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Updated: Jun 19, 2026

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
A case of melanoma in xeroderma pigmentosum
T Narayana Rao1, A Bhagyalaxmi, Kamal Ahmed
1Department of Dermatology, Andhra Medical College, Visakhapatnam, Andhra Pradesh, India.
Abstract:
Xeroderma pigmentosum (XP) was first described in 1874 by Hebra and Kaposi. [1] It is a rare autosomal recessive disorder characterized by photosensitivity, pigmentary changes, premature skin aging, and malignant tumor development due to cellular hypersensitivity to ultraviolet radiation resulting from a defect in DNA repair. The basic defect in XP is in nucleotide excision repair (NER), leading to deficient repair of damaged DNA. A 12-year-old boy presented with a large growth over the right side of the forehead. The lesion was first noticed before two years as a 2 x 2 cm 2 mass. It was slowly growing and attained the present size of 10 x 8 x 7 cm 3 . The surface showed ulceration with areas of hemorrhage and blackish pigmentation. Also, the patient had hyperpigmented macules over the skin since early childhood. The macules appeared initially over the face and later developed over the other areas of the body. The macules were more over the sun exposed areas. He also had photophobia and both eyes showed corneal opacities. Histopathological examination of the excised growth showed features consistent with melanoma. This case is being presented because of its rare association with xeroderma pigmentosum patients in India.
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