Adoptive immunotherapy for gastric cancer using zoledronate-activated killer cells: A prospective observational study

For several years, adoptive immunotherapy (AIT) has been performed using autologous zoledronate-activated killer (ZAK) cells to develop a novel modality for cancer treatment. In the current study, data from 50 patients with incurable gastric cancer were analyzed. Patients were treated with AIT using intravenous ZAK cells every 3-4 weeks in combination with chemotherapy of the physician's choice. The possible clinical benefits were subsequently examined. The median overall survival (OS) time of all patients was 7.5 months. In patients that received 5 or more rounds of treatment, the OS was 13.5 months. Additionally, the OS times of 1st, 2nd or later line chemotherapy with ZAK cell AIT were 27.3 months and 13.3 months, respectively. No objective response was observed and the disease control rate was 67.9%. No severe adverse event was recorded. Functional Assessment of Cancer Therapy-Biologic Response Modifier analysis revealed possible improvement of quality of life after ZAK cell AIT. Univariate analysis revealed a significant positive association between longer survival times and baseline lymphocyte percentages in white blood cell counts (P<0.001), serum albumin (P=0.001), C-reactive protein (P=0.006), carbohydrate antigen (CA)19-9 (P=0.010), neutrophil-lymphocyte ratio (P<0.001) and Glasgow prognostic score (GPS). Only the GPS value (P=0.024) was a significant survival marker when analyzed using the multivariate Cox proportional hazards model. Although the results cannot provide a definitive conclusion, the current suggested that ZAK cell AIT in combination with chemotherapy is safe, feasible and may be a promising treatment option for patients with incurable gastric cancer. The GPS value at baseline may be a potential biomarker for chemo-immunotherapy.