The in vitro effect of a calf thymus extract on the peripheral blood lymphocytes of sixty-six melanoma patients.

The in vitro effect of a calf thymus extract (TP-1) on peripheral blood lymphocytes was evaluated in sixty-six melanoma patients. Twenty out of forty-five stage I and seventeen out of twenty-one stage IIb patients presented depressed T lymphocyte values. A statistically significant increase in E-rosette-forming cells (E-RFC) was observed in seventeen (85%) stage I and twelve (70.5%) stage II patients. In thirteen (65%) stage I and eight (47%) stage II patients E-RFC reached normal values. Our results indicate that the fall of T lymphocytes in the peripheral blood of melanoma patients is often related to an increase in TP-1 sensitive cells which suggests the possibility of a thymic hormone deficiency in these patients.