[Veillonella atypica in tumor as a tripartite interaction: commensal - tumor - patient].

UNLABELLED: Veillonella spp is part of the normal flora of the mouth, bowels and vagina, but in most of the studies the immunomodulatory properties of intestinal microbiota was described. Despite of numerous studies on immunomodulatory activity of the microbiome's, most of them are focused on the intestinal microbiome. On the contrary, last finding of lung cancer patients shows higher level of Capnocytophaga and Veillonella, which may serve as potential biomarkers. Unfortunately, in local tumor microenvironment the competition for access to oxygen and nutrients within the microbiological context are not strictly described. In the case report such unique interaction with importance in clinical course of non small cell lung cancer (NSCLC) was described.

A CASE REPORT: Patient with NSCLC was admitted to surgical procedure. Unluckily, patients before therapy suffered brain trauma (metastases and meningitis were excluded). The oncologic intervention delayed: patients has not receive neoadjuvant chemotherapy. Within near 2 months the infectious process dominated with high acute phase reaction. It predominated over the process of cancer with significant decrease of initial tumor size. After surgical procedure histological examination showed 60% of the tumor was necrotic. Microbiological analysis of tumor specimen reveal Veillonella spp., identified as Veillonella atypica with high abundance. Because the serious complication patients do not receive adjuvant chemotherapy: the surgical resection was complicated by severe systemic inflammatory response syndrome (SIRS) but with low level lactate.

CONCLUSIONS: Our observation indicate significant role of commensal anaerobic bacteria in clinical history of cancer patient, opportunistic type of infectious process as well as therapeuthic prospect: proliferative potential and anaerobic glycolysis of commensal Veillonella reduce access of cancer cells to nutrition's. It shed light on crucial role of innate immune response, acute phase reaction and neutrophils in immunotherapy outcome. Contrary to previous studies with statistical coexistence of several bacteria and cancer our observation was evidence-based: tumor specimen was microbiologically analysed.