ABSTRACT
Human skin provides mechanical protection to the host against various physical,
biological, and chemical environmental agents (1). The skin in the process is
itself a potential target of environmental toxins and carcinogens. However,
being at the primary interface between the environment and the body, it carries
several inherent defense mechanisms. The eventual failure of the defense mech-
anisms, manifested by deficient repair of DNA damage, fixation of mutations in
critical genes, immune suppression, and a host of other events, may ultimately
lead to carcinogenesis (2). Different cells in skin upon transformation result in
cancers of various types. Most common forms of skin cancers are basal cell carci-
noma, squamous cell carcinoma, and melanoma. Basal cell carcinoma originates
in basal cells and squamous cell carcinoma in keratinocytes within epidermis.
Melanoma results from the transformation of the pigment producing melanocytes
that are distributed in the dermal layer (3).
