Primary hepatic neuroendocrine carcinoma in a child. Morphologic, immunocytochemical, and molecular biologic studies.

BACKGROUND

Primary neuroendocrine tumor of the liver is uncommon, and virtually all reported patients with the tumor have been adults. Most of the tumors were carcinoids. The authors report an 8-year-old girl with primary hepatic neuroendocrine carcinoma.

METHODS

Histologic, ultrastructural, and immunocytochemical studies and Southern blot analysis of tumor N-myc DNA were performed in the patient.

RESULTS

Histologically, the tumor revealed a characteristic organoid pattern with a spectrum of differentiation varying from well-differentiated carcinoid-like areas to poorly differentiated pleomorphic areas. Ultrastructural features included neurosecretory granules and interdigitating cytoplasmic extensions. The tumor cells showed immunoreactivity to neuron-specific enolase (NSE), S-100 protein, chromogranin, and synaptophysin. No evidence of amplification of tumor N-myc DNA was present. However, the molecular weight of the tumor N-myc DNA (1.8 kb) was significantly lower than the normal control (from normal liver tissue) (2.0 kb).

CONCLUSIONS

This report documents the occurrence of primary hepatic neuroendocrine carcinoma in a child. Thorough studies and complete clinical evaluation are essential to the establishment of diagnosis. The result of N-myc DNA analysis probably is attributable to deletion of part of the tumor N-myc gene. The clinical implication of this finding is unknown, and additional investigation is warranted.