Early efficacy of stereotactic body radiation therapy combined with adoptive immunotherapy for advanced malignancies

Stereotactic body radiation therapy (SBRT) concentrates radiation to a predefined target, affecting all the cells within it. Adoptive immunotherapy is not restricted by the major histocompatibility complex (MHC) in recognizing and eliminating target cells. We investigated the effects of the combined modality of SBRT and adoptive immunotherapy on patients with advanced malignant tumors. The database of 316 patients with 845 tumors who underwent SBRT between April, 2010 and February, 2012 was retrospectively reviewed. Of the 316 patients, 145 received biological immunotherapy and were assigned into the observation group, whereas the remaining patients constituted the control group. Patients in the two groups were recorded on efficacy assessment, Karnofsky performance status (KPS), cell phenotype expression level in vitro and the percentages of lymphocyte subsets and ratio of CD4⁺/CD8⁺ lymphocytes in the peripheral blood. Following treatment, the total effectiveness [complete response (CR) + partial response (PR)], the KPS score, the percentages of lymphocyte subsets and the CD4⁺/CD8⁺ lymphocyte ratio in the observation group were higher compared to those in the control group, with a statistically significant difference (P<0.05). The expression of CD3⁺ and CD3⁺CD56⁺ cytokine-induced killer (CIK) cells were increased from 56.76±4.54% and 11.32±2.96% to 94.67±4.46% and 32.65±1.12%, respectively, when cultured in vitro (P<0.01). The percentages of lymphocyte subsets and the CD4⁺/CD8⁺ lymphocyte ratio were significantly increased compared to prior to treatment in the observation group (P<0.05). SBRT combined with adoptive immunotherapy may be a novel therapeutic option for patients with advanced malignant tumors.