Palliative Transverse Blowhole Colostomy to Address Distal Colonic Obstruction in Advanced Peritoneal Malignancies: A Case Series.

BACKGROUND: Distal colonic obstruction in patients with peritoneal carcinomatosis due to advanced peritoneal surface malignancy (PSM) can present significant challenges. Unfavorable anatomic factors, colonic distention, and poor nutritional status may preclude conventional resection or loop colostomy. Transverse blowhole colostomy (TBC) may provide a safe and less invasive option for rapid decompression and symptom palliation. METHODS: We performed a retrospective review of adult patients with unresectable PSM and symptomatic distal colonic obstruction who underwent TBC by a single surgeon at an NCI-designated Comprehensive Cancer Center between September 2022 and October 2024. Demographic, clinical, operative, and postoperative outcomes were evaluated. RESULTS: Six patients underwent TBC for distal colonic obstruction secondary to advanced PSM, including colorectal and appendiceal adenocarcinoma, retroperitoneal sarcoma, and primary peritoneal carcinoma. Mean operative time was 64 minutes. TBC was successfully created in all patients, including one in whom laparoscopic loop colostomy was not possible because of extensive peritoneal disease. All patients experienced immediate relief of obstructive symptoms and tolerated a regular diet by postoperative day 1 or 2. No complications directly attributable to TBC occurred. Postoperative survival varied substantially, ranging from 2 days to 20 months, with two patients alive at the time of publication. CONCLUSION: TBC is a technically feasible, low-morbidity option for rapid decompression and palliation of distal colonic obstruction in carefully selected patients with advanced, unresectable PSM. Limited requirement for colonic mobilization or intra-abdominal exploration may make it particularly useful when extensive carcinomatosis or a fixed, distended colon makes conventional diversion difficult.