 patients were followed up for 34.0-59.0 months, with a median follow-up time of 57.5 months. During the follow-up, 4 patients developed grade B anastomotic leakage and were cured after conservative treatment. One patient developed anastomotic recurrence at 2 years after surgery, and no recurrence was found after surgical resection of the recurrent lesion. Four patients with prophylactic ileostomy had the stoma closured, and the anus function was satisfactory after surgery. There was no urinary retention or sexual dysfunction in the 18 patients. Of the 18 patients, 17 had tumor free survival after surgery. The 3year diseasefree survival rate was 94.4%, and the 3year overall survival rate was 100.0% in 18 patients.
Conclusion:PtaTME can achieve high quality of specimen, which is safe and feasible for the treatment of rectal cancer.