[Solitary metastasis of a clear cell renal cell carcinoma after a 20 year latency clinically simulating a vascular tumor].

History And Clinical Findings: A 72-year-old woman was referred because of progressive skin discoloration with venectasia and swelling in the left lower leg, the possible diagnosis being atypical varicose veins. 20 years before she had a right nephrectomy for "clear-cell" renal adenocarcinoma with subsequent tele-cobalt radiotherapy. On examination a pulsating swelling was palpated over the hyperpigmented area of the skin with venectasia.

Investigations: She had hypercholesterolaemia (254 mg/dl) and hyperuricaemia (uric acid 6.2 mg/dl). Duplex sonography, angiography and computed tomography of the lower leg revealed a vascular tumour with infiltration of the right head of the gastrocnemius.

Diagnosis, Treatment And Course: Because an arteriovenous fistula within a vascular soft-tissue tumour of unknown histology was suspected, a wide resection was performed. Histopathological examination revealed a metastasis of a clear-cell adenocarcinoma. Postoperative diagnostic tests discovered no other findings suspicious of malignancy. It is therefore to be assumed that the resected tumour was a solitary metastasis of the renal adenocarcinoma removed 20 years previously.

Conclusion: Even rare causes should be considered in the differential diagnosis of vascular tumour, as this case of a solitary metastasis after a latency of 20 years demonstrates.