Metastatic serous endometrial carcinoma to the ureter.

Metastatic endometrial carcinoma involving the renal parenchyma has been reported. However, ureteral metastasis is exceedingly rare. Here we describe what we believe to be the first case report of metastatic endometrial serous carcinoma to the ureteral and renal pelvic urothelium. The patient is a 68 year old female diagnosed with endometrial serous carcinoma three years prior to presentation who was found to have metastatic disease within the right ureter and retroperitoneal lymph nodes. Following a complete response in the lymph nodes to chemotherapy, she was treated with robot-assisted right nephroureterectomy for residual, isolated PET-avid right ureteral metastasis.

Correction: Proteogenomic Characterization of Ovarian HGSC Implicates Mitotic Kinases, Replication Stress in Observed Chromosomal Instability.

[This corrects the article PMC7289043.].

Proteogenomic Characterization of Ovarian HGSC Implicates Mitotic Kinases, Replication Stress in Observed Chromosomal Instability.

In the absence of a dominant driving mutation other than uniformly present TP53 mutations, deeper understanding of the biology driving ovarian high-grade serous cancer (HGSC) requires analysis at a functional level, including post-translational modifications. Comprehensive proteogenomic and phosphoproteomic characterization of 83 prospectively collected ovarian HGSC and appropriate normal precursor tissue samples (fallopian tube) under strict control of ischemia time reveals pathways that significantly differentiate between HGSC and relevant normal tissues in the context of homologous repair deficiency (HRD) status. In addition to confirming key features of HGSC from previous studies, including a potential survival-associated signature and histone acetylation as a marker of HRD, deep phosphoproteomics provides insights regarding the potential role of proliferation-induced replication stress in promoting the characteristic chromosomal instability of HGSC and suggests potential therapeutic targets for use in precision medicine trials.

Endometrial Cancer: Is This a New Disease?

The incidence of endometrial cancer is increasing, and the age of onset is younger than in prior years. Although endometrial cancer still occurs more commonly in older women, for whom the mortality rate is increasing, it also is being diagnosed in younger and younger women. The underlying cause of the increase in incidence is the epidemic of obesity and the resulting hyperinsulinemia. Conservative treatment may be indicated for younger women who wish to retain their fertility. Lifestyle modifications such as diet and exercise can modulate the risk of developing endometrial cancer as well as prevent recurrence and other comorbidities associated with obesity.

3D texture analysis for classification of second harmonic generation images of human ovarian cancer.

Remodeling of the collagen architecture in the extracellular matrix (ECM) has been implicated in ovarian cancer. To quantify these alterations we implemented a form of 3D texture analysis to delineate the fibrillar morphology observed in 3D Second Harmonic Generation (SHG) microscopy image data of normal (1) and high risk (2) ovarian stroma, benign ovarian tumors (3), low grade (4) and high grade (5) serous tumors, and endometrioid tumors (6). We developed a tailored set of 3D filters which extract textural features in the 3D image sets to build (or learn) statistical models of each tissue class. By applying k-nearest neighbor classification using these learned models, we achieved 83-91% accuracies for the six classes. The 3D method outperformed the analogous 2D classification on the same tissues, where we suggest this is due the increased information content. This classification based on ECM structural changes will complement conventional classification based on genetic profiles and can serve as an additional biomarker. Moreover, the texture analysis algorithm is quite general, as it does not rely on single morphological metrics such as fiber alignment, length, and width but their combined convolution with a customizable basis set.

Coregistered photoacoustic and ultrasound imaging and classification of ovarian cancer: ex vivo and in vivo studies.

Most ovarian cancers are diagnosed at advanced stages due to the lack of efficacious screening techniques. Photoacoustic tomography (PAT) has a potential to image tumor angiogenesis and detect early neovascular changes of the ovary. We have developed a coregistered PAT and ultrasound (US) prototype system for real-time assessment of ovarian masses. Features extracted from PAT and US angular beams, envelopes, and images were input to a logistic classifier and a support vector machine (SVM) classifier to diagnose ovaries as benign or malignant. A total of 25 excised ovaries of 15 patients were studied and the logistic and SVM classifiers achieved sensitivities of 70.4 and 87.7%, and specificities of 95.6 and 97.9%, respectively. Furthermore, the ovaries of two patients were noninvasively imaged using the PAT/US system before surgical excision. By using five significant features and the logistic classifier, 12 out of 14 images (86% sensitivity) from a malignant ovarian mass and all 17 images (100% specificity) from a benign mass were accurately classified; the SVM correctly classified 10 out of 14 malignant images (71% sensitivity) and all 17 benign images (100% specificity). These initial results demonstrate the clinical potential of the PAT/US technique for ovarian cancer diagnosis.

Ovarian Cancer Cell Adhesion/Migration Dynamics on Micro-Structured Laminin Gradients Fabricated by Multiphoton Excited Photochemistry.

Haptotaxis, i.e., cell migration in response to adhesive gradients, has been previously implicated in cancer metastasis. A better understanding of cell migration dynamics and their regulation could ultimately lead to new drug targets, especially for cancers with poor prognoses, such as ovarian cancer. Haptotaxis has not been well-studied due to the lack of biomimetic, biocompatible models, where, for example, microcontact printing and microfluidics approaches are primarily limited to 2D surfaces and cannot produce the 3D submicron features to which cells respond. Here we used multiphoton excited (MPE) phototochemistry to fabricate nano/microstructured gradients of laminin (LN) as 2.5D models of the ovarian basal lamina to study the haptotaxis dynamics of a series of ovarian cancer cells. Using these models, we found that increased LN concentration increased migration speed and also alignment of the overall cell morphology and their cytoskeleton along the linear axis of the gradients. Both these metrics were enhanced on LN compared to BSA gradients of the same design, demonstrating the importance of both topographic and ECM cues on the adhesion/migration dynamics. Using two different gradient designs, we addressed the question of the roles of local concentration and slope and found that the specific haptotactic response depends on the cell phenotype and not simply the gradient design. Moreover, small changes in concentration strongly affected the migration properties. This work is a necessary step in studying haptotaxis in more complete 3D models of the tumor microenvironment for ovarian and other cancers.

Texture analysis applied to second harmonic generation image data for ovarian cancer classification.

Remodeling of the extracellular matrix has been implicated in ovarian cancer. To quantitate the remodeling, we implement a form of texture analysis to delineate the collagen fibrillar morphology observed in second harmonic generation microscopy images of human normal and high grade malignant ovarian tissues. In the learning stage, a dictionary of "textons"­frequently occurring texture features that are identified by measuring the image response to a filter bank of various shapes, sizes, and orientations­is created. By calculating a representative model based on the texton distribution for each tissue type using a training set of respective second harmonic generation images, we then perform classification between images of normal and high grade malignant ovarian tissues. By optimizing the number of textons and nearest neighbors, we achieved classification accuracy up to 97% based on the area under receiver operating characteristic curves (true positives versus false positives). The local analysis algorithm is a more general method to probe rapidly changing fibrillar morphologies than global analyses such as FFT. It is also more versatile than other texture approaches as the filter bank can be highly tailored to specific applications (e.g., different disease states) by creating customized libraries based on common image features.

Inhibition of DNA methyltransferases, histone deacetylases and lysine-specific demethylase-1 suppresses the tumorigenicity of the ovarian cancer ascites cell line SKOV3.

Ovarian cancer is one of the most lethal female malignancies and epigenetic abnormalities are thought to play a vital role in the pathogenesis, development and progression of ovarian cancer. Our goal was to investigate whether the combination of trichostatin A (TSA) and 5-aza-2'-deoxycytidine (decitabine) was superior to single agent on tumorigenicity of ovarian cancer cells. We found that tumorigenicity and metastasis of SKOV3 cells were significantly suppressed by the combination of TSA and decitabine in xenograft mouse models. Migration capacity was markedly suppressed through the induction of E-cadherin and suppression of N-cadherin when treated with TSA and decitabine. Invasion was also suppressed at least partially through inhibition of MMP-2 and MMP-9 with the combined treatment. The combination drugs markedly inhibited spheroid formation and significantly impaired migration and invasion capacity of spheroid derived cells through inhibition of Twist, N-cadherin, MMP-2, MMP-9 and induction of E-cadherin. Epigenetically, the activity of DNA methyltransferases (DNMTs) and histone deacetylases (HDACs) were markedly inhibited when TSA was used in combination with decitabine, especially the expression of DNMT3A/3B and HDAC1/2. Acetylation of histone H3 and H4 were more markedly stimulated with the combination than with either agent alone. The expression level of lysine-specific demethylase-1 (LSD1) was also suppressed. The transcription activity marker dimethylated-H3K4 was induced, but the dimethylated-H3K9 was suppressed by exposure to the combined drugs. These results suggest that the combination of TSA and decitabine significantly suppresses tumorigenicity by inhibiting migration and invasion of ovarian cancer cells via regulating the expression of the cadherins and MMPs, which may be epigenetically regulated by DNA methylation and histone modification.

7,12-dimethylbenz[a]anthracene-induced malignancies in a mouse model of menopause.

Ovarian cancer has a high mortality rate because there are few symptoms in early disease development. The incidence of ovarian cancer increases in women after menopause. Understanding early events in this disease can best be achieved by using animal models. Therefore, the objective of this study was to develop and track the onset of ovarian tumorigenesis in mice mimicking characteristics of postmenopausal epithelial cancer in women. Female B6C3F1 mice (age, 28 d) received 4-vinylcyclohexene diepoxide (VCD, 160 mg/kg IV daily for 20 d) to cause ovarian failure. Four months after VCD treatment, via surgical intervention, each mouse received a single injection of 7,12-dimethylbenz[a]anthracene (DMBA) or vehicle control (sesame oil) under the bursa of the right ovary to cause ovarian neoplasms. The experimental groups were untreated controls (Con-Con), DMBA-treatment only (Con-DMBA), VCD treatment only (VCD-Con), and VCD+DMBA-treated (VCD+DMBA) mice. At 3, 5, 7, and 9 mo after DMBA injection, ovaries were collected for histologic and immunohistochemical evaluation. No tumors developed in Con-Con mice. All VCD-treated mice (with or without DMBA) exhibited ovarian failure. Mice that received both VCD and DMBA exhibited tumors at 3 mo (50%), 5 mo (14%), 7 mo (90%), and 9 mo (57%) after DMBA treatment; 31% of the tumors were epithelial in origin. Our findings confirm that inducing ovarian tumors in mice by chemical means is an effective method for studying early stages of tumor development that may be relevant to epithelial ovarian cancers that arise in postmenopausal women.

Two-photon excited fluorescence imaging of endogenous contrast in a mouse model of ovarian cancer.

BACKGROUND AND OBJECTIVE: Ovarian cancer has an extremely high mortality rate resulting from poor understanding of the disease. In order to aid understanding of disease etiology and progression, we identify the endogenous fluorophores present in a mouse model of ovarian cancer and describe changes in fluorophore abundance and distribution with age and disease. STUDY DESIGN/MATERIALS AND METHODS: A mouse model of ovarian cancer was created by dosing with 4-vinylcyclohexene diepoxide, which induces follicular apoptosis (simulating menopause), and 7,12-dimethylbenz[a]anthracene, a known carcinogen. Imaging of ovarian tissue was completed ex vivo with a multiphoton microscope using excitation wavelength of 780 nm and emission collection from 405 to 505 nm. Two-photon excited fluorescence images and corresponding histologic sections with selective stains were used to identify endogenous fluorophores. RESULTS: The majority of collected fluorescence emission was attributed to NADH and lipofuscin, with additional contributions from collagen and elastin. Dim cellular fluorescence from NADH did not show observable changes with age. Changes in ovarian morphology with disease development frequently caused increased fluorescence contributions from collagen and adipose tissue-associated NADH. Lipofuscin fluorescence was much brighter than NADH fluorescence and increased as a function of both age and disease. CONCLUSIONS: Our finding of NADH fluorescence patterns similar to that seen previously in human ovary, combined with the observation of lipofuscin accumulation with age and disease also seen in human organs, suggests that the findings from this model may be relevant to human ovarian disease. Increased lipofuscin fluorescence might be used as an indicator of disease in the ovary and this finding warrants further study.

Analysis of second-harmonic-generation microscopy in a mouse model of ovarian carcinoma.

Second-harmonic-generation (SHG) imaging of mouse ovaries ex vivo was used to detect collagen structure changes accompanying ovarian cancer development. Dosing with 4-vinylcyclohexene diepoxide and 7,12-dimethylbenz[a]anthracene resulted in histologically confirmed cases of normal, benign abnormality, dysplasia, and carcinoma. Parameters for each SHG image were calculated using the Fourier transform matrix and gray-level co-occurrence matrix (GLCM). Cancer versus normal and cancer versus all other diagnoses showed the greatest separation using the parameters derived from power in the highest-frequency region and GLCM energy. Mixed effects models showed that these parameters were significantly different between cancer and normal (P<0.008). Images were classified with a support vector machine, using 25% of the data for training and 75% for testing. Utilizing all images with signal greater than the noise level, cancer versus not-cancer specimens were classified with 81.2% sensitivity and 80.0% specificity, and cancer versus normal specimens were classified with 77.8% sensitivity and 79.3% specificity. Utilizing only images with greater than of 75% of the field of view containing signal improved sensitivity and specificity for cancer versus normal to 81.5% and 81.1%. These results suggest that using SHG to visualize collagen structure in ovaries could help with early cancer detection.

Parallel factor analysis of ovarian autofluorescence as a cancer diagnostic.

BACKGROUND AND OBJECTIVES: Endogenous fluorescence from certain amino acids, structural proteins, and enzymatic co-factors in tissue is altered by carcinogenesis. We evaluate the potential of these changes in fluorescence to predict a diagnosis of malignancy and to estimate the risk of developing ovarian cancer. STUDY DESIGN/MATERIALS AND METHODS: Ovarian biopsies were interrogated over 270-550 nm excitation and fluorescence was collected from 290 to 700 nm. Two hundred forty-nine measurements were performed on 49 IRB-consented patients undergoing oophorectomy. Data are analyzed using parallel factor analysis to determine excitation and emission spectra of the underlying fluorophores that contribute to the total detected fluorescence intensity. RESULTS: Using multivariate normal distribution fits and cross-validation techniques, sensitivity and specificity of 88% and 93%, respectively, are achieved when classifying malignant samples versus others, while 88% and 80%, respectively, are achieved when classifying normal post-menopausal patients as being either at high- or low-risk of developing ovarian cancer based on their personal and family history of cancer. Performance of classifying cancer increases when the normal group does not include benign neoplasm and endometriosis samples. Performance of high- versus low-risk classification decreases when normal samples include both pre- and post-menopausal women. Excitation over 270-400 and 380-560 nm, respectively, have the best diagnostic performance for cancer detection and risk-status assessment. CONCLUSIONS: Assessing the endogenous fluorescence could be useful in screening women at increased risk of developing ovarian cancer.

Simultaneous optical coherence tomography and laser induced fluorescence imaging in rat model of ovarian carcinogenesis.

Determining if an ovarian mass is benign or malignant is an ongoing clinical challenge. The development of reliable animal models provides means to evaluate new diagnostic tools to more accurately determine if an ovary has benign or malignant features. Although sex cord-stromal tumors (SCST) account for 0.1­0.5% of ovarian malignancies, they have similar appearances to more aggressive epithelial cancers and can serve as a prototype for developing better diagnostic methods for ovarian cancer. Optical coherence tomography (OCT) and laser-induced fluorescence (LIF) spectroscopy are non-destructive optical imaging modalities. OCT provides architectural cross-sectional images at near histological resolutions and LIF provides biochemical information. We utilize combined OCT-LIF to image ovaries in post-menopausal ovarian carcinogenesis rat models, evaluating normal cyclic, acyclic and neoplastic ovaries. Eighty-three female Fisher rats were exposed to combinations of control sesame oil, 4-vinyl cyclohexene diepoxide (VCD) to induce ovarian failure,and/or 7,12-dimethylbenz[a]anthracene (DMBA) to induce carcinogenesis. Three or five months post-treatment, 162 ovaries were harvested and imaged with OCT-LIF: 40 cyclic, 105 acyclic and 17 SCST. OCT identified various follicle stages,corpora lutea (CL), CL remnants, epithelial invaginations/inclusions and allowed for characterization of both cystic and solid SCST. Signal attenuation comparisons between CL and solid SCST revealed statistically significant increases in attenuation among CL. LIF characterized spectral differences in cyclic, acyclic and neoplastic ovaries attributed to collagen, NADH/FAD and hemoglobin absorption. We present combined OCT-LIF imaging in a rat ovarian carcinogenesis model, providing preliminary criteria for normal cyclic, acyclic and SCST ovaries which support the potential of OCT-LIF for ovarian imaging.

Overexpression of tumor vascular endothelial growth factor A may portend an increased likelihood of progression in a phase II trial of bevacizumab and erlotinib in resistant ovarian cancer.

PURPOSE: This phase II trial evaluated bevacizumab plus erlotinib in platinum-resistant ovarian cancer; exploratory biomarker analyses, including that of tumor vascular endothelial growth factor A (VEGF-A), were also done. EXPERIMENTAL DESIGN: Forty heavily pretreated patients received erlotinib (150 mg/d orally) and bevacizumab (10 mg/kg i.v.) every 2 weeks until disease progression. Primary end points were objective response rate and response duration; secondary end points included progression-free survival (PFS), toxicity, and correlations between angiogenic protein levels, toxicity, and efficacy. RESULTS: Grade 3 toxicities included skin rash (n = 6), diarrhea (n = 5), fatigue (n = 4), and hypertension (n = 3). Grade 4 toxicities were myocardial infarction (n = 1) and nasal septal perforation (n = 1). Only one grade 3 fistula and one grade 2 bowel perforation were observed. Nine (23.1%) of 39 evaluable patients had a response (median duration, 36.1+ weeks; one complete response), and 10 (25.6%) patients achieved stable disease, for a disease control rate of 49%. Median PFS was 4 months, and 6-month PFS was 30.8%. Biomarker analyses identified an association between tumor cell VEGF-A expression and progression (P = 0.03); for every 100-unit increase in the VEGF-A score, there was a 3.7-fold increase in the odds of progression (95% confidence interval, 1.1-16.6). CONCLUSIONS: Bevacizumab plus erlotinib in heavily pretreated ovarian cancer patients was clinically active and well tolerated. Erlotinib did not seem to contribute to efficacy. Our study raises the intriguing possibility that high levels of tumor cell VEGF-A, capable of both autocrine and paracrine interactions, are associated with resistance to bevacizumab, emphasizing the complexity of the tumor microenvironment.

Clinical research device for ovarian cancer detection by optical spectroscopy in the ultraviolet C-visible.

Early detection of ovarian cancer could greatly increase the likelihood of successful treatment. However, present detection techniques are not very effective, and symptoms are more commonly seen in later stage disease. Amino acids, structural proteins, and enzymatic cofactors have endogenous optical properties influenced by precancerous changes and tumor growth. We present the technical details of an optical spectroscopy system used to quantify these properties. A fiber optic probe excites the surface epithelium (origin of 90% of cases) over 270 to 580 nm and collects fluorescence and reflectance at 300 to 800 nm with four or greater orders of magnitude instrument to background suppression. Up to four sites per ovary are investigated on patients giving consent to oophorectomy and the system's in vivo optical evaluation. Data acquisition is completed within 20 s per site. We illustrate design, selection, and development of the components used in the system. Concerns relating to clinical use, performance, calibration, and quality control are addressed. In the future, spectroscopic data will be compared with histological biopsies from the corresponding tissue sites. If proven effective, this technique can be useful in screening women at high risk of developing ovarian cancer to determine whether oophorectomy is necessary.

Alterations of the extracellular matrix in ovarian cancer studied by Second Harmonic Generation imaging microscopy.

BACKGROUND: Remodeling of the extracellular matrix (ECM) has been implicated in ovarian cancer, and we hypothesize that these alterations may provide a better optical marker of early disease than currently available imaging/screening methods and that understanding their physical manifestations will provide insight into invasion. METHODS: For this investigation we use Second Harmonic Generation (SHG) imaging microcopy to study changes in the structure of the ovarian ECM in human normal and malignant ex vivo biopsies. This method directly visualizes the type I collagen in the ECM and provides quantitative metrics of the fibrillar assembly. To quantify these changes in collagen morphology we utilized an integrated approach combining 3D SHG imaging measurements and bulk optical parameter measurements in conjunction with Monte Carlo simulations of the experimental data to extract tissue structural properties. RESULTS: We find the SHG emission attributes (directionality and relative intensity) and bulk optical parameters, both of which are related to the tissue structure, are significantly different in the tumors in a manner that is consistent with the change in collagen assembly. The normal and malignant tissues have highly different collagen fiber assemblies, where collectively, our findings show that the malignant ovaries are characterized by lower cell density, denser collagen, as well as higher regularity at both the fibril and fiber levels. This further suggests that the assembly in cancer may be comprised of newly synthesized collagen as opposed to modification of existing collagen. CONCLUSIONS: Due to the large structural changes in tissue assembly and the SHG sensitivity to these collagen alterations, quantitative discrimination is achieved using small patient data sets. Ultimately these measurements may be developed as intrinsic biomarkers for use in clinical applications.

Adhesion and migration of ovarian cancer cells on crosslinked laminin fibers nanofabricated by multiphoton excited photochemistry.

Ovarian cancer is the deadliest gynecological cancer, which may arise in part due to the concurrent invasion and metastasis of high grade tumors. It is thus crucial to gain insight into the adhesion and migration mechanisms in vivo, as this may ultimately lead to new treatment/detection options. To explore this possibility, we have used multiphoton excited photochemistry (MPE) to synthesize models of the ovarian basal lamina consisting of crosslinked laminin nanofibers to quantify the adhesion/migration dynamics. The nanostructured laminin patterns permit the systematic comparison of total migration, directed migration, adhesion, and morphology of "normal" immortalized human ovarian epithelial cells (IOSE) and three lines of varying metastatic potential (OVCA433, SKOV-3.ip1, and HEY-1 cells). We find that the migration of all the cell lines is directed by the crosslinked fibers, and that the contact guidance enhances the total migration rates relative to monolayers. These rates increase with increasing metastatic potential, and the more invasive cells are less rigid and more weakly adhered to the nanofibers. The extent of directed migration also depends on the cell polarity and focal adhesion expression. For the invasive cells, these findings are similar to the integrin-independent ameboid-like migration seen for polar cells in collagen gels. Collectively, the results suggest that contact mediated migration as well as decreased adhesion may be operative in metastasis of ovarian cancer in vivo.

Laparoscopic optical coherence tomography imaging of human ovarian cancer.

OBJECTIVES: Ovarian cancer is the fourth leading cause of cancer-related death among women in the US largely due to late detection secondary to unreliable symptomology and screening tools without adequate resolution. Optical coherence tomography (OCT) is a recently emerging imaging modality with promise in ovarian cancer diagnostics, providing non-destructive subsurface imaging at imaging depths up to 2 mm with near-histological grade resolution (10-20 microm). In this study, we developed the first ever laparoscopic OCT (LOCT) device, evaluated the safety and feasibility of LOCT, and characterized the microstructural features of human ovaries in vivo. METHODS: A custom LOCT device was fabricated specifically for laparoscopic imaging of the ovaries in patients undergoing oophorectomy. OCT images were compared with histopathology to identify preliminary architectural imaging features of normal and pathologic ovarian tissue. RESULTS: Thirty ovaries in 17 primarily peri- or post-menopausal women were successfully imaged with LOCT: 16 normal, 5 endometriosis, 3 serous cystadenoma, and 4 adenocarcinoma. Preliminary imaging features developed for each category reveal qualitative differences in the homogeneous character of normal post-menopausal ovary, the ability to image small subsurface inclusion cysts, and distinguishable features for endometriosis, cystadenoma, and adenocarcinoma. CONCLUSIONS: We present the development and successful implementation of the first laparoscopic OCT probe. Comparison of OCT images and corresponding histopathology allowed for the description of preliminary microstructural features for normal ovary, endometriosis, and benign and malignant surface epithelial neoplasms. These results support the potential of OCT both as a diagnostic tool and an imaging modality for further evaluation of ovarian cancer pathogenesis.

Computer-aided identification of ovarian cancer in confocal microendoscope images.

The confocal microendoscope is an instrument for imaging the surface of the human ovary. Images taken with this instrument from normal and diseased tissue show significant differences in cellular distribution. A real-time computer-aided system to facilitate the identification of ovarian cancer is introduced. The cellular-level structure present in ex vivo confocal microendoscope images is modeled as texture. Features are extracted based on first-order statistics, spatial gray-level-dependence matrices, and spatial-frequency content. Selection of the features is performed using stepwise discriminant analysis, forward sequential search, a nonparametric method, principal component analysis, and a heuristic technique that combines the results of these other methods. The selected features are used for classification, and the performance of various machine classifiers is compared by analyzing areas under their receiver operating characteristic curves. The machine classifiers studied included linear discriminant analysis, quadratic discriminant analysis, and the k-nearest-neighbor algorithm. The results suggest it is possible to automatically identify pathology based on texture features extracted from confocal microendoscope images and that the machine performance is superior to that of a human observer.