Cutaneous metastases in renal cell carcinoma.

Cutaneous metastasis from renal cell carcinoma is believed to be rare. We present our experience with 10 (3.3%) cases seen in the last 12 years among 306 cases of renal adenocarcinoma treated at our center. There were 9 males and 1 female. Age ranged from 30 to 65 years (average 45 years). 5 patients had skin metastases at the time of presentation (stage IV). In one of them the skin nodule, rather than urologic symptoms, was the presenting complaint. 5 patients presented with skin metastasis during follow-up after nephrectomy. The average time to skin metastasis was 51 months for patients in stage I and 13 months in stage IIIb. The scalp was the most common site of metastasis followed by chest and abdomen. 90% of patients had secondaries in at least one other site, most commonly in lungs (4 cases) and bones (5 cases). 4 patients were treated with interferon-alpha 6 MIU, subcutaneously, three times a week for varying periods from 3 to 4 months but there was no response. In conclusion, cutaneous secondaries from RCC, though uncommon, are not very rare. A few patients may present with a skin mass before detection of the renal tumor. Patients with low-stage disease at presentation may also develop cutaneous secondaries, therefore a prolonged follow-up is required. The commonest site for cutaneous metastasis from RCC is the scalp and face. Most patients had at least one other site of systemic metastasis, hence they were not candidates for curative therapy. Interferon therapy was not helpful. Mean survival after detection of cutaneous metastasis was 7 months. Copyright 2000 S. Karger AG, Basel.