title: Impact of randomized clinical trial results in the national comprehensive cancer network on the use of tamoxifen after breast surgery for ductal carcinoma in situ.
abstract: OBJECTIVE
  The National Surgical Adjuvant Breast and Bowel Project B-24 trial, published in June 1999, demonstrated that tamoxifen after breast-conserving surgery (BCS) and radiotherapy for ductal carcinoma in situ (DCIS) reduced the absolute occurrence of ipsilateral and contralateral breast cancer. We assessed the impact of B-24 on practice patterns at selected National Comprehensive Cancer Network (NCCN) centers.
  
  
  METHODS
  Tamoxifen use after surgery was examined among 1,622 patients presenting for treatment of unilateral DCIS between July 1997 and December 2003 at eight NCCN centers. Associations of clinicopathologic and treatment factors with tamoxifen use were assessed in univariate and multivariable logistic regression analyses.
  
  
  RESULTS
  Overall, 41% of patients (665 of 1,622) received tamoxifen. The proportion increased from 24% before July 1, 1999, to 46% on or after July 1, 1999. Factors significantly associated with receipt of tamoxifen included diagnosis on or after July 1, 1999 (odds ratio [OR], 3.85; P < .0001), BCS in patients younger than 70 years (OR, 3.21; P = .0073), no history of cerebrovascular or peripheral vascular disease (OR, 3.13; P = .0071), receipt of radiotherapy (OR, 1.82; P = .0009), and previous hysterectomy (OR, 1.34; P = .0459). Tamoxifen use varied significantly by center, from 34% to 74% after BCS and 17% to 53% after mastectomy (P < .0001).
  
  
  CONCLUSIONS
  Tamoxifen use after surgery for DCIS at NCCN centers increased after presentation of the B-24 results. Rates varied substantially by institution, suggesting that physicians differ in how they weigh the modest reduction in breast cancer risk with tamoxifen against its potential adverse effects in this population.
authors.affiliation: Department of Surgical Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX, USA. tyen@mcw.edu
authors.forename: Tina W F
authors.initials: TW
authors.lastname: Yen
authors.forename: Henry M
authors.initials: HM
authors.lastname: Kuerer
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: Ottesen
authors.forename: Layla
authors.initials: L
authors.lastname: Rouse
authors.forename: Joyce C
authors.initials: JC
authors.lastname: Niland
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Edge
authors.forename: Richard L
authors.initials: RL
authors.lastname: Theriault
authors.forename: Jane C
authors.initials: JC
authors.lastname: Weeks
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000601:surgery; D002278:Carcinoma in Situ / Q000188:drug therapy* / Q000601:surgery; D018270:Carcinoma, Ductal, Breast / Q000188:drug therapy* / Q000601:surgery; D017024:Chemotherapy, Adjuvant; D003131:Combined Modality Therapy; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010818:Practice Patterns, Physicians'; D016032:Randomized Controlled Trials as Topic; D013629:Tamoxifen / Q000627:therapeutic use*; D014481:United States
chemical_list: D018931:Antineoplastic Agents, Hormonal; D013629:Tamoxifen