A large cell neuroendocrine carcinoma of the gall bladder: diagnosis with 18FDG-PET/CT-guided biliary cytology and treatment with combined chemotherapy achieved a long-term stable condition.

Poorly differentiated neuroendocrine cell carcinomas of the gallbladder are rare and patients with such tumors have a poor prognosis. We describe a 64-year-old male with a large cell neuroendocrine carcinoma of the gallbladder and multiple lymph node metastases. Diagnostic excisional biopsy of the left axillary lymph nodes revealed atypical cells with predominantly large-sized round-to-oval nuclei, proliferating in a solid and focal nesting pattern. The tumor cells were positive for synaptophysin and chromogranin A, and strongly positive for Ki-67, leading to a diagnosis of poorly differentiated neuroendocrine cell carcinoma of the gallbladder, of large cell type. Using (18)F-fluorodeoxy glucose-positron emission tomography/computed tomography to determine the origin of these tumors, we observed the accumulation of (18)F-fluorodeoxy glucose in multiple large lymph nodes, a small part of the liver and the fundus of the gallbladder. Computed tomography-guided aspiration of the gallbladder showed the same pleomorphic tumor cells as the lymph nodes. The patient was diagnosed with a large cell neuroendocrine carcinoma of the gallbladder, only ∼25 mm in diameter. Combination chemotherapy with cisplatin and docetaxel, the regimen used for non-small cell lung carcinomas, and probably large cell lung carcinomas, resulted in the disappearance of the lymph node metastases and a marked improvement in the performance status for ∼22 months. The poor prognosis of patients with these aggressive tumors may be improved by the use of minimally invasive diagnostic procedures and combined systemic chemotherapy as soon as possible.