title: Incidence and morbidity of cholelithiasis in patients receiving chronic octreotide for metastatic carcinoid and malignant islet cell tumors.
abstract: BACKGROUND
  Octreotide, a long-acting somatostatin analogue, has demonstrated clinical utility in patients with carcinoid syndrome and malignant islet cell tumors of the pancreas. Prior studies have reported a greater than expected incidence of cholelithiasis in patients treated with octreotide for acromegaly. This study attempted to determine the incidence and morbidity of cholelithiasis in a group of patients with metastatic carcinoid or malignant pancreatic islet cell tumors who were receiving chronic therapy with octreotide.
  
  
  METHODS
  Forty-four of 55 patients on investigational protocols with octreotide were eligible for chart review; 10 patients were excluded due to prior cholecystectomy and 1 patient due to asymptomatic cholelithiasis at presentation. Patients fell into three treatment groups. The low dose (LD) group was comprised of 17 patients receiving 150 microg of subcutaneous octreotide 3 times a day. Twenty-one patients received high dose (HD) therapy comprised of 500 microg given 3 times a day. The low dose-high dose (LD-HD) group was comprised of 6 patients who had their dose escalated from 150 microg to 225-500 microg of octreotide 3 times a day.
  
  
  RESULTS
  The overall incidence of cholelithiasis and/or gallbladder sludge was found to be 52.3% in all 3 treatment groups. Three of the 44 patients (6.8%) had symptomatic disease requiring emergency cholecystectomy. Five other patients underwent elective or incidental gallbladder surgery. The incidence of cholelithiasis in the LD, LD-HD, and HD groups was 35.3%, 66.6%, and 61.9%, respectively. The incidence of acute cholecystitis in the three groups was 11.8%, 0%, and 4.8%, respectively.
  
  
  CONCLUSIONS
  Although greater than 50% of patients receiving octreotide developed cholelithiasis, a much smaller percentage of patients had symptomatic gallbladder disease. Patients receiving chronic octreotide treatment require monitoring for the development of gallstones. However, prophylactic cholecystectomy is not indicated, unless it is performed in conjunction with bowel resection or cytoreductive hepatic surgery.
authors.affiliation: Department of Medical Oncology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: M C
authors.initials: MC
authors.lastname: Trendle
authors.forename: C G
authors.initials: CG
authors.lastname: Moertel
authors.forename: L K
authors.initials: LK
authors.lastname: Kvols
mesh_terms: D007516:Adenoma, Islet Cell / Q000188:drug therapy*; D018931:Antineoplastic Agents, Hormonal / Q000009:adverse effects* / Q000627:therapeutic use; D002276:Carcinoid Tumor / Q000188:drug therapy* / Q000556:secondary; D002769:Cholelithiasis / Q000139:chemically induced*; D006801:Humans; D015282:Octreotide / Q000009:adverse effects* / Q000627:therapeutic use; D010190:Pancreatic Neoplasms / Q000188:drug therapy*
chemical_list: D018931:Antineoplastic Agents, Hormonal; D015282:Octreotide