Enhancing detection of bladder carcinoma in situ by 3-dimensional optical coherence tomography

Purpose: We examined the usefulness of 3-dimensional optical coherence tomography to enhance the diagnosis of urothelial carcinoma in situ. Materials and Methods: By expressing SV40T antigen with uroplakin II promoter, carcinoma in situ readily develops in SV40T transgenic mice at about ages 8 to 20 weeks and then frank high grade papillary carcinoma develops in bladder epithelium. We examined 10 control and 40 SV40T mice during weeks 8 to 20 after birth by parallel en face white light imaging and 3-dimensional optical coherence tomography, and compared results with histology findings. We applied quantitative analysis of computer aided detection to 3-dimensional tomography images to enhance the diagnosis of carcinoma in situ, including 3-dimensional segmentation, speckle reduction, fast Fourier transform analysis, and standard deviation and histogram evaluation. Results: We identified carcinoma in situ in 23 SV40T mice by histology. Most carcinoma could not be detected by en face imaging and 2-dimensional optical coherence tomography but was well differentiated by 3-dimensional optical coherence tomography. The 56.5% sensitivity and 61.5% specificity of 2-dimensional optical coherence tomography for carcinoma in situ diagnosis were significantly enhanced by 3-dimensional optical coherence tomography to 95.7% and 92.3%, respectively (p ≤0.031). Conclusions: On quantitative analysis of increased urothelial heterogeneity induced by carcinogenesis we noted that 3-dimensional optical coherence tomography enabled accurate differentiation of carcinoma in situ from normal bladder and benign lesions. Results reveal the potential of cystoscopic 3-dimensional optical coherence tomography to significantly enhance the clinical diagnosis of nonmuscle invasive bladder cancer, particularly carcinoma in situ.