Lower limb venous thrombosis among breast cancer patients receiving tamoxifen in Uganda

Abstract

Abstract Background Tamoxifen therapy is an effective and mainstay adjuvant treatment for estrogen-positive breast cancer patients. However, it has partial estrogen receptor agonist activity that causes hypercoagulation of blood and consequently venous thrombus formation. Patients who are being treated with tamoxifen require monitoring, because of the increased risk for developing deep venous thrombosis (DVT) and pulmonary embolism that could increase morbidity and mortality if left undiagnosed. This study sought to determine the prevalence and associated factors of lower limb DVT among breast cancer patients on tamoxifen, in Uganda. Methods This was a cross-sectional study done among patients receiving tamoxifen therapy who attended the breast clinic at the Uganda Cancer Institute. Clinical evaluation, mean platelet volume (MPV) and bilateral lower limb compression and Doppler ultrasound scans were done to screen for DVT. Univariate analysis was used to summarize continuous variables as mean and corresponding standard deviations, and categorical variables as proportions. Results Of the 180 participants, 170 (94.4%) were females, 141 (78.3%) were below 60 years. More than 95% were neither diabetic nor smokers and 163 (90.6%) of them had a BMI of < 35Kg/m2. The prevalence of DVT was 0.6%. The statistical significance of the associated factors could not be elucidated at bivariate or multivariate analysis due to the very low prevalence of DVT. Conclusion The prevalence of DVT among breast cancer patients on tamoxifen at the Uganda cancer institute was very low (0.6%). The patients with normal MPV findings are unlikely to have DVT despite the intermediate risk on clinical assessment, therefore a routine sonographic examination for younger Ugandan patients on tamoxifen may not be necessary.