medwireNews: Individuals with urothelial bladder cancer (UBC) have a distinct urinary volatile organic compound (VOC) profile that could potentially be used as a biomarker for diagnosis and surveillance, UK research suggests.
For the study, urine samples from 305 individuals (median age 70 years, 66.2% men) undergoing diagnostic cystoscopy or surveillance for UBC were analyzed using gas chromatography–mass spectrometry.
The diagnostic group, who all had hematuria, comprised 21 individuals with a new UBC diagnosis and 125 without cancer, while the surveillance group included 75 participants with recurrent UBC and 84 who were recurrence-free at the time of the study.
Chris Probert (University of Liverpool, UK) and co-investigators report in the British Journal of Cancer that the analysis identified 10 VOCs that significantly differed in abundance between the 96 participants with UBC and the 209 without. Of these VOCs, three were significantly decreased in the UBC group and seven were significantly increased.
In addition, the researchers observed similar results when only the surveillance group was considered, but in this case six VOCs significantly differed (three decreased and three increased) between the individuals with recurrence and those who remained recurrence-free.
By contrast, there were no significant differences in the VOC profiles of people with new versus recurrent UBC cases.
“[S]imilar VOC patterns were observed between these groups, that differed from the controls, suggesting a distinct VOC signature for UBC,” Probert et al remark.
Using this information, the team created two biomarker panels – a diagnostic panel that included eight VOCs for use alongside flexible cystoscopy, and a surveillance panel with six VOCs as a potential way of reducing from annual to biannual endoscopy.
They found that, when applied to the cancer versus control dataset, the diagnostic model had an area under the receiver operating characteristic curve (AUC) of 0.77, a sensitivity of 71%, and a specificity of 72% for the detection of UBC.
The surveillance panel had an AUC of 0.80, a sensitivity of 71%, and a specificity of 80% when applied to the recurrence versus no recurrence dataset.
“Therefore, 20% of negative test results would be a false negative, with a similar proportion of false positives,” the authors note.
They add that although the surveillance model could reduce demand for cystoscopy, it would be “at the expense of delaying the diagnosis of recurrent UBC by up to 12 months in the false negatives and unnecessarily exposing patients to the risks of cystoscopy in the false positives.”
In spite of this, Probert and colleagues conclude that their “results show promise,” and suggest that “[u]rinary VOC analysis may find utility in combination with more established surveillance tests,” rather than being used as a standalone investigation.
medwireNews is an independent medical news service provided by Springer Healthcare Ltd. © 2022 Springer Healthcare Ltd, part of the Springer Nature Group