Genetic profile of adenoid cystic carcinomas (ACC) with high-grade transformation versus solid type

Author(s)

Costa, Ana Flavia ; Altemani, Albina ; Vekony, Hedy ; Bloemena, Elisabeth ; Fresno, Florentino ; Suarez, Carlos ; Luis Llorente, Jose ; Hermsen, Mario

• Document type: Journal article
• Source: CELLULAR ONCOLOGY; v. 34, n. 4, p. 11-pg., 2011-08-01.

Abstract

ACC can occasionally undergo dedifferentiation also referred to as high-grade transformation (ACC-HGT). However, ACC-HGT can also undergo transformation to adenocarcinomas which are not poorly differentiated. ACC-HGT is generally considered to be an aggressive variant of ACC, even more than solid ACC. This study was aimed to describe the genetic changes of ACC-HGT in relation to clinico-pathological features, and to compare results to solid ACC. Genome wide DNA copy number changes were analyzed by microarray CGH in ACC-HGT, four with transformation into moderately differentiated adenocarcinoma (MDA) and two into poorly differentiated carcinoma (PDC), and five solid ACC. In addition, Ki67 index and p53 immunopositivity was assessed. ACC-HGT carried fewer copy number changes compared to solid ACC. Two ACC-HGT cases harboured a breakpoint at 6q23, near the cMYB oncogene. The complexity of the genomic profile concurred with the clinical course of the patient. Among the ACC-HGT, p53 positivity significantly increased from the conventional to the transformed (both MDA and PDC) component. ACC-HGT may not necessarily reflect a more advanced stage of tumor progression, but rather a transformation to another histological form in which the poorly differentiated forms (PDC) presents a genetic complexity similar to the solid ACC. (AU)

• FAPESP's process: 09/54377-2 - Identification of genetic and epigenetic alterations in adenoid cystic carcinoma with high-grade transformation
• Grantee: Ana Flávia de Mattos Costa
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 10/51571-0 - Identification of genetic and epigenetic alterations in adenoid cystic carcinoma with high-grade transformation
• Grantee: Albina Messias de Almeida Milani Altemani
• Support Opportunities: Regular Research Grants