Adolescent-onset primary small cell neuroendocrine carcinoma of the nasal cavity: a rare and aggressive entity with Favorable outcome.

Small cell neuroendocrine carcinoma (SCNEC) of the nasal cavity is extremely rare and aggressive, particularly in pediatric and adolescent patients. We report the case of a 17-year-old Moroccan male presenting with intermittent unilateral nasal obstruction. Endoscopy revealed a vascular-appearing mass in the left nasal fossa, which was excised. Histopathological analysis supported by immunohistochemistry confirmed high-grade SCNEC, with a Ki-67 index of 90% and diffuse expression of chromogranin and synaptophysin. Imaging demonstrated no metastatic disease, and the tumor was staged as pT1N0M0 (Stage I). The patient subsequently underwent adjuvant chemoradiotherapy beyond the initial excisional biopsy. At 12 months of follow-up, no recurrence was detected. This case highlights the importance of early detection and illustrates that organ-preserving, multimodal non-surgical management can achieve disease control in early-stage nasal SCNEC in adolescents.