HISTOPATHOLOGICAL STUDY OF BENIGN MELANOCYTIC NAEVI

Benign Melonacytic Naevi

Abstract

Objective: To study the histological spectrum and types of benign melanocytic naevi and to observe unusual/atypical histological features in these lesions.
Design: An observational study with prospective data.
Place and Duration of Study: 1st June 1997 to 30th June 1998 at department of Pathology PNS Shifa, Karachi.
Materials and Methods: A total of 50 consecutive cases of melanocytic naevi were studied. Skin biopsies were taken by the Dermatologist from the patients with a primary clinical diagnosis of naevus/mole. Relevant data was recorded.
Results: Majority of cases 24(48%) were in the third decade with female preponderance (56%). Commonest site was the face (66%). Thirty percent cases showed lentiginous proliferation. Acanthosis was observed in 26% cases and effacement in 12%. Twelve percent cases showed mild patchy infiltration by the inflammatory cells. Foreign body reaction along with inflammation was seen in 8% cases. Nuclear pleomorphism with slight variation in size, shape and staining was observed in 8% of the lesions. No architectural disarray or other atypical histological features fulfilling the criteria of dysplastic naevus or malignancy were observed.
Conclusion: Face was the most common site and intradermal naevus was the commonest lesion. Few histological features like lentiginous proliferation, multinucleated naevus cells, foreign body reaction, fatty infiltration, linear fibrosis and acanthosis were observed. However no cytological features for dysplasia or malignancy were present