Tamoxifen use in patients with ductal carcinoma in situ and T1a/b N0 invasive carcinoma.

Background: The purpose of this study was to determine how often patients with ductal carcinoma in situ and T1a/b N0 cancer are offered and accept tamoxifen for secondary chemoprevention.

Study Design: A retrospective review of 284 patients with T1a/b N0 invasive cancer treated between February 1995 and December 2001 and 129 patients with DCIS treated after September 1998 was carried out. Patient and tumor characteristics associated with being offered and accepting tamoxifen were compared.

Results: Tamoxifen was offered to 67% of the invasive cancer patients and accepted by 76% (51% of the entire group). Hormone receptor status was the only significant predictor of being offered tamoxifen (p = 0.004). Older age (p = 0.04), Caucasian race (p = 0.01), and parity (p = 0.04) in premenopausal women were significant predictors of tamoxifen acceptance on univariate analysis. After the publication of the National Surgical Adjuvant Breast and Bowel Project P-1 trial, significantly more patients were offered tamoxifen (p = 0.02), but acceptance rates did not change. Tamoxifen was offered to 91% of the ductal carcinoma in situ patients and accepted by 73% (67% overall). Lumpectomy was associated with significantly higher rates of being offered (p = 0.02) and accepting tamoxifen (p = 0.002) on univariate analysis.

Conclusions: Factors associated with tamoxifen risks and benefits correlate poorly with the use of the drug.