Health-related quality-of-life and psychological distress of postmenopausal breast cancer patients after surgery during the randomized trial, N-SAS BC 03, comparing further tamoxifen with switching to anastrozole after adjuvant tamoxifen for 1 to 4 years: the final results

Abstract #1136 Backgroud: Three years ago, we reported the interim results regarding heath-related quality of life (HRQOL) outcomes of the patients who switched their adjuvant endocrine therapy from several years of tamoxifen (TAM) to anastrozole (ANA) and those who had TAM for a total of 5 years in the randomized trial, National Surgical Adjuvant Study of Breast Cancer (NSAS BC) 03. We present the final results of HRQOL and psychological distress in the NSAS BC 03. Patients and Methods: Recurrence-free postmenopausal breast cancer patients who had received definitive surgery for hormone receptor positive breast cancer, and had been taking TAM for 1 to 4 years after the surgery were enrolled in the randomized trial: N-SAS BC 03. They were randomly assigned to continue TAM for the remaining periods of a total of 5 years or to switch from TAM to ANA and take the latter for the remaining periods. Primary endpoints of the N-SAS BC 03 trial were disease-free survival and adverse events. HRQOL and psychological distress were evaluated as secondary endpoints. They were asked to answer patient-administered instruments to assess HRQOL (FACT-B [breast cancer scale] and FACT-ES [endocrine symptom scale]) and psychological distress (CES-D: Center for Epidemiologic Studies Depression scale) at the randomization (baseline), 3 months, 1 and 2 years after the randomization. HRQOL and psychological distress scores during this period were compared using t-test and the general linear model with correlated errors. Results: There was no difference in demographic and medical characteristics between the two treatment groups. The response rates of the questionnaires were 98.6%, 97.2%, 90.9% and 78.5% at baseline, 3 months, 1 and 2 years after the randomization, respectively. At baseline 694 patients (346 in the TAM group and 348 in the ANA group) answered them. The total scores of FACT-G, and FACT-ES and the scores of FACT-G physical well-being (PWB) subscale were statistically significantly better in the TAM group than in the ANA group (P = 0.042, 0.038, and 0.005, respectively) after the randomization, while those of FACT-B in the former were marginally better than those in the latter (P= 0.066). However, there were no statistically significant differences between the two treatment groups for the scores of CES-D, and subscales other than PWB of FACT-G, FACT-B, and FACT-ES. Conclusions: Further TAM treatment after adjuvant TAM for 1 to 4 years may provide postmenopausal breast cancer patients with slightly better HRQOL comparing with switching to ANA. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1136.