Potential relationship between lung microbiomes and lung cancer patients undergoing resection

Aim: Lung cancer remains a leading cause of global mortality, with its pathophysiological mechanisms still under investigation. This study explores the lung microbiome by analyzing lung tissue and bronchoalveolar lavage (BAL) samples. Our aim is to identify significant differences between the microbiomes of these two sample types and evaluate whether BAL is a reliable representation of the lung microbiome. Material and Method: The study includes 20 patients diagnosed with primary lung carcinoma at Istanbul University-Cerrahpaşa between April and October 2024. Participants were individuals aged 18 and over who gave consent; those under 18 and those who had received antibiotic treatment in the last month were excluded. Preoperative evaluations were performed with blood tests and imaging methods, bronchoalveolar lavage (BAL) sampling was performed, and samples were taken from resected lung tissue. Samples were stored at -20 °C, nucleic acid isolation was performed, and the 16S rRNA V3-V4 region was amplified by PCR. Results: Among the participants, 70% were male, 30% female, and 60% were 60 years old or younger. Additionally, 80% were smokers and 20% had COPD. According to TNM staging, 75% were in stages I-II, while 25% were in stages III-IV. Histopathological examinations showed adenocarcinoma in 60% and squamous cell carcinoma in 35%. Microbiome analyses indicated that Proteobacteria was dominant, representing 54.2% in BAL and 66.5% in biopsy samples, with significant differences in alpha and beta diversity. Conclusion: The findings may contribute to personalized treatment approaches. Limitations include a small sample size and absence of a control group, potentially affecting the generalizability of results. This research is a significant step in understanding the relationship between lung cancer and the microbiota. Keywords: KHDAK, microbiome, s16 rRNA sequencing