Breast disease type main predictor of tamoxifen use

A history of atypical hyperplasia (AH) or lobular carcinoma in situ (LCIS) is the main predictor of being offered and accepting the chemopreventive agent tamoxifen, new research indicates. The results, which are reported in the March 22nd online issue of Cancer, also indicate that most women offered the drug do not accept it.

This is a concerning finding, write the report’s authors, given the results of the National Surgical Adjuvant Breast and Bowel Project (NSABP) P-1 trial, which showed a 49% reduction in cancer risk for high-risk tamoxifen users. Dr. Monica Morrow and colleagues, from Northwestern University in Chicago, analyzed data from 219 women who sought risk evaluation after the release of the NSABP P-1 trial results in 1998. Overall, 137 (63%) women were offered tamoxifen, the researchers note. Of these women, only 57 (42%) actually took the drug. A variety of factors were linked with being offered tamoxifen, but on multivariate analysis the only significant predictors were a history of AH or LCIS and hysterectomy. The odds ratios for a history of AH or LCIS were 20.3 and 3.4, respectively.In terms of tamoxifen acceptance, AH or LCIS history were also significant predictors as well as older patient age. “This study provides initial data characterizing women who accept and those who refuse chemoprevention,” the authors state. “Further investigation of the differences in the perception of women at risk on the basis of histologic factors compared with those at risk because of other causes may provide the basis for improved educational strategies for chemoprevention counseling in the future.” (Source: Cancer 2004;100: Reuters Health: Oncolink)