Usefulness of Fluorescent Urine Cytology in the Diagnosis of Urothelial Carcinoma

Abstract

Five-aminolevulinic acid, an amino acid that is metabolized in the cytoplasm to become protoporphyrin IX, is used in photodynamic diagnosis in various carcinomas because it accumulates in higher concentrations in tumor tissue than in normal tissue. 5-Aminolevulinic acid-induced fluorescent urine cytology is more sensitive than conventional urine cytology only in low grade urothelial carcinoma (UC), but it showed a tendency for higher sensitivity in high grade UC. To increase the number of patients and reconsider our previous findings, we compared the sensitivity and specificity of preoperative urine cytology and fluorescent urine cytology in 343 patients diagnosed as having UCs pathologically (215 bladder cancers, 128 upper tract UCs) and 197 non-cancer patients at Osaka Rosai Hospital from March 2013 to December 2019. The sensitivities of fluorescent urine cytology and conventional urine cytology were 81.1% and 63.3% (p<0.001), respectively, and specificities were 92.9% and 93.9% (p=0.84), respectively. The sensitivity of fluorescent urine cytology was superior to that of conventional urine cytology in both low grade UC (76.8% vs 41.1%, p<0.001) and high grade UC (83.1% vs 74.0%, p=0.023).