Clinical evaluation of a method of quantitative determination of homovanillic acid for the estimation of degree of tumor dissemination process in melanoma of the skin.

Homovanillic acid (HVA) was determined both in 45 patients with different forms of melanoma and those hospitalized on the suspicion of melanoma and in 15 healthy persons. Excretion rate of homovanillic acid within the normal limits was observed in patients with benign melanotic neoplasms of the skin (4.4 +/- 0.56 mg/24 hr) and in local forms of melanotic melanoma of the skin (4.5 +/- 0.24 mg/24 hr). In patients with metastases to regional nodes as well as in patients with locally disseminated forms of melanotic melanoma of the skin the concentration of homovanillic acid increased up to 11.1 +/- 0.93 mg/24 hr. Especially strong concentration of homovanillic acid was registered in patients with disseminated malanotic melanoma of the skin, and it made up 15.7 +/- 2.04 mg/24 hr. There was evident tendency to the elevation of HVA excretion level as generalization of the process which was taking place. The data obtained enable the authors to recommend the determination of HVA excretion as an additional diagnostic test as well for prognosis of melanoma development together with other clinicomorphological data.