Defective monocyte chemotactic responsiveness in patients with multiple myeloma and benign monoclonal gammapathy.

The chemotactic responsiveness of peripheral blood monocytes was evaluated in three groups of subjects: 32 patients with multiple myeloma, 27 subjects with benign monoclonal gammapathy, and 64 normal controls. Monocyte chemotactic responsiveness was significantly depressed both in multiple myeloma patients (P<0.001) and in subjects with benign monoclonal gammapathy (P<0.001) as compared to that found in the control population. Although the results of chemotactic response obtained in multiple myeloma and in benign monoclonal gammapathy patients were largely overlapping, a significant difference was also found between the mean values of the two groups (P<0.025). The results support the hypothesis that myelomatosis, similarly to other neoplasms, may affect monocyte migratory activity thus hindering immunologically mediated destruction of tumour cells. [ABSTRACT FROM AUTHOR]