Comparative study of the efficacy of tamoxifen and aromatase inhibitors among breast cancer patients at Kenyatta National Hospital.

BACKGROUND

Aromatase inhibitors have demonstrated superior outcomes compared to tamoxifen in various studies. However, research in Africa, including Kenya, where breast cancer mortality rates are disproportionately high, is lacking.

OBJECTIVES

The study aimed to assess the comparative efficacy of tamoxifen and aromatase inhibitors among hormone receptor-positive breast cancer patients at Kenyatta National Hospital.

METHODS

A retrospective cohort study was conducted at the Oncology Department of Kenyatta National Hospital, involving all eligible hormone receptor-positive breast cancer patients treated in the facility between 1st January 2019 to 31st December 2022. The study was hospital-based and used a data abstraction tool to collect data from the patients' medical records. The data obtained was then analyzed using SPSS version 25 and Kaplan-Meier analysis was used to estimate the median survival time. Cox regression analysis was employed to determine whether there was a significant association between the variables. The collected data was presented in the form of frequency tables and graphs.

RESULTS

In our study, aromatase inhibitors consistently demonstrated superior outcomes compared to tamoxifen across various parameters. Specifically, aromatase inhibitors showed a lower incidence of disease progression (24% vs. 29.7%), a higher rate of complete radiological response (24% vs. 13.5%), and a reduced likelihood of developing distant metastasis while on treatment, coupled with a lower mortality rate (40% vs. 48.0%). Additionally, the median survival time for patients receiving aromatase inhibitors was notably longer at 49.0 months compared to 42.0 ± 3.6 months for those on tamoxifen (P = 0.410). Similarly, the aromatase inhibitor group exhibited a more extended median metastasis-free survival time (42.0 months vs. 30.0 ± 1.4 months, P = 0.056) and a more favorable survival time from metastasis to death (8 ± 0.6 months vs. 6 ± 0.8 months in the tamoxifen group, P = 0.142).

CONCLUSION

These findings collectively suggest a consistent trend towards improved treatment outcomes with aromatase inhibitors compared to tamoxifen. The observed reduction in mortality rates among aromatase inhibitor-treated patients highlights their potential clinical benefit, with superior overall survival and disease progression.