Studying the urine microbiome in superficial bladder cancer: samples obtained by midstream voiding versus cystoscopy.

Preliminary data suggest that the urinary microbiome may play a role in bladder cancer. Information regarding the most suitable method of collecting urine specimens is needed for the large population studies needed to address this. To compare microbiome metrics resulting from 16S ribosomal RNA gene sequencing between midstream, voided specimens and those obtained at cystoscopy.

Adults, with a history of superficial urothelial cell carcinoma (non-muscle invasive bladder cancer) being followed with periodic surveillance cystoscopy had a urine sample collected by a mid-stream, voided technique and then from the bladder at cystoscopy. Urine samples underwent 16S ribosomal RNA gene sequencing on the Illumina MiSeq platform.

22 subjects (8 female, 14 male) were included. There was no significant difference in beta diversity (diversity between samples) in all samples between collection methods. However, analysis by sex revealed a difference between voided and cystoscopy samples from the same individual in males (p = 0.006, Adonis test) but not in females (p = 0.317, Adonis test). No differences were seen by collection method in any alpha diversity (diversity within a sample) measurement or differential abundance of taxa.

Beta diversity of the urine microbiome did differ by collection method for males only. This suggests that the urinary microbiomes of the two collection methods are not equivalent to each other, at least in males, which is the sex that bladder cancer occurs most frequently in. Therefore, the same collection method within a given study should be used.

BMC urology. 2020 Jan 28*** epublish ***

Suchitra K Hourigan, Wei Zhu, Wendy S W Wong, Nicole C Clemency, Marina Provenzano, Thierry Vilboux, John E Niederhuber, John Deeken, Simon Chung, Kim McDaniel-Wiley, Donald Trump

Inova Children's Hospital, 3300 Gallows Road, Falls Church, VA, 22042, USA. ., Inova Translational Medicine Institute, 3300 Gallows Road, Falls Church, VA, 22042, USA., Inova Schar Cancer Institute, 3224 Gallows Road, Fairfax, VA, 22031, USA., Department of Urology, Inova Fairfax Medical Center, 3300 Gallows Road, Falls Church, VA, 22042, USA.