To date, the impact of the National Surgical Adjuvant Breast and Bowel Project (NSABP) B-24 trial reported in 1999 on the use of tamoxifen after surgery for ductal carcinoma in situ (DCIS) is unknown. The current study was designed to evaluate the impact of NSABP B-24 on current practices at a comprehensive cancer center.
The records of 350 consecutive patients with DCIS who were treated at the authors' institution between July 1999 and June 2002 were obtained from a prospective database and analyzed. Whether patients were offered tamoxifen, whether patients accepted tamoxifen, and the associated reasons were recorded along with tamoxifen-related side effects and patient compliance with therapy. Clinical and pathologic factors were evaluated for their impact on recommendations regarding tamoxifen. Differences were assessed by chi-square analysis.
Of the 350 patients, 73 were excluded because of evidence of invasive carcinoma on final pathology review. Of the remaining 277 patients, 166 patients (60%) were offered tamoxifen, and 90 patients (54%) chose to take tamoxifen. Of 111 patients who were not offered tamoxifen, 39 patients (35%) had documented explanations, which included bilateral mastectomy (n = 25 patients), medical reasons (n = 10 patients), and already received tamoxifen for other reasons at the time of diagnosis (n = 4 patients). Of 94 patients who received tamoxifen, 20 patients (21%) discontinued use because of side effects or complications. Tamoxifen was more likely to be recommended for women who underwent segmental resection compared with women who underwent total mastectomy (P = 0.002) and for women with smaller pathologic DCIS tumors (P = 0.001). In addition, these two factors were interrelated.
Physicians and patients remain cautious regarding the use of tamoxifen after local treatment for DCIS. The current findings have implications for current trials evaluating aromatase inhibitors and other chemopreventive agents for this disease. Cancer 2004;100:942–9. © 2004 American Cancer Society.