A new study published in the March 15, 2006 issue of CANCER, a peer-reviewed journal of the American Cancer Society, says that the risk of a new cancer occurring in the unaffected breast in unilateral breast cancer increases to a fair degree in women diagnosed with hereditary (non-BRCA) breast cancer.

The study also says that the risk of developing the contra lateral breast cancer in women with hereditary (non-BRCA) breast cancer greatly increases \under the age of 50. This risk id at least six times that of the non-hereditary variety. The team of reserachers led by Katarina Shahedi, M.D. of the Umeå University and colleagues at the Karolinska Institute in Stockholm, Sweden, monitored 120 families and 204 women with the unilateral breast cancer, but no history of BRCA mutations. The reserachers found that the risk of developing the contra lateral breast cancer was 5.5 percent at 5 years and up to 27.3 percent at 20 years as compared to 1.9 percent at 5 years and 4.9 percent at 20 years for others without the hereditary factor. Women who were on hormone therapy had a reduced risk of developing CBC though the reason is not clear.