Adherence to endocrine therapy and its relation to disease-free survival among breast cancer patients visiting an out-patient clinic at Khartoum Oncology Hospital, Sudan.

RATIONALE

Adherence to endocrine therapy provides substantial reduction in breast cancer (BC) relapses and improve survival. Hence, non-adherence remains an under reported issue mainly in developing countries.

AIMS AND OBJECTIVES

The aim of this study is to evaluate the adherence to endocrine therapy (tamoxifen [TAM] and aromatase inhibitors [AIs]) among BC patients visiting an out-patient clinic (2015-2016) in Khartoum Oncology Hospital, Sudan.

METHODS

Adherence was assessed using pills count and self-reporting methods. A total of 172 patients were interviewed. Also, records were reviewed for demographic and other cancer characteristics.

RESULTS

The patients' mean age at diagnosis was 53 years, with the highest frequency at (41-60) years. Invasive ductal carcinoma 69.2% formed the main pathological diagnosis. T2 tumour size (51.2%) and lymph node involvement (N1) (31.4%) were most evident. Also, the majority of patients were stage III (45.9%) and grade II (48%). The studied women were postmenopausal (49.4%) and premenopausal (47.7%). Regarding hormonal receptors, about 68% were oestrogen (ER)+/progesterone (PR)+ and 23.3% were ER+/PR-. Studying adherence, almost (93%) of the studied group were ≥80% adherent to TAM and AIs. The hormonal therapy persistence mean was 27.2 ± 22.5 months (40-96). While adherence percentage mean was 93.7 ± 13.6% (0%-100%). Also disease-free survival (DFS) mean was 36.3 ± 32.7 months (4-312). Adherence to hormonal therapy and persistence were significantly correlated (P < .000). Also, statistically significant association was found between hormonal therapy adherence (≥80%) and patient poor to average economic status (P = .006), and the marital status "married" (P = .008).

CONCLUSIONS

A high rate of adherence (93%) to endocrine therapy was estimated in the present study. Also, a positive association was found between the hormonal therapy persistence, and the DFS year's groups (P = .000), and the hormonal therapy types (P = .000). Adherence to hormonal therapy and persistence were significantly correlated (P < .000).