Synchronous but separate neuroendocrine tumor and high-grade dysplasia/adenoma of the gall bladder: A case report

BACKGROUND: Gall bladder neuroendocrine tumors (GB-NETs) are rare, accounting for less than 0.5% of all NETs. They usually lack specific symptoms and are difficult to diagnose preoperatively. In most cases, GB-NETs are incidentally found after cholecystectomy for large polyps or cholelithiasis, causing acute or chronic cholecystitis. The coexistence of GB-NET and GB adenocarcinoma is very rare. CASE SUMMARY: We report a case of synchronous but separate GB-NET and adenoma with high-grade dysplasia in a patient who had undergone surgery for a progressively growing GB polypoid lesion. To the best of our knowledge, simultaneous separation of NETs and cancer in the GB has not been reported. CONCLUSION: Coexistent GB carcinoid tumor and adenocarcinoma is rare. A surveillance program is needed for these large GB polyps.