Short-term Clinical Observation Of Laparoscopic Intersphincteric Resection Combined With Intraoperative Radiotherapy For Ultra-low Rectal Cancer

Background:For low rectal cancer,the traditional Mile's procedure of resection of the anus and permanent colostomy not only reduces the quality of postoperative life of the patient,but also brings greater psychological trauma to the patients.As an extreme anus preservation technique,laparoscopic intersphincteric resection(LISR)enhances the rate of anus preservation in low rectal cancer.INTRABEAM(Carl Zeiss,Germany)intraoperative radiotherapy(IORT)using low energy X-rays features in accurate irradiation,less exposure,and reduced complications.To further reduce the risk of local recurrence and improve local control,our center takes advantages of LISR and INTRABEAM IORT in the treatment of low rectal cancer.This study observed the short-term clinical efficacy in local recurrence,short-term postoperative complications,and anal function within 1 year after surgery to evaluate the treatment safety.Patients and Methods:From August 2017 to July 2019,we retrospectively analyzed the short-term outcomes of 10 patients evaluated preoperatively with T2 or T3low rectal cancer.They all had received LISR and INTRABEAM IORT with a dose of 16-18 Gy applied by an applicator through the anus(natural orifice)in our single center.Then,with no pre-or postoperative radiotherapy given,the patients were suggested to receive 8 cycles of the XELOX chemotherapy regimen(oxaliplatin,130 mg/m~2 and capecitabine,1000 mg/m~2).By analyzing the short-term complications,imaging and laboratory results,anal function evaluation,acute radiation injury,urinary function and sexual function questionnaires,the clinically short-term clinical outcomes of the patients were observed.Results:Ten patients,including two females and eight males,all achieved R0resection.The mean time of surgery and IORT was 332.50±25.31 min,the mean time of IORT was 26.60±2.23 min,the mean intraoperative blood loss was 216.80±29.25 ml,and the mean radiation dose was 16.5±0.19 Gy.The mean first time of postoperative exhaust was 3.50±0.35 days,the mean removal time of the urinary catheter was 4.70±0.96 days,the mean removal time of the abdominal drainage tubes was 6.20±2.14 days,and the mean recovery time of full liquid food was 4.60±0.62 days.The mean hospital stay was 13.20±2.70 days.The postoperative pathology was 5 patients in T2 and T3 patients and circumferential resection margins were all negative.The mean distance from the lower edge of the tumor to the anal verge was 3.96±0.16 cm.The mean number of total lymph nodes harvested was 20.00±3.59,and the average number of lymph nodes at the foot of the inferior mesenteric artery was 4.50±2.84.Seven patients underwent 8 cycles of XELOX chemotherapy.No local recurrence,distant metastasis,or death has occurred.One patient occurred a perianal infection and occurred postoperative anastomotic stenosis later.Compared with the preoperative anal manometry results,the patient's postoperative anal resting pressure was significantly reduced,and the anal squeezing pressure was slightly reduced.Compared with the results of the first month after ileostomy reversal,the anal resting pressure and squeezing pressure improved after the third month after ileostomy reversal.The Saito function questionnaire indexes and Wexner score also improved.Defecation frequencies and the number of pads use were relatively reduced,and patients were satisfied with the results of postoperative anal function.No symptoms of acute radiation injury or symptoms of urinary or sexual dysfunction were observed.Conclusions:For patients evaluated preoperatively with T2 or T3 ultra-low rectal cancer,following the strict indications,LISR with INTRABEAM IORT using low energy X-rays can persevere anus and improve local control with less risk of complications after surgery.Although the short-term clinical efficacy is safe,the long-term clinical efficacy needs further observation.