Details

Autor(en) / Beteiligte

• Katsakhyan, Levon
• LiVolsi, Virginia A
• Chalian, Ara A
• Zhang, Paul J

Titel

Giant Cell Carcinosarcoma of the Parotid Gland With a PLAG 1 Translocation in Association With a Pleomorphic Adenoma With HMGA2 Translocation: A Case Report and Fluorescence In Situ Hybridization Study

Ist Teil von

• American journal of clinical pathology, 2020-12, Vol.154 (6), p.811-815

Ort / Verlag

Chicago: Oxford University Press

Erscheinungsjahr

2020

Quelle

Oxford Journals 2020 Medicine

Beschreibungen/Notizen

• Objectives: Carcinosarcomas of the salivary gland are rare neoplasms and have been described arising de novo or in association with pleomorphic adenoma (PA). PLAG1 and HMGA2 translocations are known to occur in PAs and carcinomas ex PA but are mutually exclusive. Methods: We report a case of a carcinosarcoma in the parotid gland of a 77-year-old man with unusual anaplastic sarcomatoid giant cell morphology. Results: Microscopically, a small separate PA was found adjacent to the carcinosarcoma. By conventional notion, the PA and carcinosarcoma would be considered related, as carcinosarcomas are well known to arise from PAs (carcinosarcoma ex PA). However, fluorescence in situ hybridization (FISH) assay demonstrated PLAG1 translocation in the carcinosarcoma and HMGA2 translocation in the separate PA. Conclusions: These findings support that the carcinosarcoma likely originated from another PA with a PLAG1 translocation or de novo but not from the coexisting PA harboring a different translocation. To our knowledge, the case is the first to demonstrate PLAG1 translocation by FISH in a sarcomatous component of any parotid gland tumor, which may help better classify these tumors. In addition, multiple PAs are commonly found in the salivary gland, and to our knowledge, our case is the first to demonstrate that the same parotid gland can host PAs and PA-related tumors with different translocations. Key Words: Salivary gland tumors; Carcinosarcomas; Sarcomatoid salivary duct carcinoma ex PA; Pleomorphic adenoma; Carcinosarcoma ex pleomorphic adenoma; True malignant mixed tumor; PLAG1; HMGA2