t(3;8) as the sole chromosomal abnormality in a myoepithelial carcinoma ex pleomorphic adenoma: a putative progression event.

Abstract

Carcinoma ex pleomorphic adenoma (Ca ex-PA) is defined as a carcinoma arising from a primary (de novo) or recurrent benign pleomorphic adenoma (PA). We present a parotid myoepithelial carcinoma ex pleomorphic adenoma in a 38-year-old man with a t(3;8)(p21;q13) as the only chromosomal alteration by cytogenetic and spectral karyotypic analysis (SKY). The finding of this translocation in a subset of PA and in the present case suggests a critical role for this event in the malignant transformation of PA. Collectively, both the cytogenetic and the molecular studies suggest the concept that PA lacking alterations pursue a benign behavior, whereas those with the t(3;8) translocation may progress to carcinoma.