Hypopharyngeal Dedifferentiated Liposarcoma in the MDM2 Era: A Case Report and Short Review

Abstract

Pharyngeal liposarcomas are very rare; still more rare are dedifferentiated liposarcomas in the pharynx. An 82-year-old man presented with dysphagia, voice changes, weight loss, nasal regurgitation of liquids, and coughing spells. A 3.5 cm mass was identified in the hypopharynx. The mass was biopsied and diagnosed as a benign fibroepithelial polyp. Continued symptoms and airway obstruction prompted a pharyngectomy, and the mass was then diagnosed as dedifferentiated liposarcoma. Due to infrequency and subtle histological findings, liposarcomas of the head and neck can be misdiagnosed and recur.

Liposarcoma of Laryngeal Vallecula

“…It is a malignant neoplasm recapitulating fat. It may recur locally but usually does not metastasize unless dedifferentiated [5,7,8].…”

“…This highlevel survival is likely because the tumor is slow-growing and tends not to metastasize; although local recurrence is common. A liposarcoma diagnosis is usually delayed because of the indolent nature of tumor, though symptoms differ according to the location and size, and patients often have no complaints in the early stage of disease [5][6][7][8][9][10].…”

“…The prognosis of laryngeal liposarcomas appears to be more favourable compared to liposarcomas affecting other regions. This feature seems to be related to the low incidence of high-grade tumours and to the rarity of metastases [3][4][5][6][7][8][9][10].…”

“…Genetic alterations are becoming increasingly recognized as causative factors and have been used to improve the accuracy of subtyping combined with morphology [4,5]. In all sites including outside the head and neck, liposarcoma is the most common tumor among sarcomas of the soft tissue and is categorized into four subgroups: atypical lipomatous tumor/well-differentiated liposarcoma (WDLS), dedifferentiated liposarcoma (DDLS), myxoid liposarcoma, and pleomorphic liposarcoma [6,7].…”

Seltene Erkrankungen der Mundhöhle, des Halses und des Pharynx

“…They are subdivided into 4 subtypes: well differentiated liposarcomas (40–45%), myxoid/round cell liposarcomas (30–35%), pleomorphic liposarcomas, and poorly differentiated liposarcomas (10%; 146 ). They mainly develop in males of higher age (mean: 7 th decade), the 5-year survival rate amounts to about 67% 206 . For histopathological differentiation between lipomas and liposarcomas, the MDM2 or CDK4 amplification is determined 4 .…”