Women commencing anastrozole, letrozole or tamoxifen for early breast cancer: The impact of comorbidity and demographics on initial choice
MetadataShow full item record
Background: Australian clinical guidelines recommend endocrine therapy for all women with hormone-dependent early breast cancer. Guidelines specify tamoxifen as first-line therapy for pre-menopausal women, and tamoxifen or an aromatase inhibitor (AI) for post-menopausal women depending on the risk of recurrence based on tumour characteristics including size. Therapies have different side effect profiles; therefore comorbidity may also influence choice. We examined comorbidity, and the clinical and demographic characteristics of women commencing different therapies. Patients and Methods: We identified the first dispensing of tamoxifen, anastrozole or letrozole for women diagnosed with invasive breast cancer in the 45 and Up Study from 2004-2009 (N = 1266). Unit-level pharmacy and medical service claims, hospital, Cancer Registry, and self-reported data were linked to determine menopause status at diagnosis, tumour size, age, comorbidities, and change in subsidy restrictions. Chi-square tests and generalised regression models were used to compare the characteristics of women commencing different therapies. Results: Most pre-menopausal women commenced therapy with tamoxifen (91%). Anastrozole was the predominant therapy for post-menopausal women (57%), followed by tamoxifen (28%). Women with osteoporosis were less likely to commence anastrozole compared with tamoxifen (anastrozole RR = 0.7, 95% CI = 0.5-0.9). Women with arthritis were 1.6- times more likely to commence letrozole than anastrozole (95% CI = 1.1-2.1). Tamoxifen was more often initiated in women with tumours > 1 cm, who were also =75 years. Subsidy restriction changes were associated with substantial increases in the proportion of women commencing AIs (anastrozole RR = 4.3, letrozole RR = 8.3). Conclusions: The findings indicate interplay of comorbidity and therapy choice for women with invasive breast cancer. Most post-menopausal women commenced therapy with anastrozole; however, letrozole and tamoxifen were more often initiated for women with comorbid arthritis and osteoporosis, respectively. Tamoxifen was also more common for women with tumours > 1 cm and aged =75 years. Subsidy restrictions appear to have strongly influenced therapy choice. © 2014 Kemp et al.
Showing items related by title, author, creator and subject.
Kemp, A.; Preen, D.; Saunders, C.; Boyle, F.; Bulsara, M.; Malacova, Eva; Roughead, E. (2014)Purpose: Despite evidence supporting at least five years of endocrine therapy for early breast cancer, many women discontinue therapy early. We investigated the impact of initial therapy type and specific comorbidities ...
Thompson, B.; Baade, P.; Coory, M.; Carrière, P.; Fritschi, Lin (2008)Background: Australian women with early breast cancer should be given the choice between breast-conserving surgery (BCS) or mastectomy. This is the first Australian study to report on patterns of surgical care specifically ...
Night shift work and breast cancer: a pooled analysis of population-based case–control studies with complete work historyCordina-Duverger, E.; Menegaux, F.; Popa, A.; Rabstein, S.; Harth, V.; Pesch, B.; Brüning, T.; Fritschi, Lin; Glass, D.; Heyworth, J.; Erren, T.; Castaño-Vinyals, G.; Papantoniou, K.; Espinosa, A.; Kogevinas, M.; Grundy, A.; Spinelli, J.; Aronson, K.; Guénel, P. (2018)© 2018 Springer Science+Business Media B.V., part of Springer Nature Night shift work has been suspected to increase breast cancer risk but epidemiological studies have been inconsistent due to heterogeneous assessment ...