Excess IgD bearing lymphocytes in patients with malignant melanoma.

B lymphocytes from the peripheral blood of 15 melanoma patients and 14 normal adults were studied using immunofluorescence to IgA, IgG, IgD and IgM surface markers. The total number of peripheral blood B lymphocytes was increased in the melanoma patients (1048/mm(3)) compared with normal controls (504) (P<0·01).The expression of excess IgD bearing lymphocytes in these melanoma patients may reflect a derepression of oncofoetal type.