Extraskeletal Myxoid Chondrosarcoma of Nasopharynx: An Oncologic Entity Rarely Reported

Abstract

Extraskeletal myxoid chondrosarcoma (ESMC) is an extremely rare variant of chondrosarcoma accounting for less than 10% cases. It affects mainly the soft tissues of the proximal end of long bones. Its incidence in the head and neck region is less than 5%. This case presented in the nasopharynx, an exceedingly unusual site for ESMC in a 60-year-old female with left-sided nasal obstruction and occasional epistaxis of one-year duration. Biopsy from the nasopharyngeal mass was suggestive of low-grade chondrosarcoma. She underwent endoscopic resection of the tumor. Postoperative histopathology confirmed the diagnosis as myxoid chondrosarcoma of nasopharynx after performing a battery of immunohistochemical markers to rule out other possible differential diagnoses. We treated her with conformal adjuvant radiotherapy to a dose of 66 Gray in 33 fractions given residual disease to which she responded well with significant symptomatic and radiological improvement. The patient has been on regular follow-up for over two years without any evidence of recurrence or distant metastasis. This case is presented to highlight the extreme rarity, the clinicopathological findings of this disease, and to emphasize the role of radiotherapy as the primary adjuvant treatment affecting the final prognosis. A thorough review of the literature reveals that our case may be the second case of myxoid chondrosarcoma of nasopharynx ever reported in the world literature to date.