NEW YORK (Reuters Health) - New research points to a dramatic increase in the number of women diagnosed with the earliest stage of breast cancer in one breast who choose to have both breasts surgically removed.

The rate of so-called "contralateral prophylactic mastectomy" surgery among U.S. women with early breast cancer called ductal carcinoma in situ (DCIS) increased by 188 percent between 1998 and 2005, Dr. Todd Tuttle, from the University of Minnesota, Minneapolis, and colleagues found.

Exactly why more and more women are opting for this treatment, however, is unclear.

"The 10-year survival rate for women with DCIS is 98 percent to 99 percent," Tuttle notes in a university-issued statement. "Therefore, removal of the normal contralateral breast will not improve the excellent survival rates for this group of women. Nevertheless, many women, particularly young women, are choosing to have both breasts removed."

The findings, reported in the Journal of Clinical Oncology, stem from a study of 51,030 women who had one-sided DCIS. Overall, 2072 women chose breast removal surgery for their cancer, the report indicates.

Among all surgically treated patients, the contralateral mastectomy rate climbed from 2.1 percent to 5.2 percent (148 percent) between 1998 and 2005.

For those treated with mastectomy, the rate of double mastectomy increased from 6.4 percent to 18.4 percent (188 percent).

More studies are "critically needed" to evaluate the complex decision-making processes leading to contralateral prophylactic mastectomy," the investigators conclude.

SOURCE: Journal of Clinical Oncology, March 20, 2009.

• More News on Breast Cancer
• More News on Mastectomy

Related MedlinePlus Pages:

• Breast Cancer
• Mastectomy