Urinary excretion of 5-S-cysteinyldopa in patients with primary melanoma or melanoma metastasis.

Urinary excretion of 5-S-cysteinyldopa was studied in 9 patients with primary melanoma. All had 5-S-cysteinyldopa excretion in the normal range. In 8 of the patients excretion values decreased after removal of the tumour. Twenty-four patients with clinical signs of melanoma metastasis were examined for 5-S-cysteinyldopa and dopa+dopamine in the urine. 16 of the 24 had pathologically increased excretion of 5-S-cysteinyldopa and 7 of the 24 had pathological excretion of dopa+dopamine. Six of the latter belonged to the group with increased 5-S-cysteinyldopa excretion and one patient had a borderline value of 5-S-cysteinyldopa. Determination of 5-S-cysteinyldopa seems to be of value in the follow-up of patients operated on for primary melanoma.