Changes in tumor immunity during therapy determined by leukocyte adherence inhibition and dermal testing.

Leukocyte adherence inhibition (LAI) is an easily carried out in vitro test for tumor reactivity which is based on the prevention of adherence of leukocytes incubated with antigen to which the donor is immune. In this study a comparison is made with dermal response to tumor antigen. A total of 234 patients were tested, 74 of whom had melanoma, 111 of whom had squamous cell carcinoma of the head and neck, 18 of whom had neuroblastoma and 31 of whom had other tumors. Forty-two persons without tumors acted as controls for the LAI test. A high degree of correlation was found between LAI and dermal response. Furthermore, LAI exhibited marked tumor specificity and showed a ten-fold greater sensitivity than dermal response. LAI may be used to monitor serial changes in tumor reactivity in cancer patients.