Prognosis is worse when bilateral breast Ca develops within 5 years of the first cancer

Younger women diagnosed with bilateral breast cancer within 5 years after their first cancer diagnosis have more than triple the risk of death than unilateral breast cancer patients, whereas women developing a second cancer after 10 years have a similar prognosis to unilateral breast cancer patients, researchers report in the Sept. 20 issue of the Journal of Clinical Oncology.

Mikael Hartman, MD, of Karolinska Institute in Stockholm, Sweden, and colleagues compared the incidence and mortality rates of synchronous bilateral breast cancer (diagnosed within 3 months after a first breast cancer) and metachronous bilateral breast cancer in 6,550 patients between 1970 and 2000.

The risk of synchronous breast cancer increased with age, while the risk of metachronous breast cancer decreased with age and adjuvant treatment. The risk of death for women under 50 diagnosed with bilateral cancer within 5 years was 3.9 times higher than for unilateral breast cancer patients. However, those developing a second cancer 10 or more years after the first had a prognosis similar to unilateral breast cancer.

“We found profound differences in the incidence trends and prognostic outlook between synchronous and metachronous bilateral breast cancer diagnosis at different ages,” the authors conclude.

Hartman M, Czene K, Reilly M, et al. Incidence and prognosis of synchronous and metachronous bilateral breast cancer. J Clin Oncol. 2007;25:4210-4216.