Initiation of and adherence to tamoxifen and aromatase inhibitor therapy among elderly women with ductal carcinoma in situ

Abstract

BACKGROUND The National Surgical Adjuvant Breast and Bowel Project B35 and International Breast Cancer Intervention Studies II Ductal carcinoma In Situ (DCIS) trials showed similar treatment effects of anastrozole and tamoxifen in reducing cancer recurrence risk among DCIS patients, but the current body of literature lacks information on the five year adherence rates for these drugs from population-based studies. METHODS This study evaluated the initiation and 5-year adherence for women aged 66 to 85 years who had been diagnosed with estrogen receptor(ER)-positive DCIS between 2007 to 2011 according to the Surveillance, Epidemiology, and End Results (SEER) and Texas Cancer Registry databases linked to Medicare claims. Chi-square test, trend test and logistic regression were used to identify factors associated with treatment initiation. RESULTS There were 2,871 women with ER-positive DCIS, and approximately 45% began treatment with tamoxifen or aromatase inhibitors (AIs) within 1 year of their DCIS diagnosis. The median age was 73 years for the users and 75 years for the non-users. Women aged 66 to 70 years who underwent lumpectomy and radiation therapy were significantly more likely to initiate hormone therapy. The initiation of therapy was also significantly associated with patients’ geographic location, education, marital status, diagnosis year, and race/ethnicity. Among users, adherence decreased from 67% in the first year to 30% in the fifth year. CONCLUSIONS Initiation and adherence levels for tamoxifen or AIs among older women with ER-positive DCIS are low. Future studies should develop methods to ensure that informed discussions take place between health care providers and patients regarding hormonal therapy for cancer prevention.

Radiation therapy utilization in Medicare beneficiaries with early‐stage breast cancer

“…10 More recently, older women who underwent lumpectomy for in situ disease were also more likely to omit hormonal blockade when no adjuvant radiation was delivered. 17 They found that women were more likely to initiate hormonal blockade if they received RT, which is in line with our findings.…”

“…Although this number may appear high, it is similar to the findings of a National Cancer Data Base analysis of older women in which the omission of RT was accompanied by a 46% rate of omission of hormonal blockade . More recently, older women who underwent lumpectomy for in situ disease were also more likely to omit hormonal blockade when no adjuvant radiation was delivered . They found that women were more likely to initiate hormonal blockade if they received RT, which is in line with our findings.…”

“…Patients were treated with RT according to individual center policies. For patients continuously enrolled in Part D, hormonal blockade use after diagnosis was identified with prescription drug names . Current Procedural Terminology / Healthcare Common Procedure Coding System codes were additionally used to increase the capture of appropriate events.…”

Tamoxifen Acceptance and Adherence among Patients with Ductal Carcinoma In Situ (DCIS) Treated in a Multidisciplinary Setting

“…The use of tamoxifen by women with ER þ DCIS has proven value, both for prevention of new primaries, and for prevention of local recurrence, but its impact is mitigated by variable acceptance of tamoxifen therapy by women with DCIS and uncertainties about adherence following initial acceptance. Recent data from health systems and large databases show that the acceptance of tamoxifen therapy following local therapy for DCIS ranges from 22% to 45% (7,33,34). At our institution, a previous analysis that included 99 premenopausal women with DCIS found that tamoxifen initiation occurred in 58% (6).…”

Oral health‐related concerns, behavior, and communication with health care providers of patients with breast cancer: impact of different treatments

“…These therapies are considered either before or after surgery based on the patients’ needs. Given that nearly 75% of BCa express estrogen and/or progesterone receptors, the majority of BCa patients receive either tamoxifen or aromatase inhibitors (AIs) (e.g., anastrozole, exemestane, or letrozole) on a long term basis (5–10 years) to decrease the risk of BCa recurrence …”