A Pilot Study Of Optical Spectral Techniques To Identify Breast Tumor And Hepatocellular Carcinoma

PartⅠEstimate the optical properties of human breast tissues using a single integrating sphere systemObjective The optical properties of tissues determine the distribution of light within the tissue. Measurement of optical properties of tissues is the foundation of the spectral diagnosis. The purpose of this study is to measure the optical properties of various types of breast diseases to find out the differences in order to explore spectroscopy diagnosis of breast diseases.Methods The tissues specimens detected were divided into 4 groups:28 cases of normal breast tissues,22 cases of breast cancer,8 cases of fibroadenoma,13 cases of mastopathy. All the specimens were obtained from patients with the modified radical mastectomy or partial breast resection and identified by pathological diagnosis. The optical parameters were measured in 10 nm steps using single-integrating-sphere system in the wavelength range of 400 nm to 2200 nm.Results In the wavelength range, The optical parameters and their differences between the breast tissues varied according to the different wavelengths. The absorption coefficient of each group was statistically significantly different (P<0.05) (480 nm,1450 nm,1640 nm, 1720 nm,1840 nm and 1930 nm). The absorption coefficient of normal breast tissue and breast cancer significantly different (480 nm,1450 nm,1640 run,1720 nm,1840 nm and 1930 nm); that of normal breast tissue and fibroadenoma was significantly different (400 nm,480 nm,1450 nm,1640 nm,1720 nm and 1840 nm); that of normal breast tissue and mastopathy was significantly different (480 nm,1450 nm,1640 nm,1720 nm and 1840 nm); that of breast cancer and fibroadenoma was significantly different (1450 nm,1640 nm and 1840 nm). that of fibroadenoma and mastopathy was significantly different (1450 nm,1640 nm and 1840 nm) (P<0.05). Scattering coefficient of each group was significant different at wavelength of 400 nm and 480 nm (P<0.05). Compared with normal breast tissue, the scattering coefficient of breast cancer, fibroadenoma and mastopathy was significantly different (P<0.05). Linear discriminant analysis (LDA) showed that the discriminat accuracy of normal breast tissue was 82.1%, the discriminant accuracy of breast cancer was 54.5%, the discriminant accuracy of fibroadenoma was 100%, the discriminant accuracy of mastopaty was 30.8%. For all tested samples the correct classification rate was 66.2%.Conclusion The results help to understand the optical properties of human breast tissue. Different pathological types of breast tissues have optical characteristics, with which spectroscopic methods to diagnose breast disease may be developed. Part II Different optical properties between human hepatocellular carcinoma tissues and nontumorous hepatic tissues in vitroObjective The optical properties of tissues determine the distribution of light within the tissue. This information is most valuable for the optical techniques of diagnostic and therapeutic applications. The purpose of this study was to measure the optical properties of hepatocellular carcinoma (HCC) tissues and nontumorous hepatic tissues and compare the difference between them.Methods A total of 55 tissue samples (HCC tissue, n=38; nontumorous hepatic tissue, n=17) were obtained from patients with HCC resection. The optical parameters were measured in 10 nm steps using single-integrating-sphere system in the wavelength range of 400 nm to 1800 nm.Results It was found that the optical properties and their differences varied with the wavelength for the HCC tissue and the nontumorous hepatic tissue in the entire wavelength range of research. The absorption coefficient of the HCC tissue (1.48±0.99 mm-1,1.46±0.88 mm-1,0.86±0.61 mm-1,2.15±0.53 mm-1,0.54±0.10 mm-1,0.79±0.15 mm-1) was significantly lower than that of the nontumorous hepatic tissue (2.79±1.73 mm-1,3.13±1.47 mm-1,3.06±2.79 mm-1,2.57±0.55 mm-1,0.62±0.10 mm-1,0.93±0.16 mm-1) at wavelengths of 400 nm,410 nm,450 nm,1450 nm,1660 nm and 1800 nm, respectively (P<0.05). The reduced scattering coefficient of HCC tissue (5.28±1.70 mm-1,4.91±1.54 mm-1,1.26±0.35 mm-1) and nontumorous hepatic tissue (8.14v3.70 mm-1,9.27±3.08 mm-1,2.55±0.57 mm-1) was significantly different at 460 nm,500 nm and 1800 nm respectively (P<0.05). Linear discriminant analysis (LDA) showed that non-tumor tissue identification accuracy rate was 94.1%; liver tissue discrimination accuracy rate was 100%. For all tumor tissue and non-tumor tissue samples,the correct classification rate was 98.2%. Conclusion These results provide a better understanding of optical properties in human liver tissues. Different pathologic liver tissues have different optical properties, and all these differences would be helpful in the diagnosis of HCC and clinical applications of optical techniques.