The prevalence of incidental breast malignancy in women below 35 years old with firoadenoma at university teaching hospital, Lusaka, Zambia

Abstract

The most common cause of a discrete breast mass is fibroadenoma. Malignancy within a fibroadenoma is very rare with a reported incidence of 0.1 to 0.3%. Despite an audit report from the University Teaching Hospital histology lab done from January to December in 2013 showing that 11% of clinically diagnosed fibroadenoma were found to be malignant on histology, the prevalence of incidental cancer within a fibroadenoma is not known. This study focuses on the prevalence of incidental malignancy in patients with fibroadenoma. The findings will provide evidence based recommendations on the management of patients less than 35 years old with fibroadenoma at UTH. The aim of this study was to determine the prevalence of malignancy in fibroadenoma in females less than 35 years old presenting at the University Teaching Hospital during the study period. This was a cross-sectional study involving women less than 35 years of age old, presenting at University Teaching Hospital with a fibroadenoma. The target population was women with clinically and histologically confirmed fibroadenoma. The inclusion criteria was all women less than 35 years of age who presented with breast lumps that were either clinically or histologically confirmed as fibroadenoma. The breast lumps were excised under local anesthesia and the specimen analyzed for the presence of malignancy after confirming it being a fibroadenoma. The sample size was 116 using the prevalence formula. The mean age was 22.8 years old and the mean size of fibroadenomas was 3.35 cm. None of the cases presented with breast cancer arising from within the fibroadenoma. The study has demonstrated for the first time in Zambia that the prevalence of the incidental breast malignancy in fibroadenoma was extremely rare in women less than 35 years. Therefore, management of histologically confirmed fibroadenoma in women less than 35 years can be safely managed conservatively. KEY WORDS: Incidental malignancy, Fibroadenoma, 35 years, Conservative management