Primary ovarian non-small cell neuroendocrine carcinoma in an adolescent: The youngest case reported to date.

Ovarian non-small cell neuroendocrine carcinoma (NSCNEC) is a rare, aggressive tumor accounting for < 1% of ovarian neoplasms; all reported cases were in adults, the youngest being 18 years [3]. We report a 15-year-old girl-to our knowledge the youngest patient with primary ovarian NSCNEC in the literature. She presented with acute abdominal pain and a large cystic-solid abdominopelvic mass. Emergency fertility-sparing cytoreductive surgery established the diagnosis of NSCNEC by histopathology and immunohistochemistry. Immunohistochemistry (Fig. 1) showed neuroendocrine marker positivity (Syn, CgA, CD56, INSM1), BRG1 (+), and Inhibin-α-positive stromal cells with pericellular reticulin; CK20 and CDX2 were additionally positive, indicating intestinal-type differentiation, whereas germ cell markers (SALL4 and others) were negative. FIGO stage was IIIB. She received bleomycin-etoposide-carboplatin and remained recurrence-free at 6 months. This case indicates that ovarian NSCNEC should be considered even in adolescents, supporting calls for a global registry and standardized management.