S4486 In Hot Water: Neurogastroenterology and Motility Sequelae of Cytoreductive Surgery (CRS) Plus Hyperthermic Intraperitoneal Chemotherapy (HIPEC)

Introduction: Radical surgery with regional chemotherapy has proven survival benefits in the management of peritoneal carcinomatosis from colorectal, appendiceal, gastric, and ovarian cancers. We present a case series of neurogastroenterology and motility sequelae in 3 patients with abdominal cancers and peritoneal metastasis who were treated with cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). Case Description: A 58-year-old woman with high-grade appendiceal cancer underwent right hemicolectomy, peritonectomy, and omentectomy with HIPEC (mitomycin-C). Over months, she developed intense, episodic, abdominal cramping/distention, nausea and vomiting. Computed tomography (CT) scan showed dilated small bowel loops without obstruction. Small bowel follow-through showed barium transit time >6 hours. Gastric emptying scan and Sitz marker study were normal. A diagnosis of chronic intestinal pseudo-obstruction was made, and she was successfully treated with prucalopride and pyridostigmine. A 47-year-old woman with stage IV-B serous ovarian cancer underwent hysterectomy, bilateral salpingo-oophorectomy, peritonectomy, omentectomy, and right hemicolectomy followed by adjuvant chemotherapy. Positron emission tomography/CT scan showed recurrent peritoneal metastases requiring secondary cytoreduction with HIPEC (cisplatin/paclitaxel). Six months later, she had diarrhea, steatorrhea, unintentional weight loss, alopecia, and vitamin D deficiency. She was diagnosed with exocrine pancreatic insufficiency with a fecal elastase level of 38. Symptoms improved remarkably on pancreatic enzyme replacement therapy. A 76-year-old man with stage IV sigmoid colon cancer underwent systemic chemotherapy with substantial decrease in peritoneal disease followed by CRS (anterior resection of the rectum, sigmoid resection, peritonectomy and omentectomy) with HIPEC (oxaliplatin). One-year follow-up revealed no signs of local recurrence or distal metastases. Post CRS with HIPEC, he developed ongoing postprandial nausea, emesis, and bloating. A gastric emptying scan confirmed the diagnosis of gastroparesis, and he was managed with metoclopramide and antiemetics. Discussion: CRS with HIPEC has altered the treatment landscape of abdominal cancers with peritoneal metastasis. Understanding complications of this synergistic approach is essential for enhancing patient outcomes and surgical oncology techniques. Despite the risks, careful patient selection and expertise of specialized institutions can lead to acceptable morbidity and management of post-interventional gastrointestinal sequelae.