[Serum interferon level and (2'-5')-oligo(A) synthetase activity in malignant melanoma].

Both the serum levels of interferon and the activity of lymphocytic (2'-5')-oligoadenylate synthetase (OAS) of 37 patients suffering from malignant melanoma-15 with low (I,I-II,II) and 22 with higher (III,IV,V) Clark levels-were compared with those of a group of healthy controls in order to detect a possible involvement of the interferon system in the pathological process. Previous results obtained in studies on relatively small groups of patients had suggested that melanoma patients with low Clark levels (i.e. biologically early melanoma) show elevated activities of OAS, while those with higher levels show normal values. In our present investigation on a larger sample of patients, we did not find any differences between these two melanoma groups and healthy persons with regard to the OAS activity. Thus we were not able to confirm the provisional results set up by previous studies.