Histopathologic profile of cutaneous cystic lesions in teaching hospital, Nnewi, South-east, Nigeria

Abstract

Background A cyst is an enclosed space or abnormal sac within a tissue, usually containing fluid or semisolid matter and lined by epithelium. Aims and objectives To study all the cutaneous cystic lesions with respect to age, sex, anatomic site, and histologic types in a population of Nnewi, South-East Nigerian. It also aimed at highlighting the importance of histology in evaluating and preventing misdiagnoses encountered in cutaneous cystic lesions. Patients and methods A retrospective review was performed on the histopathology register on all histologically diagnosed cutaneous cysts at the Histopathology Department of Nnamdi Azikiwe University Teaching Hospital (NAUTH), Nnewi, Nigeria from 2011 to 2019. Results A total of 94 cutaneous cystic lesions, accounting for 1.3% (94/7204) of all surgical biopsy specimens, were included in this study. An overall clinicopathological correlation showed 26.6% (25/94) accuracy, but 73.4% were incorrectly diagnosed, with 7.4% (5/69) of cases misdiagnosed clinically as malignant lesions and one case of malignant cystic lesion diagnosed clinically as benign cyst. There were 49 males and 45 females, giving a slight male predominance, with male to female ratio of 1.1 : 1. The age ranged from 6 weeks to 79 years, with a mean±SD age of 26.5±21.1 years, and a peak age group of 0–10 years, representing 29.8% (28/94). Benign cutaneous cystic lesions were far commoner than malignant ones and included majorly epidermal inclusion cyst [37.2% (35/94)], pilar cyst [17.0% (16/94)], thyroglossal cyst [12.8% (12/94)], and dermoid cyst [8.5% (8/94)]. The only malignant cutaneous cyst was immature cystic teratoma [1.06% (1/94)]. The anatomic site most frequently affected was the head and neck [63.8% (60/94)]. Conclusion Histopathologic evaluation is still the gold standard in eliminating misdiagnosis of these lesions. Epidermal inclusion cysts followed by pilar cysts were commonest cutaneous cystic lesions in our environment and occur more at the third decade and above, whereas cystic hygroma, dermoid cysts, and brachial cyst were predominant at the first decade of life.