Bacteria-related spontaneous and therapeutic remission of human malignancies

The development of specific immunotherapeutic approaches to cancer treatment is making progress. However, a crucial clinical break-through in cancer vaccination is still missing. Spontaneous clinical remissions of malignancies are a rare phenomenon. The mechanisms are not clear but there are remissions described in correlation with bacterial infections. The use of bacteria or bacterial components might be a promising path for non-specific immunotherapy of tumors and might be a helpful adjuvant for specific immunotherapy. Here, we briefly review spontaneous remissions of various malignancies in humans, the impact of bacterial infection on tumor regression and the utilization of bacterial components in clinical trials.