Unknown primary large-cell neuroendocrine tumor

Hypercalcemia and Bone Metastasis in a Case of Large Cell Neuroendocrine Carcinoma With Unknown Primary

Large cell neuroendocrine carcinoma (LCNEC) constitutes a rare subset of highly undifferentiated malignancies known for their aggressive nature. Although these tumors commonly originate in the lungs and gastrointestinal tract, their potential occurrence is not restricted to specific anatomical sites, giving rise to a variety of symptoms. Notably, cases of neuroendocrine tumors (NETs) with an unidentified primary source exhibit a graver prognosis and shorter survival periods compared to those with clearly identified origins. NETs frequently demonstrate a propensity to metastasize, spreading to diverse anatomical regions such as the liver, lungs, lymph nodes, and bones, illustrating their aggressive nature and the complexity of their management. In this context, we present the case of a 59-year-old male who sought medical attention in the emergency department due to right upper quadrant (RUQ) abdominal pain. Initial diagnostic assessments revealed significantly elevated liver function tests and severe hypercalcemia. A right upper quadrant ultrasound (RUQ US) was subsequently performed, which revealed heterogeneous hepatic echotexture with innumerable echogenic masses, suggesting a metastatic process. A computed tomography (CT) scan was then ordered to evaluate further the RUQ US findings, which showed numerous hypovascular liver masses, raising concerns of malignancy. A liver biopsy confirmed a diagnosis of LCNEC with an unidentified primary source.

Systematic review of neuroendocrine carcinomas of the oropharynx

Data describing features and management of oropharyngeal neuroendocrine carcinomas (NEC) remain sparse. A systematic review was performed. Patients were stratified by treatment modality and examined for disease progression and survival outcomes. Ninety-four patients from 50 publications were included. Average age at diagnosis was 59.7 years (range 14-83). 73.4% were male. Most studies did not document HPV status. Forty patients (85.1%) were p16 positive, and 34 (85.0%) were HPV-ISH positive. Overall survival was 75.4% at 1 year, and 40.0% at 2 years. Of patients with locoregional disease, 33.8% developed distant metastasis. 12.5% of patients developed locoregional recurrence. Patients who developed distant metastases had worse overall survival (p = 0.0004). No significant difference was found between treatment modalities. Human papilloma virus may be associated with oropharyngeal NEC. Current treatments provide locoregional control, but distant metastases are common and confer low overall survival.