8th International Conference on Primary Therapy of Early Breast Cancer, St Gallen, Switzerland Original Article The risk of a contralateral breast cancer among women diagnosed with ductal and lobular breast carcinoma in situ: data from the Connecticut Tumor Registry*1 Elizabeth B. Claus, , 1, Meredith Stowe1, Darryl Carter2 and Theodore Holford1 1 Department of Epidemiology and Public Health, USA 2 Department of Pathology, Yale University School of Medicine, P.O. Box 3333, New Haven, CT 06510, USA Abstract Background: Women diagnosed with breast carcinoma in situ are at increased risk for developing a contralateral breast cancer. The magnitude of this risk and the relationship between this risk and age, time since diagnosis, histologic subtype, and treatment for the first breast cancer is continuing to be defined. Methods: The risk of developing a contralateral breast cancer is examined among 4198 women diagnosed with breast carcinoma in situ and reported to the Connecticut Tumor Registry (CTR) between January 1, 1975 and March 14, 1998 using Kaplan–Meier estimation. A Cox proportional hazards model is used to assess the effect of surgical treatment, radiation therapy, age at diagnosis, race, histology, marital status, anatomic location within the breast, and time since diagnosis upon this risk. Results: The cumulative 5- and 10-year probabilities of being diagnosed with a contralateral breast cancer among women initially diagnosed with a ductal breast carcinoma in situ (DCIS) were 4.3% (95% confidence interval, 3.6–5.0%) and 6.8% (95% confidence interval, 5.5–8.2%), respectively. These risks are 3.35 times greater than those for women without a history of breast cancer but are similar to those for women diagnosed with non-metastatic invasive ductal carcinomas of the breast. The cumulative 5- and 10-year probabilities of being diagnosed with a contralateral breast cancer among women initially diagnosed with a lobular breast carcinoma in situ (LCIS) were 11.9% (95% confidence interval, 9.5–14.3%) and 13.9% (95% confidence interval, 11.0–16.8%), respectively. Conclusions: Women diagnosed with LCIS were 2.6 (95% confidence interval, 2.0–3.4%) times more likely than women with DCIS to be diagnosed with a contralateral breast cancer within the first six months of the first breast primary. The risk of developing a contralateral breast cancer more than 6 months after the initial breast cancer was independent of surgical or radiation therapy, time since diagnosis, age at diagnosis, histology, race, marital status, or anatomic location of the cancer within the breast. The Breast Volume 12, Issue 6 , December 2003, Pages 451-456 Corresponding author. Address correspondence to: Dr Claus, Department of Epidemiology and Public Health, Yale University School of Medicine, 60 College Street, P.O. Box 208034, , New Haven, CT 06520-8034, , USA Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.