title: Impact of concurrent versus sequential tamoxifen with radiation therapy in early-stage breast cancer patients undergoing breast conservation treatment.
abstract: OBJECTIVE
  To assess the impact of sequencing of tamoxifen and radiation therapy (RT) on outcomes in early-stage breast cancer.
  
  
  METHODS
  This retrospective study evaluates the effect of the sequence of tamoxifen with RT on outcomes in stage I to II breast cancer patients who underwent breast-conservation treatment (BCT) and received adjuvant tamoxifen, with or without adjuvant chemotherapy. Patients were grouped as concurrent (tamoxifen given during RT followed by continued tamoxifen; 174 patients) and sequential (RT followed by tamoxifen; 104 patients).
  
  
  RESULTS
  Median follow-up after RT was 8.6 years for both groups. The pathologic T and N stage, race, estrogen and progesterone status, number of positive nodes, and RT were comparable between the two groups (all P >/= .08). More women age 49 years or younger and women who received chemotherapy were in the sequential group than the concurrent group (6% and 25%, respectively; P < .0001). The sequence of tamoxifen therapy did not influence 10-year local recurrence rates (sequential, 7%; concurrent, 3%; P = .52), overall survival (sequential, 86%; concurrent, 81%; P = .64), or relapse-free survival (sequential, 76%; concurrent, 85%; P = .35). When adjusting age and chemotherapy use in the multivariable Cox model, hazard ratios comparing sequential versus concurrent tamoxifen therapy were 1.56 (95% CI, 0.87 to 2.79), 1.23 (95% CI, 0.63 to 2.41), and 1.22 (95% CI, 0.33 to 4.49) for the overall survival, relapse-free survival, and local recurrence, respectively.
  
  
  CONCLUSIONS
  The therapeutic regimens of tamoxifen given concurrently or sequentially with RT both appear to be reasonable options for patients treated with BCT.
authors.affiliation: Department of Radiaton Oncology, Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, 3400 Spruce St, Philadelphia, PA 19104, USA. harris@xrt.upenn.edu
authors.forename: Eleanor E R
authors.initials: EE
authors.lastname: Harris
authors.forename: Vasthi J
authors.initials: VJ
authors.lastname: Christensen
authors.forename: Wei-Ting
authors.initials: WT
authors.lastname: Hwang
authors.forename: Kevin
authors.initials: K
authors.lastname: Fox
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Solin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D001943:Breast Neoplasms / Q000401:mortality / Q000532:radiotherapy / Q000628:therapy*; D017024:Chemotherapy, Adjuvant; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015412:Mastectomy, Segmental; D008875:Middle Aged; D011878:Radiotherapy / Q000379:methods; D012189:Retrospective Studies; D015996:Survival Rate; D013629:Tamoxifen / Q000008:administration & dosage*; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D013629:Tamoxifen