Effectiveness of switching from adjuvant tamoxifen to anastrozole in postmenopausal women with hormone-sensitive early-stage breast cancer: a meta-analysis

Jonat, W.; Gnant, Michael; Boccardo, Francesco; Kaufmann, M.; Rubagotti, Alessandra; Zuna, I.; Greenwood, Mike; Jakesz, R.

doi:10.1016/s1470-2045(06)70948-2

Cited by 229 publications

(122 citation statements)

References 22 publications

Supporting

Mentioning

114

Contrasting

Unclassified

Order By: Relevance

“…Where under-reporting is considered a potential source of bias, CLBC is probably more likely to be under-reported in trial datasets than IBTR, so this is unlikely to account for the excess of CLBC compared to ipsilateral NP. Although adjuvant systemic therapies, including endocrine and cytotoxic therapies, reduce the incidence of new primary tumors (14,31), there is no a priori reason to think that this effect will be greater on the ipsilateral than on the contralateral breast. Finally, although the risk of CLBC is increased after radiotherapy, there is no reason to believe that this risk is proportionately greater than the risk of radiation-induced cancers in the ipsilateral breast.…”

Section: Discussionmentioning

confidence: 99%

Ipsilateral Breast Tumor Relapse: Local Recurrence Versus New Primary Tumor and the Effect of Whole-Breast Radiotherapy on the Rate of New Primaries

Gujral

Sumo

Owen³

et al. 2011

International Journal of Radiation Oncology*Biology*Physics

View full text Add to dashboard Cite

Purpose: The justification for partial breast radiotherapy after breast conservation surgery assumes that ipsilateral breast tumor relapses (IBTR) outside the index quadrant are mostly new primary (NP) tumors that develop despite radiotherapy. We tested the hypothesis that whole-breast radiotherapy (WBRT) is ineffective in preventing NP by comparing development rates in irradiated and contralateral breasts after tumor excision and WBRT. Methods and Materials: We retrospectively reviewed 1,410 women with breast cancer who were entered into a prospective randomized trial of radiotherapy fractionation and monitored annually for ipsilateral breast tumor relapses (IBTR) and contralateral breast cancer (CLBC). Cases of IBTR were classified into local recurrence (LR) or NP tumors based on location and histology and were subdivided as definite or likely depending on clinical data. Rates of ipsilateral NP and CLBC were compared over a 15-year period of follow-up. Results: At a median follow-up of 10.1 years, there were 150 documented cases of IBTR: 118 (79%) cases were definite or likely LR; 27 (18%) cases were definite or likely NP; and 5 (3%) cases could not be classified. There were 71 cases of CLBC. The crude proportion of definite-plus-likely NP was 1.9% (27/1,410) patients compared with 5% (71/1,410) CLBC patients. Cumulative incidence rates at 5, 10, and 15 years were 0.8%, 2.0%, and 3.5%, respectively, for definite-plus-likely NP and 2.4%, 5.8%, and 7.9%, respectively for CLBC, suggesting a difference in the rates of NP and CLBC. Conclusions: This analysis suggests that WBRT reduces the rate of ipsilateral NP tumors. The late presentation of NP has implications for the reporting of trials that are testing partial breast radiotherapy. Ó 2011 Elsevier Inc.Breast cancer, Ipsilateral, Contralateral, Relapse, Radiotherapy.

show abstract

Section: Discussionmentioning

confidence: 99%

Ipsilateral Breast Tumor Relapse: Local Recurrence Versus New Primary Tumor and the Effect of Whole-Breast Radiotherapy on the Rate of New Primaries

Gujral

Sumo

Owen³

et al. 2011

International Journal of Radiation Oncology*Biology*Physics

View full text Add to dashboard Cite

show abstract

“…Tamoxifen, a selective estrogen receptor modulator, was the standard of care for such patients for nearly 20 years; it can significantly reduce recurrence and breast cancer-related death in patients prescribed about 5 years of adjuvant treatment [1]. However, the third-generation aromatase inhibitors (AIs) anastrozole, letrozole, and exemestane have proven more effective than tamoxifen at improving disease-free survival (DFS), whether given as upfront (initial) adjuvant therapy, as sequential or switch therapy following approximately 2-3 years of prior tamoxifen, or as extended adjuvant therapy following 5 years of tamoxifen treatment [2][3][4][5][6][7][8].…”

Section: Introductionmentioning

confidence: 99%

“…One of the primary unresolved considerations is whether these drugs should be used instead of tamoxifen as initial adjuvant treatment for postmenopausal women with successfully resected EBC, or whether 2-3 years of tamoxifen should precede the implementation of AI therapy. The latter strategy, using either exemestane [Intergroup Exemestane Study (IES)] or anastrozole (Arimidex Nolvadex [ARNO] 95 study and others) as endocrine therapy following 2-3 years of tamoxifen, potentially offers treatment cost savings relative to upfront AIs and significant improvements in DFS, event-free survival (EFS), and overall survival (OS) relative to tamoxifen alone [5][6][7]11]. A significant caveat of the switching approach is that it effectively ''misses'' a sizable number of women who may relapse during the initial treatment period with tamoxifen; these patients have been excluded from AI switching trials such as the IES and ARNO 95 [5,11].…”

Section: Introductionmentioning

confidence: 99%

Patterns and predictors of early recurrence in postmenopausal women with estrogen receptor-positive early breast cancer

Mansell

Monypenny

Skene

et al. 2008

Breast Cancer Res Treat

View full text Add to dashboard Cite

Previous studies suggest that disease recurrence peaks at around 2 years in patients with early stage breast cancer (EBC), but provide no data regarding recurrence type. This retrospective analysis aimed to identify early recurrence types and risk factors in estrogen receptor-positive (ER?) EBC patients treated with adjuvant tamoxifen following breast cancer surgery. Postmenopausal women diagnosed with ER? EBC from 1995 to 2004 were evaluated. Annual hazard ratios (HR) for recurrence at different sites were calculated. Time-dependent Cox regression analysis was used to identify predictors of recurrence within 2.5 years of diagnosis, including factors that were more strongly predictive of early than later recurrence. Of 3,614 patients evaluated, 476 developed recurrence during the 5-year median follow-up. Cumulative recurrence rates at 2.5 years (95% confidence interval) were: overall 6.3% (5.5-7.1), locoregional 1.1% (0.7-1.5), contralateral 0.5% (0.3-0.7), and distant 4.8% (4.0-5.6). The annual HR of overall recurrence peaked at 2 years (4.3% per annum).The majority of this peak represented distant recurrence (3.4% per annum). In Cox regression analysis, tumor size and grade, lymph node involvement, lymphovascular invasion, and symptomatic presentation were significant independent predictors of early recurrence. Age at diagnosis was independently predictive of recurrence within 2.5 years of diagnosis but not later recurrence. This study identified an early recurrence peak at 2 years, most of which were distant recurrences. Implementing an aromatase inhibitor after an initial 2-3 years of tamoxifen fails to address this early peak of distant recurrence and the potential breast cancer-associated mortality.

show abstract

“…Although aromatase inhibitors do prolong disease-free survival compared to tamoxifen [3], tamoxifen still has a major role in breast cancer treatment [4]. In addition, a survival benefit has been shown for sequential tamoxifen and an aromatase inhibitor [5,6]. A molecular test helping clinicians to make a choice between starting with either tamoxifen, an aromatase inhibitor or rather with chemotherapy would have enormous potential for tailoring treatment.…”

Section: Introductionmentioning

confidence: 99%

Comparison of gene expression profiles predicting progression in breast cancer patients treated with tamoxifen

Kok

Linn

Laar

et al. 2008

Breast Cancer Res Treat

View full text Add to dashboard Cite

Effectiveness of switching from adjuvant tamoxifen to anastrozole in postmenopausal women with hormone-sensitive early-stage breast cancer: a meta-analysis

Cited by 229 publications

References 22 publications

Ipsilateral Breast Tumor Relapse: Local Recurrence Versus New Primary Tumor and the Effect of Whole-Breast Radiotherapy on the Rate of New Primaries

Ipsilateral Breast Tumor Relapse: Local Recurrence Versus New Primary Tumor and the Effect of Whole-Breast Radiotherapy on the Rate of New Primaries

Patterns and predictors of early recurrence in postmenopausal women with estrogen receptor-positive early breast cancer

Comparison of gene expression profiles predicting progression in breast cancer patients treated with tamoxifen

Contact Info

Product

Resources

About