A case of primitive neuroectodermal tumor (pnet) of the larynx

Abstract

Objectives: PNET (Primitive neuroectodermal tumor) is a malignant neoplasm that originates from the cells of the primitive neural crest. PNET mainly occurs in the brain, extremities, pelvis, and the chest wall. PNET in the cerebellum is also called medulloblastoma. The peripheral PNET is part of the Ewing’s sarcoma family of tumor, which includes Ewing tumor of bone, extraosseus Ewing tumor (tumor growing outside of the bone), primitive neuroectodermal tumor (PNET), and Askin tumor (PNET of the chest wall). PNET of the larynx is extremely rare. Recently, we experienced a case of laryngeal PNET. The clinical course and findings are presented. Methods: A 14-year-old Japanese female with a 4-month history of neck swelling and a 2-week history of dyspnea was referred. Indirect laryngoscopy revealed a necrotic tumor occupied the laryngopharyngeal space. CT scan revealed a massive tumor occupied the endolarynx and multiple cervical lymph node swellings. Emergency tracheotomy and biopsies from the larynx and the cervical lymph node were done. Results: Histopathologic finding showed monotonous sheets of hyperchromatic cells with round to oval nuclei. The tumor was diagnosed as PNET. Two-series of intense chemotherapy was instilled and the laryngeal tumor disappeared. Neck dissection was done for the residual neck node swellings but there were no viable tumors remained. Conclusion: Both the laryngeal and the neck tumors showed complete response to the chemotherapy and at this point her larynx was preserved. Based on the high incidence of metastasis and recurrence, additional chemotherapy and radiation therapy is needed and will be done in the near future.