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 cholelithiasis. 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.