Giant congenital melanocytic nevus (GCMN) is a very rare condition with an estimated incidence of between 1/20,000 and1/500,000 birth, characterized by a large brown to black skin lesions. It is caused due to genetic mutations which lead to defective proliferation/differentiation/migration of melanoblasts. The risk of transformation of GCMN to malignant melanoma varies between 0 and 3.8%. Besides malignant transformation, patients with GCMN need to be periodically assessed for neurological abnormalities and psychosocial impairment. Here we present a case of 24 years adult who presented with a progressively extensive brownish-black skin lesion of approximately 40 cm over his back. In view of the potential severe complications as well as psychological trauma we draw clinicians’ attention for a timely diagnosis and management.

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Ravinder Singh

Medical Officer, Dermatology DR RKGMC Hamirpur H.P India