Recall antigen delayed-type hypersensitivity skin testing in melanoma and acute leukemia patients and their associates.

mune response. It has been demonstrated to correlate with stage of disease (1, 6, 16, 31) and prognosis (2, 3, 14, 20) in many types of cancer. By various mechanisms, including surgery (17, 18), radiotherapy (8, 23), chemotherapy (23), and immunotherapy (11, 15, 32, 33), the human immune response can be altered.These changes can be docu mented with DTH skin tests, and thus this test of immuno logical competence has become an important tool in the management of cancer patients and the evaluation of treat ment (12). DTH skin test responses reflect a complex series of vascular, cellular, and mediator-associated effects (4). Age (9, 29), genetics (7), and environment (previous expo sure to the antigen) are known to have a significant effect on immune response. These factors are rarely considered in selecting appropriate control groups in immunological studies of cancer patients on, for that matter, patients with other diseases. They are of increasing importance when dealing with recall antigens as used in this study and many others. An opportunity to study the possible effects of some of these factors on DTH skin test reactivity occurred during a trial of TF in the treatment of melanoma and acute leuke mia. In this trial, potential TF donors (relatives and friends of the patients) were screened for their appropriateness as donors by a battery of 4 DTH skin tests. The 0TH skin test reactivity for a large (336) group of normal persons, matched to the patients by varying degrees for age, environ ment, and genetic closeness, was available for comparison to the skin test reactivity of the patients themselves. The effect of diagnosis and stage of disease on the DTH skin test response of the patients was also investigated.