Mucocutaneous paraneoplastic changes may be an important clue to the presence of an otherwise asymptomatic malignancy. Indeed, in over one third of patients, complaints related to the paraneoplastic condition precede the diagnosis of the malignancy by months or years. Cutaneous paraneoplastic syndromes may also be suggestive of the specific type of cancer present. Even though many of the dermatoses linked to cancer can also be found in benign disorders or represent idiopathic illness, it behooves the physician to do a thorough workup to rule out a new or recurrent tumor in a patient with such lesions. The manner in which tumors mediate the development of noncontiguous dermatoses has not been established. An attractive concept is that a cytokine secreted either by the tumor or by accessory cells in response to the tumor is responsible. In regard to treatment, improvement in the skin lesions generally requires eradication of the cancer. Finally, the presence of a cutaneous paraneoplastic syndrome often carries grave oncologic implications. The majority of patients with these syndromes succumb to the tumor.