Partial PTEN deletion is linked to poor prognosis in breast cancer.

Background: Deletions of chromosome 10q23, including the PTEN (phosphatase and tensin homolog) locus, are known to occur in breast cancer, but systematic analyses of its clinical relevance are lacking.

Methods: We thus analyzed a tissue microarray (TMA) with 2,197 breast cancers by fluorescence in-situ hybridization (FISH) using a PTEN-specific probe.

Results: PTEN deletions were detected in 19% of no special type, 9% of lobular, 4% of tubular cancers and 46% in carcinomas with medullary features.

8p deletion is strongly linked to poor prognosis in breast cancer.

Deletions of chromosome 8p occur frequently in breast cancers, but analyses of its clinical relevance have been limited to small patient cohorts and provided controversial results. A tissue microarray with 2,197 breast cancers was thus analyzed by fluorescence in-situ hybridization using an 8p21 probe in combination with a centromere 8 reference probe. 8p deletions were found in 50% of carcinomas with no special type, 67% of papillary, 28% of tubular, 37% of lobular cancers and 56% of cancers with medullary features.