A Challenging Diagnosis of Laryngeal Neuroendocrine Tumor (NET): Final Classification as NET Grade 3 After Total Laryngectomy.

Laryngeal neuroendocrine neoplasms (NENs) are rare tumors that account for a small proportion of all laryngeal malignancies. They exhibit a wide range of differentiation and proliferative activity, and are often graded accordingly, using markers such as mitotic count and Ki-67 labeling index. We present the case of a 76-year-old man with progressive dysphagia and a supraglottic mass. Initial biopsy findings were inconclusive, raising suspicion of poorly differentiated carcinoma or metastatic disease. A re-biopsy of the larynx under general anesthesia and neck dissection revealed features consistent with neuroendocrine tumor (NET) Grade 2 (Ki-67 index 17%). Due to the limited efficacy of nonsurgical treatments and absence of somatostatin receptor expression, total laryngectomy was performed. Histopathological analysis of the resected specimen demonstrated increased mitotic activity and a Ki-67 index of 28%, leading to a revised diagnosis of NET Grade 3. This case highlights the diagnostic limitations of small biopsy specimens in the head and neck region and underscores the importance of stepwise evaluation, including surgical pathology, in establishing an accurate diagnosis and guiding curative treatment decisions in rare laryngeal NETs.