- Largest Genomic Study Comparing Gene Expression in Female and Male Patients Presented at ASCO Annual Meeting -

ORLANDO, Fla., May 29 /PRNewswire-FirstCall/ -- Genomic Health, Inc. (Nasdaq: GHDX) today announced results from a study which summarized the gene signatures identified by the Oncotype DX(R) breast cancer test in a large number of male patients for whom the test was used to guide treatment with chemotherapy. The results, which will be presented in a poster presentation on Monday, June 1 (1:00 - 5:00 p.m. ET) at the American Society of Clinical Oncology (ASCO) annual meeting in Orlando, demonstrated that breast cancer in men displays similar gene signatures to female breast cancer.

'Breast cancer is not just a woman's disease, yet treatment for men is typically extrapolated from our experience in the female population since it is rare and there is little known about the biology of male breast cancer,' said George Sledge, M.D., Ballve-Lantero Professor of Oncology at Indiana University in Indianapolis, and lead investigator of the study. 'This is the largest genomic study to compare gene expression in female and male patients, and results support the clinical utility of Oncotype DX in providing quantitative information to help guide treatment decisions for men with breast cancer.'

The study, 'Molecular characterization of male breast cancer by standardized quantitative RT-PCR analysis: First large genomic study of 347 male breast cancers compared to 82,434 female breast cancers' (Abstract #549), analyzed quantitative gene expression by gender status in estrogen receptor (ER) positive tumor specimens. As with female breast cancer, a wide inter-patients variation was observed in gene expression in male breast cancer. The proportion of tumors with low risk of recurrence based on the Recurrence Score(R) was 53.6 percent in males versus 53.4 percent in females, intermediate risk of recurrence was 35.2 percent in males versus 36.3 percent in females, and high risk of recurrence was 11.2 percent in males versus 10.3 percent in females.

Despite the similarities between the two patient groups, there were also some differences. For example, male breast cancer patients had higher mean expression of the hormone receptor genes, likely due to the different hormonal context of men and women. In addition, male breast cancer patients were older, on average, and were less likely than women to have the lobular form of breast cancer.

'I was quite surprised when my doctor told me I had breast cancer and was not looking forward to the multiple rounds of chemotherapy that he originally recommended,' said Mike Nelsen, a breast cancer patient from Baltimore.