Small cell neuroendocrine carcinoma of the maxillary sinus--a case report and nude mouse transplantable model.

Abstract

A rare case of small cell neuroendocrine carcinoma (SNEC) arising in the maxillary sinus is presented, and a SNEC tumor line serially transplantable in nude mice was established. Tumor marker for SNEC is also discussed. The tumor tissues obtained from operated material were heterotransplanted subcutaneously into nude mice. Histopathologic studies and immunoradiometric assays for NSE and pro-GRP in serum were performed. The primary lesion was composed of tumor nests of small cells with hyperchromatic nuclei and was positive for NSE and chromogranin A immunohistochemically. Serum levels of NSE and pro-GRP changed dynamically, reflecting the clinical status. Nude mouse tumor showed similar histologic features to those of original tumor and expressed NSE. Neuroendocrine granules were detected in tumor cells in electron microscopy. Serum NSE level in nude mice was elevated in proportion to the relative tumor weight. Serum NSE and pro-GRP were useful tumor markers for extrapulmonary SNEC. A SNEC tumor transplantable in nude mice would provide a valuable model for characterization of this lesion.