Retrospective analysis of time to recurrence in the ATAC trial according to hormone receptor status: an hypothesis-generating study.
dc.contributor.author | Dowsett, Mitch | |
dc.contributor.author | Cuzick, Jack | |
dc.contributor.author | Wale, Chris | |
dc.contributor.author | Howell, Anthony | |
dc.contributor.author | Houghton, Joan | |
dc.contributor.author | Baum, Michael | |
dc.date.accessioned | 2009-08-10T09:20:28Z | |
dc.date.available | 2009-08-10T09:20:28Z | |
dc.date.issued | 2005-10-20 | |
dc.identifier.citation | Retrospective analysis of time to recurrence in the ATAC trial according to hormone receptor status: an hypothesis-generating study. 2005, 23 (30):7512-7 J. Clin. Oncol. | en |
dc.identifier.issn | 0732-183X | |
dc.identifier.pmid | 16234518 | |
dc.identifier.doi | 10.1200/JCO.2005.01.4829 | |
dc.identifier.uri | http://hdl.handle.net/10541/76796 | |
dc.description.abstract | PURPOSE: Arimidex, tamoxifen alone, or in combination (ATAC) trial of anastrozole (Arimidex) versus tamoxifen or a combination of the two in 9,366 postmenopausal patients with primary breast cancer found a significant improvement in disease-free survival and time to recurrence (TTR) for anastrozole compared with tamoxifen, that was restricted to patients with hormone receptor-positive (ie, estrogen receptor-positive [ER+] and/or progesterone receptor-positive [PgR+]) disease, the target population for these therapies. We retrospectively tested the hypothesis that this benefit might differ according to PgR status. PATIENTS AND METHODS: TTR was compared between the three treatment groups for subgroups defined by ER and PgR status using Cox's proportional hazards model, with and without adjustment for baseline variables. RESULTS: The unadjusted hazard ratio (HR) for anastrozole versus tamoxifen for TTR was 0.74 (95% CI, 0.64 to 0.87) for women with either ER+ or PgR+ tumors. In the ER+/PgR+ subgroup (n = 3,834) the HR was 0.84 (95% CI, 0.69 to 1.02) compared with 0.43 (95% CI, 0.31 to 0.61) in the ER+/PgR-negative (PgR-) subgroup (n = 880). In the adjusted model the HRs were 0.83 and 0.45, respectively. CONCLUSION: Time to recurrence was longer for anastrozole- than tamoxifen-treated patients in both ER+/PgR+ and ER+/PgR- subgroups, but the benefit was substantially greater in the PgR- subgroup. As this was an "exploratory" analysis, this effect should be considered as hypothesis generating and assessed prospectively in other trials comparing the adjuvant use of an aromatase inhibitor with tamoxifen. | |
dc.language.iso | en | en |
dc.subject | Breast Cancer | en |
dc.subject | Cancer Recurrence | en |
dc.subject.mesh | Antineoplastic Combined Chemotherapy Protocols | |
dc.subject.mesh | Breast Neoplasms | |
dc.subject.mesh | Chemotherapy, Adjuvant | |
dc.subject.mesh | Disease-Free Survival | |
dc.subject.mesh | Double-Blind Method | |
dc.subject.mesh | Female | |
dc.subject.mesh | Humans | |
dc.subject.mesh | Neoplasm Recurrence, Local | |
dc.subject.mesh | Nitriles | |
dc.subject.mesh | Postmenopause | |
dc.subject.mesh | Receptors, Estrogen | |
dc.subject.mesh | Receptors, Progesterone | |
dc.subject.mesh | Retrospective Studies | |
dc.subject.mesh | Survival Rate | |
dc.subject.mesh | Tamoxifen | |
dc.subject.mesh | Time Factors | |
dc.subject.mesh | Treatment Outcome | |
dc.subject.mesh | Triazoles | |
dc.title | Retrospective analysis of time to recurrence in the ATAC trial according to hormone receptor status: an hypothesis-generating study. | en |
dc.type | Article | en |
dc.contributor.department | Royal Marsden Hospital London, SW3 6JJ United Kingdom. mitch.dowsett@icr.ac.uk | en |
dc.identifier.journal | Journal of Clinical Oncology | en |
html.description.abstract | PURPOSE: Arimidex, tamoxifen alone, or in combination (ATAC) trial of anastrozole (Arimidex) versus tamoxifen or a combination of the two in 9,366 postmenopausal patients with primary breast cancer found a significant improvement in disease-free survival and time to recurrence (TTR) for anastrozole compared with tamoxifen, that was restricted to patients with hormone receptor-positive (ie, estrogen receptor-positive [ER+] and/or progesterone receptor-positive [PgR+]) disease, the target population for these therapies. We retrospectively tested the hypothesis that this benefit might differ according to PgR status. PATIENTS AND METHODS: TTR was compared between the three treatment groups for subgroups defined by ER and PgR status using Cox's proportional hazards model, with and without adjustment for baseline variables. RESULTS: The unadjusted hazard ratio (HR) for anastrozole versus tamoxifen for TTR was 0.74 (95% CI, 0.64 to 0.87) for women with either ER+ or PgR+ tumors. In the ER+/PgR+ subgroup (n = 3,834) the HR was 0.84 (95% CI, 0.69 to 1.02) compared with 0.43 (95% CI, 0.31 to 0.61) in the ER+/PgR-negative (PgR-) subgroup (n = 880). In the adjusted model the HRs were 0.83 and 0.45, respectively. CONCLUSION: Time to recurrence was longer for anastrozole- than tamoxifen-treated patients in both ER+/PgR+ and ER+/PgR- subgroups, but the benefit was substantially greater in the PgR- subgroup. As this was an "exploratory" analysis, this effect should be considered as hypothesis generating and assessed prospectively in other trials comparing the adjuvant use of an aromatase inhibitor with tamoxifen. |