Cutaneous metastases from genitourinary malignancies.

OBJECTIVES: To review the world literature for reports of cutaneous metastases from primary genitourinary malignancies and compare them with our experience during a 10-year period. Cutaneous metastases from primary visceral malignancies are uncommon manifestations of advanced disease. Among patients with urologic malignancies, the incidence and appearance of cutaneous metastases are not well established and recognition is poor among practicing urologists.
METHODS: A Medline search and manual bibliographic review was performed to identify peer-reviewed reports pertaining to cutaneous metastases from all visceral malignancies. A comparative review of all pertinent cases arising from primary urologic malignancies was performed. A comprehensive search of our institution's tumor registry was performed to identify all analytic cases of urologic malignancy diagnosed, treated, and followed up between 1990 and 2000. Clinical and pathologic data were collated.
RESULTS: We identified 2,369 reported cases of cutaneous metastases arising from 81,618 primary solid visceral malignancies, for an overall incidence of 2.9%. Dermatologic spread from primary urologic malignancies of the kidney, bladder, prostate, or testes was noted in 116 (1.3%) of 10,417. The incidence of cutaneous metastases from the kidney, bladder, prostate, and testes was 3.4%, 0.84%, 0.36%, and 0.4%, respectively. Overall, 436 cases of cutaneous metastases from urologic organs were identified in the English-language literature. We identified nine additional cases of pathologically confirmed cutaneous metastatic urologic tumors at our institution in the past 10 years. The most common presentation was an infiltrated plaque or nodules. Most cases displayed clinical features that mimicked common skin disorders. The median disease-specific survival was less than 6 months from the presentation of cutaneous metastasis.
CONCLUSIONS: Cutaneous metastases from urologic tumors are uncommon and occur in 1% of patients with advanced disease. Urologic skin metastases are most common from renal tumors, followed by those of the bladder and then prostate. Their clinical appearance may mimic other common dermatologic disorders affecting patients with advanced malignancies. Definitive diagnosis requires an index of suspicion and skin biopsy. Cutaneous metastases from urologic malignancies are associated with a poor prognosis.