Chemoprevention Indication Score: A user-friendly tool for prevention of breast cancer - Pilot analysis

BackgroundDespite the results of prospective randomized placebo controlled studies, endorsement from various professional societies, and approval by the FDA, the chemoprevention of breast cancer is limited. This is attributable to the perceived risks of complications with tamoxifen. Individualized risk-benefit calculation regarding the use of tamoxifen is burdensome for practical clinical use. We propose a Chemoprevention Indication Score (CIS) that is easy to compute and reliable to identify women suitable for chemoprevention.Material and methodsChart-review of all patients attending a university-based high-risk breast clinic identified the women offered chemoprevention and those who accepted it. Age, Gail risk score, past medical history and physician's reasons for not offering tamoxifen were recorded. CIS was developed weighing risks and benefits of tamoxifen; high, moderate and low indication score categories were defined for recommendation of tamoxifen. CIS was validated by cross-tabulating with the rate of physician recommendation of tamoxifen and by agreement with Gail's risk-benefit index.ResultsBetween 2004 and 2006,105 women attended the high-risk clinic. Median (interquartile) age was 47 (42-53) yrs; 142(90%) were Caucasian. Median (interquartile) Gail score was 2.3 (1.0-3.2). Forty-eight (46%) women were offered tamoxifen while 15(14%) complied. Tamoxifen was offered to 1 of 5(20%) women with low; 32 of 82(39%) women with moderate and 15 of 18(83%) women with high CIS [p = 0.0008]. The McNemar's test for agreement between CIS (<6 vs. ≥6) and Gail's risk-benefit index was significant at p < 0.0001 and Kruskal-Wallis test comparing median Gail's risk-benefit index across CIS was significant at p < 0.0001.ConclusionInability to identify appropriate candidates has been a great barrier towards acceptance of chemoprevention for breast cancer. The CIS can be used for individual risk-benefit analysis for recommendation of breast cancer chemoprevention. However, CIS needs to be validated on a larger scale with methodologically more rigorous studies before proposing generalized use in the community.