Tamoxifen in Treatment of Intraductal Breast Cancer: National Surgical Adjuvant Breast and Bowel Project B-24 Randomised Controlled Trial

Lancet. 1999 Jun 12;353(9169):1993-2000. doi: 10.1016/S0140-6736(99)05036-9.

Abstract

Background: We have shown previously that lumpectomy with radiation therapy was more effective than lumpectomy alone for the treatment of ductal carcinoma in situ (DCIS). We did a double-blind randomised controlled trial to find out whether lumpectomy, radiation therapy, and tamoxifen was of more benefit than lumpectomy and radiation therapy alone for DCIS.

Methods: 1804 women with DCIS, including those whose resected sample margins were involved with tumour, were randomly assigned lumpectomy, radiation therapy (50 Gy), and placebo (n=902), or lumpectomy, radiation therapy, and tamoxifen (20 mg daily for 5 years, n=902). Median follow-up was 74 months (range 57-93). We compared annual event rates and cumulative probability of invasive or non-invasive ipsilateral and contralateral tumours over 5 years.

Findings: Women in the tamoxifen group had fewer breast-cancer events at 5 years than did those on placebo (8.2 vs 13.4%, p=0.0009). The cumulative incidence of all invasive breast-cancer events in the tamoxifen group was 4.1% at 5 years: 2.1% in the ipsilateral breast, 1.8% in the contralateral breast, and 0.2% at regional or distant sites. The risk of ipsilateral-breast cancer was lower in the tamoxifen group even when sample margins contained tumour and when DCIS was associated with comedonecrosis.

Interpretation: The combination of lumpectomy, radiation therapy, and tamoxifen was effective in the prevention of invasive cancer.

Publication types

  • Clinical Trial
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Antineoplastic Agents, Hormonal / adverse effects
  • Antineoplastic Agents, Hormonal / therapeutic use*
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / mortality
  • Breast Neoplasms / pathology
  • Breast Neoplasms / therapy
  • Carcinoma in Situ / drug therapy
  • Carcinoma in Situ / therapy
  • Carcinoma, Intraductal, Noninfiltrating / drug therapy*
  • Carcinoma, Intraductal, Noninfiltrating / mortality
  • Carcinoma, Intraductal, Noninfiltrating / secondary
  • Carcinoma, Intraductal, Noninfiltrating / therapy
  • Carcinoma, Lobular / drug therapy
  • Carcinoma, Lobular / therapy
  • Combined Modality Therapy
  • Double-Blind Method
  • Female
  • Humans
  • Mastectomy, Segmental
  • Middle Aged
  • Survival Rate
  • Tamoxifen / adverse effects
  • Tamoxifen / therapeutic use*

Substances

  • Antineoplastic Agents, Hormonal
  • Tamoxifen