Mammography in Nigeria: A Rigorous Retrospective Analysis of One-Year Utilization in a Tertiary Hospital - Abstract
Abstract Background: Mammography screening is the most effective way to minimize breast cancer morbidity and mortality. Unfortunately, the uptake of mammography in Nigeria has been low. This study evaluated mammography studies in a Nigerian tertiary hospital to use insights from this study to proffer feasible solutions that can improve mammography services and uptake in Nigeria.Methods: This is an IRB-approved retrospective analysis of all mammography studies done at a Nigerian tertiary hospital between March 2022 and February 2023. Anonymized patient data from the routinely filled risk-assessment questionnaires during mammography procedures and the mammography findings were entered into an Excel sheet. Data were analyzed using SPSS version 22, and a significant p was set at < 0.05. Results: A total of 324 women with an average age of 51.06 ± 9.28 years (range 30 – 86 years) underwent mammography, 185 (57.1%) for screening, and 139 (42.9%) for diagnostic evaluation of breast symptoms. Half (49.7%) of the women had dense breasts (ACR-C and D). Community engagement (52%) and self-referral (20%) were the primary paths to mammography, with 20% of the women paying out of pocket for the procedure. Sixty-six ultrasound-guided core needle biopsies were recommended for further diagnostic workup, but 64 were performed, 4 of which were from screening. The positive predictive values of biopsy-proven breast cancer in BIRADS 4 (4/13) and 5 (51/51) lesions were
30.8% and 100% respectively. Fifty-five cancers (55/324; 17.0%) were diagnosed in all, one with a size of 1.4 cm on screening (1/185; 0.5%) and 54 with an average size of 3.6 ± 1.9 cm (range 2.0 - 5.3) on diagnostic workup (54/139; 38.8%). Age at menopause and personal history of previous breast cancer independently predicted BIRADS 5 lesions on mammography, while age independently predicted malignancy at pathology. Conclusions: Observations from this analysis show more screening than diagnostic uptake; cancer detection rates in the screening and diagnostic population, a foundation for future studies that can inform public health policy in Nigeria; and significant risk factors that predict malignant lesions to guide recommendations for risk-based systematic screening in Nigeria, where population screening does not seem feasible.