Urinary tyrosine detection for cancer screening and metabolic disorder diagnosis: a comprehensive evaluation of a colorimetric method

Abstract

Abnormal tyrosine metabolism has been observed in various malignancies and metabolic disorders. Urinary tyrosine detection represents a potential non-invasive approach for disease screening. This study aims to evaluate the clinical performance, analytical validity, and practical applications of a colorimetric urinary tyrosine detection method based on modified Millon's reagent for cancer screening and metabolic disorder diagnosis. A comprehensive analysis of clinical trial data involving 8,078 participants was conducted, including 4,375 cancer patients and 3,703 non-cancer controls. The colorimetric test was evaluated for sensitivity, specificity, and compared with high-performance liquid chromatography (HPLC) and spectrophotometry methods. Interference factors including dietary components and medications were systematically assessed. The colorimetric method demonstrated sensitivity of 96.69% and specificity of 99.40% for malignant tumor detection. Positive detection rates varied significantly across disease categories: malignant tumors (96.69%), pigmentary disorders (22.06%), diabetes (21.51%), and healthy individuals (0.60%). Comparison with HPLC showed maximum deviation of 11.4% in low-concentration ranges, with 0% deviation in high-concentration ranges (>500 mg/L). Dietary interference, particularly from seafood (23.3%), meats (20.0%), and alcohol/caffeine (16.7%), resolved completely within 48 hours of abstinence. The evaluated urinary tyrosine detection method shows high sensitivity and specificity for malignant tumor detection in this study population. The semi-quantitative colorimetric approach presents both advantages and limitations that warrant consideration for clinical implementation. Positive results require confirmatory diagnostic procedures.