[IgG levels in the sera of melanoma patients (author's transl)].

397 sera from 185 melanoma patients have been tested. We classified our subjects into three groups, according to the stage of disease. An alteration of the level of IgG 4 sub-class was found and related to the extension of the disease. The percentage of abnormalities was more frequent in stage II and III (55 p. 100 and 53 p. 100) than in stage I (19 p. 100). High titers of IgG 4 subclass were essentially detected in advanced disease. The biological significance is discussed.