Influence of aging and chemoradiotherapy on leucocyte function in oral cancer patients

Leucocyte functions and the influence of chemoradiotherapy were examined in three age groups of patients with oral cancer. The groups consisted of 66 patients below 65 years old (group A): 40 patients between 65 and 80 years old (group B); 20 patients over 80 years old (group C). 20 healthy individuals (45.8 +/- 9.6 years old) were chosen as controls. Originally, no significant differences in leucocyte count, CD3 population, CD4/CD8 ratio, natural killer activity or phagocytosis of polymorphonuclear leucocytes (PMNL) were found in the patients. However, T cell blastogenesis, lymphokine-activated killer cell activity and superoxide production of PMNL were all suppressed. These functions were further suppressed by cancer therapy, the greatest suppression being seen in group C. Compared to controls and group A, the generation of interleukin-1, interleukin-6, tumour necrosis factor-alpha and granulocyte-macrophage colony-stimulating factor were markedly suppressed in group C. These results show that very old cancer patients are already in an immunologically suppressed condition and that the leucocyte functions of these patients are further impaired by cancer therapy.