Adnexal tumors of the skin in Black Africans: A 21-year comparative morphological analysis

Abstract

Background: There is limited documented literature on the occurrence of tumors of the skin adnexae in the Black African population, and the seeming rarity of these tumors as earlier reported is not unrelated to misdiagnosis with other epidermal tumors, due to their complex, overlapping, and confusing morphological features, and lack of expertise in their diagnosis. Material and Method: A morphological analysis of all diagnosed cases of adnexal tumors of the skin in a Pathology laboratory over a 21-year period (1999-2019) using formalin-fixed paraffin-processed hematoxylin and eosin stained slides and tissue blocks subjected to special stains and immunohistochemical analysis. Results: One hundred and sixty-two adnexal tumors of the skin were diagnosed over the 21-year period. 115 were benign and 47 malignant with an overall male to female distribution of 67: 95. The mean age overall was 40.5 years, while the mean ages for benign and malignant lesions were 35.7 years and 50.9 years, respectively. The most common benign tumors were of eccrine and apocrine differentiation, while sebaceous carcinoma was the most common malignant tumor overall with a male predominance and closely followed by porocarcinoma with a female predisposition. Three (3) patients had recurrent tumors and the diagnosis of 17 cases with generic diagnoses of benign adnexal tumor and malignant adnexal tumors were reviewed based on the 2006 WHO classification of skin tumors. Conclusion: There is an increase in the frequency of tumors of the skin adnexae in our setting due to improved diagnostic capabilities and better health-seeking awareness among patients. These tumors have different biologic potential in terms of aggressiveness and thus require definite diagnosis for further patient management.