[Application of ultrasound-guided perianal sphincter injection of botulinum toxin A in sphincter-preserving surgery for male ultra-low rectal cancer under 3D laparoscopy].

Objective

To investigate the safety and preliminary efficacy of ultrasound-guided perianal sphincter injection of botulinum toxin type A (BTX-A) in sphincter-preserving surgery in male patients with ultra-low rectal cancer.

Methods

A descriptive case series study was conducted. The clinical data of 25 consecutive male patients with ultra-low rectal cancer who underwent sphincter-preserving surgery with a preoperative botulinum toxin type A (BTX-A) injection strategy in the Department of Gastrointestinal Surgery, Henan Provincial People's Hospital from January 2022 to January 2024 were retrospectively analyzed. All patients presented with a difficult pelvis or a tight anal sphincter identified by preoperative digital rectal examination. Patients received an ultrasound-guided injection of 100 U of BTX-A into the external anal sphincter 1 month preoperatively. The main outcome measures included the surgical success rate, perioperative parameters (operative time, intraoperative blood loss, and length of hospital stay), the rate of prophylactic stoma, postoperative complications, and the Low Anterior Resection Syndrome (LARS) score at 6 months postoperatively.

Results

All 25 patients successfully underwent 3D laparoscopic sphincter-preserving surgery without conversion to open surgery or perioperative mortality. The mean operative time was (235.2±48.4) minutes, and the mean intraoperative blood loss was (80.4±35.9) ml. The mean postoperative hospital stay was (13.7±4.9) days. Only 2 patients (8%) underwent prophylactic stoma creation. The postoperative complication rate was 12% (3/25), including 1 case (4%) of anastomotic leakage, 1 case (4%) of perianal infection, and 1 case (4%) of urinary retention. All patients achieved recovery and were discharged from the hospital subsequent to undergoing symptomatic conservative treatment. No patient developed distal rectal ischemia/necrosis or anastomotic stenosis. At 6 months postoperatively, the mean LARS score was (21.7±6.1), and the incidence of major LARS was 12% (3/25).

Conclusions

For male patients with ultra-low rectal cancer presenting with a difficult pelvis or a tight anal sphincter, preoperative ultrasound-guided injection of BTX-A into the anal sphincter is a safe and feasible novel technique.