An experimental and algorithm-based study of the spectral features of breast cancer patients by a photodiagnosis approach.

In the present study, the spectral diagnosis of blood plasma samples of breast cancer patients and an equal number of normal controls was investigated. A set of ratio parameters was acquired by employing SXS and FES. The samples were also analyzed statistically by employing Welch two-sample t-tests, and the effects of three ratio parameters, R1, R2, and R3, were also studied by plotting them against the subject numbers. A linear discriminant was also applied to verify the exact classification of normal control and breast cancer patients. It was observed that the levels of biofluorophores such as porphyrin, NADH, tryptophan and flavins were elevated 2- to 3-fold for breast cancer patients compared to normal controls, with an accuracy of approximately 100 %. We have also confirmed the validity of the obtained experimental results by using an advanced robust diagnostic algorithm. The experimental results of the current study may have a vital and substantial impact on the detection and screening protocols used for future breast cancer patients. The spectral analysis of body fluid could be of great value to add to and enhance the current procedures with an accuracy of approximately 100 % with limited number of samples. The results and objectives of this preliminary study were encouraging and useful for the discrimination of the features of breast cancer patients compared to those of normal controls.

A study for the detection of kidney cancer using fluorescence emission spectra and synchronous fluorescence excitation spectra of blood and urine.

In this study, we compared different types of biomolecular markers in kidney cancer patients and in normal healthy controls, using fluorescence emission spectra and synchronous fluorescence excitation spectra. We were able to provide an accurate classification of the spectral features of kidney cancer patients relative to that of normal controls, in terms of the concentration ratios of biomolecules (viz., tryptophan, NADH, FAD, basic porphyrin, and acidic porphyrin) based on the intensity of their spectral peaks. The specificity and sensitivity of the method were 90%. The rationale of our current approach is to evolve an innovative protocol for the spectral characterization of in vitro optical analyses suitable for both small clinics and hospitals.

A parallelism between spectral grading and Gleason grading of malignant prostate tissues.

Gleason score is the most common method of grading the virulence of prostate malignancy and is based on the pathological assessment of morphology of cellular matrix. Since this involves the excision of the tissue, we are working on a new, minimally invasive, non-contact, procedure of spectral diagnosis of prostate malignancy. In this preliminary in vitro study reported here, we have analyzed 27 tissue samples (normal control=7: benign=8: malignant=12) by Stokes' shift spectra (SSS) to establish a one-to-one correspondence between spectral grading and Gleason grading.

Optical biopsy of benign and malignant tissue by time resolved spectroscopy.

Pathological condition of malignant tissue could be analyzed by spectral domain or time domain spectroscopy, the two being the complementary to each other in optical biopsy (OB) of cancer. This paper reports results of time resolved emission spectroscopy (TRS) of 24 excised tissue samples of breast and prostate (normal control = 12; benign = 4; malignant = 8), employing a 390 nm, 100 fs, Ti-Sapphire laser pulses.The fluorescence decay times were measured using streak camera and the resultant data were fitted for single and bi-exponential decays with reliability of 97%. Our results show the distinct difference between normal, benign and malignant tissues mostly due to the emission spectra of Nicotinamide Adenine Dinucleotide (NADH), Flavin Mononucleotide (FAD) and also due to the heterogeneity of micro environments associated with the diseased tissues. In this short report, fit is also shown that TRS of breast tissues are similar to those of prostate tissues.

Resonance Raman and Raman spectroscopy for breast cancer detection.

Raman spectroscopy is a sensitive method to detect early changes of molecular _composition and structure that occur in lesions during carcinogenesis. The Raman spectra of normal, benign and cancerous breast tissues were investigated in vitro using a near-infrared (NIR) Raman system of 785 nm excitation and confocal micro resonance Raman system of 532 nm excitation. A total number of 491 Raman spectra were acquired from normal, benign and cancerous breast tissues taken from 15 patients. When the 785 nm excitation was used, the dominant peaks in the spectra were characteristic of the vibrations of proteins and lipids. The differences between the normal and cancerous breast tissues were observed in both the peak positions and the intensity ratios of the characteristic Raman peaks in the spectral region of 700-1800 cm(21). With 532 nm excitation, the resonance Raman (RR) spectra exhibited a robust pattern of peaks within the region of 500-4000 cm(21). The intensities of four distinct peaks at 1156, 1521, 2854 and 3013 cm(21) detected in the spectra collected from normal breast tissue were found to be stronger in comparison with those collected from cancerous breast tissue. The twelve dramatically enhanced characteristic peaks, including the enhanced amide II peak at 1548 cm(21) in the spectra collected from cancerous breast tissue, distinguished the cancerous tissue from the normal tissue. Principal component analysis (PCA) combined with support vector machine (SVM) analysis of the Raman and RR spectral data yielded a high performance in the classification of cancerous and benign lesions from normal breast tissue.

Diagnosis of liver cancer and cirrhosis by the fluorescence spectra of blood and urine.

Liver cancer or hepato cellular carcinoma (HCC) is a serious malady with only 10% survival rate and is fatal next only to pancreatic cancer. This disease is conventionally detected and diagnosed by ultra sound, CT or MRI scans which are quite expensive. Also the discrimination between cirrhosis and HCC, by these imaging techniques, is poor. The conventional tissue biopsy is quite invasive and painful. In the new diagnostic procedure presented in this paper we have obtained fluorescence emission spectra with excitation at 400 nm and the synchronous emission spectra (Δλ = 10 nm) for a set of blood and urine samples (Normal control N = 25, Liver Malfunction N = 58). Based on the ratio fluorometric parameters, all the three liver maladies (minor inflammation like Hepatitis C, serious diseases like Cirrhosis and hepatoma) could be detected and discriminated with an accuracy of about 80%. Hence this inexpensive, non invasive, optical technique may have significant impact in screening, diagnosis and also prognosis of HCC in large segment of people in the populous Asian countries.

Detection of cancer by optical analysis of body fluids--a single blind study.

This paper pertains to a new technique based on fluorescence emission spectra (FES), and stokes shift spectra (SSS) of blood plasma, acetone extract of cellular fraction, and urine. These samples were collected from 60 cancer patients of different etiology and 60 age adjusted controls for a single blind study. A set of ratio parameters were obtained from the above spectra (FES and SSS of above three sets of samples), based on the relative intensity of biofluorophores like tryptophan, tyrosine, flavin etc. It was found that these biofluorophores go out of proportion for malignancy of any etiolology. The study was done in two phases: calibration and validation. Based on a certain set of ratios obtained by simple statistical analysis, in the calibration phase, the blinded samples of validation phase were spectrally analysed and classified as normal or malignant. The scoring done by independent oncologists (who were not involved in any part of this new technique) yielded an overall sensitivity of 87%, and specificity of 83%. The result indicate that new optical spectroscopic techniques could be a simple, non-invasive protocol for detection of cancers, particularly in symptomatic cases; or for monitoring the post treated cases of cancer.

Fluorescence spectra of blood components for breast cancer diagnosis.

OBJECTIVE: To explore whether fluorescence emission spectroscopy of blood components can differentiate normal from early and advanced stages of breast cancer using stepwise discriminant analysis. MATERIALS AND METHODS: Fluorescence emission spectra were measured for blood components of three different groups: 35 normal controls, 28 with early-stage, and 18 with advanced-stage breast cancer. The data from the spectra were subjected to Fisher's linear discriminant analysis. Classification accuracy, specificity, and sensitivity of the technique were calculated for breast cancer diagnosis. RESULTS: Fluorescence emission spectra of blood components accurately distinguished normal from early-stage and advanced-stage breast cancer in 91.4% of original cases and 90.1% for cross-validated cases. The sensitivity and specificity were 80.4% and 100%, respectively, in distinguishing subjects with breast cancer from normal controls. CONCLUSION: Our statistical evaluation indicates that porphyrin in blood can be used as a reliable tumor marker. Fluorescence emission spectroscopy of blood components and statistical evaluations should be further investigated for a variety of tumors.

Spectrofluorimetric detection of DMBA-induced mouse skin carcinoma.

An attempt has been made to evaluate the normal and cancer blood samples of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mouse skin carcinoma by spectrofluorimetric method. Analysis of acetone extracts of plasma, erythrocyte and erythrocyte membrane showed an alteration around 630 nm when excited at 400 nm by cancer samples, compared to normal samples. The ratio of fluorescent intensity at 530 nm/630 nm was found to be decreased in erythrocyte and plasma and increased in erythrocyte membrane. These changes are not detectable in both hemolysates. It has been suggested that erythrocytes may be the carriers of fluorophors that accumulate in cancer tissue and may be useful in the diagnosis and treatment of malignancies.