Clinical Evaluation of Urinary VOCs as Non-Invasive Biomarkers in Prostate Cancer

Prostate cancer is one of the most common malignancies in men, and current diagnostic tools, such as prostate-specific antigen (PSA) and biopsy remain limited by low specificity and invasiveness. Urinary volatile organic compounds (VOCs) are increasingly recognized as promising non-invasive biomarkers reflecting tumor-associated metabolic changes. This study aimed to evaluate the diagnostic potential of urinary VOCs using a semiconductor-based gas-sensor platform.

Urine samples from patients with prostate cancer and non-cancer controls were analyzed using an array of five metal oxide semiconductor sensors (S1-S5), each tuned to specific VOC groups. Measurements were performed under six thermal cycles with sequential heater voltages (2000-5000 mV). Sensor signals were converted into characteristic parameters following a validated extraction protocol. Logistic regression was used to determine discriminatory performance.

Ten candidate VOC parameters were initially identified with significant intergroup separation. In the multivariate model, the resistance gap at 2500 mV targeting trimethylamine and methyl mercaptan remained independently associated with prostate cancer. When combined with PSA in the logistic regression model, this VOC-derived signal yielded an AUC of 0.88, with a 77% sensitivity and 88% specificity for distinguishing cancer from controls.

Urinary VOCs demonstrate strong potential as non-invasive biomarkers for prostate cancer detection. The diagnostic performance of the combined VOC-PSA model (AUC 0.88) exceeded that of PSA alone, underscoring the feasibility of gas-sensor platforms in urologic cancer diagnostics and supporting validation in larger, prospective cohorts.