Drug-Induced Restoration of Cutaneous Delayed Hypersensitivity in Anergic Patients with Cancer

NEOPLASTIC disease in man is often accompanied by defective cellular immunity as manifested by tests for cutaneous delayed hypersensitivity1 or by more sophisticated methods related to the ability of lymphocytes to react with target or tumor cells.2 Although it is unclear whether diminished immunocompetence precedes or is a result of advancing cancer, the high prevalence of neoplasia in congenital immune deficiency states, and in immunosuppressed transplant recipients,3 suggests that attenuated immunity contributes to the progression of malignant tumors. Patients with such tumors who remain responsive to delayed hypersensitivity testing have a more favorable prognosis than those who lack cellular immunity. . . .