[Safety of the strategy of minimizing intestinal resection during surgery for pelvic radiation- induced terminal small intestinal stenosis]

Objective: To investigate the efficacy of strategies for minimizing small bowel resection during surgery for pelvic radiation-induced terminal small intestinal stenosis in preventing postoperative complications such as anastomotic leakage and short bowel syndrome. Methods: This was a retrospective cohort study. There are two subtypes of chronic radiation enteritis (CRE) with combined intestinal stenosis and intestinal obstruction: (1) Type I: terminal ileal lesions with a normal ileal segment of 2-20 cm between the ileal lesion and ileocecal junction; and (2) Type II: the lesion is located in the small bowel at a distance from the ileocecal region, usually accompanied by extensive damage to the bowel segments outside the lesion. The indications for minimal bowel resection are as follows: (1) diagnosis of Type I small bowel CRE; (2) absence of radiological evidence of rectosigmoid damage; and (3) absence of colonic obstruction. The contraindications are: (1) stenotic, penetrating lesions of the distal cecum; (2) emergency surgery; (3) recurrence of malignant tumor or history of radiotherapy for recurrent malignant tumor; (4) interval between radiotherapy and surgery <6 months; and (5) history of preoperative small bowel resection or abdominal chemotherapy. Case data of 40 patients with Type I CRE who met the above criteria and had undergone minimal bowel resection between April 2017 and December 2019 were retrospectively analyzed (minimal bowel resection group; including 13 patients from Jinling Hospital, 16 from the Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, and 11 from the Affiliated Hospital of Xuzhou Medical University). Forty patients with Type I CRE who had undergone resection of intestinal stenosis lesions and the ileocecal region between October 2015 and March 2017 were included as historical controls (conventional resection group; all from Jinling Hospital). The specific strategy for minimal bowel resection was one-stage partial ileal resection+ileo anastomosis+protective small bowel stoma. In contrast, conventional resection comprised ileocecal resection+ileocecal-ascending colon anastomosis. Postoperative complications, intraoperative and postoperative recovery, and changes in postoperative quality of life were analyzed in both groups. The severity of postoperative complications was assessed by Clavien-Dindo and the Comprehensive Complication Index (CCI). Karnofsky performance scores (KPS) were used to evaluate the quality of life of patients in the two groups preoperatively and postoperatively. The higher the KPS score, the better the quality of life. Results: Baseline patient characteristics did not differ significantly between the two groups (P>0.05). Compared with the conventional resection group, the length of small bowel resected in the minimal bowel resection group (51 [20-200] cm vs. 91 [60-200] cm, Z=5.653, P<0.001), duration of postoperative total enteral nutrition [9 (3-18) days vs. 12 (4-50) days, Z=2.172, P=0.030], and duration of postoperative hospital stay [17 (9-24) days vs 29 (13-57) days, Z=6.424, P<0.001] were shorter; all of these differences are statistically significant. The overall incidence of postoperative complications was lower in the minimal bowel resection group than in the conventional resection group [20.0% (8/40) vs. 70.0% (28/40), χ2=19.967, P<0.001], These comprised short bowel syndrome [5.0% (2/40) vs. 25.0% (10/40), χ2=6.274, P=0.012], anastomotic leakage or fistula [2.5% (1/40) vs. 22.5% (9/40), χ2=7.314, P=0.014], and pleural effusion [7.5% (3/40) vs. 25.0% (10/40), χ2=4.500, P=0.034], all of which occurred less often in the minimal bowel resection than conventional resection group. The CCI index was also lower in the minimal bowel resection group than in the conventional resection group [CCI>40: 2.5% (1/40) vs. 12.5% (5/40), Z=18.451, P<0.001]. KPS scores were higher in the minimal bowel resection group 1 and 3 months postoperatively than they had been 1 day preoperatively (79.9±4.7 vs. 75.3±4.1, 86.2±4.8 vs. 75.3±4.1, both P<0.05). In the minimal bowel resection group, seven patients were satisfied with their current quality of life and refused to undergo stoma reduction at follow-up and one deferred stoma reduction because of rectal bleeding. The remaining 32 patients underwent stoma reduction 3 to 12 months after surgery, 26 of whom underwent ileo-cecal anastomosis. The remaining six underwent resection of the stoma and anastomosis of the ileum to the ascending colon. Conclusions: The strategy of minimal small bowel resection in patients with radiation-induced bowel injuries reduces the length of resected small bowel, decreases the risk and severity of postoperative complications, and is associated with a better prognosis and quality of life than conventional resection.