Indian oncologists’ perception of the benefit of antiestrogen therapy in premenopausal women with hormone receptor positive non-metastatic breast cancer: An implementation science study.

Abstract

e18726 Background: The findings of SOFT and the TEXT trials confirm the significant benefit of deeper estrogen deprivation via ovarian function suppression (OFS) with tamoxifen (T) or aromatase inhibitors (AI) in reducing risk of recurrence in premenopausal women with hormone receptor (HR) positive breast cancer when compared with the use of tamoxifen alone. However, the decision to treat with a less or more intensive regimen is subjective to the oncologists' perception of benefit or risk. We aimed to investigate Indian oncologists' perception of benefit of various anti-estrogen therapy options in premenopausal women with high risk of recurrence. Methods: We surveyed practicing oncologists in India who treat breast cancer using a cross-sectional survey study design. We asked participants to review a clinical vignette of a young lady who was expected to have a high risk for breast cancer recurrence. We used breast cancer free interval (BCFI) as the outcome in order to compare the results of our study with the clinical trial data from SOFT and TEXT. BCFI was defined as the first occurrence of invasive loco-regional, distant or contralateral breast cancer. Oncologists were asked to designate a number between 0-100 to represent their estimation of 5-year BCFI for women with similar characteristics if they were to receive adjuvant tamoxifen with or without OFS or aromatase inhibitor with OFS. Results: 74 oncologists completed the survey. Indian oncologists estimated the 5-year BCFI for the patient in the vignette at 75.7% with the combined use of aromatase inhibitors and OFS against 64.6% with tamoxifen alone regimen. The 5 years BCFI with the combined use of tamoxifen and OFS was estimated at 71.6% (Table 1). Conclusions: The estimated absolute benefit was much lower than what was found from the two adjuvant OFS trials. An analysis of these trials have shown that patients with high recurrence risk may have an absolute benefit of 10-15% on 5-year BCFI with the use of aromatase inhibitor and OFS compared with tamoxifen alone. The oncologists in our study underestimated the benefit of such an approach. Oncologists' underestimation of the benefit of antiestrogen therapy can have significant detrimental outcomes in the management of young women diagnosed with breast cancer. We believe that such implementation science studies will help close the gap between 'what we know' and 'what we do' as physicians. [Table: see text]