***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND Optical coherence tomography ( OCT ) is an evolving optical technology that is capable of delivering real-time , high-resolution signatures of tissue . OBJECTIVES The purpose of this immediate ex vivo prospect i ve clinical study was : ( 1 ) to assess the sensitivity and specificity of OCT on biopsy material in identifying potentially malignant and malignant oral lesions , ( 2 ) to determine the inter-observer agreement in the analysis of specific image parameters , and ( 3 ) to find out the oral epithelial thickness for different pathology groups . MATERIAL S AND METHODS This prospect i ve study involved 125 suspicious oral lesions from 125 patients . The lesions were surgically biopsied and subjected to OCT in the immediate ex vivo phase . Two independent readers ( surgeon and pathologist ) examined the OCT images and assessed several cellular features including keratin layer , epithelial layer , basement membrane and lamina propria , and recorded their findings using special OCT reading score . The sensitivity , specificity and accuracy of OCT  to predict " the future need for surgical biopsy in case of any similar lesion " were calculated . The epithelial thickness was also measured . The degree of agreement between the two readers was recorded . RESULTS The pathological diagnosis revealed that the majority of lesions demonstrated microinvasive carcinomas ( n=43 ) . Forty-one had different degree of dysplasia . Benign oral lesions were less common and included 22 keratosis , 11 non-specific lesions , 6 mucocels and 2 papillomas . Optical coherence tomography achieved a sensitivity of 85 % and a specificity of 78 % in the assessment of oral potentially malignant and malignant disorders . The positive and negative predictive values were 86.5 % and 77.5 % , respectively . The accuracy was 82 % and the kappa coefficient of inter-observer agreement was 0.72 on " the need for biopsy " .  OCT imaging of oral lesions provided valuable information on the oral epithelial thickness . CONCLUSION This study proposes that OCT can accurately identify wide spectrum of oral tissue pathologies . Further studies can assess the role of OCT in evaluating and guiding surgical biopsies and monitoring disease Laser-induced fluorescence at 337-nm excitation was used in vivo to differentiate neoplastic [ cervical intraepithelial neoplasia ( CIN ) ] , nonneoplastic abnormal ( inflammation and human papilloma viral infection ) , and normal cervical tissues . A colposcope ( low-magnification microscope used to view the cervix with reflected light ) was used to identify 66 normal and 49 abnormal ( 5 inflammation , 21 human papilloma virus infection , and 23 CIN ) sites on the cervix in 28 patients . These sites were then interrogated spectroscopically . A two-stage algorithm was developed to diagnose CIN . The first stage differentiated histologically abnormal tissues from colposcopically normal tissues with a sensitivity , specificity , and positive predictive value of 92 % , 90 % , and 88 % , respectively . The second stage differentiated preneoplastic and neoplastic tissues from nonneoplastic abnormal tissues with a sensitivity , specificity , and positive predictive value of 87 % , 73 % , and 74 % , respectively . Spectroscopic differences were consistent with a decrease in the absolute contribution of collagen fluorescence , an increase in the absolute contribution of oxyhemoglobin attenuation , and an increase in the relative contribution of reduced nicotinamide dinucleotide phosphate [ NAD(P)H ] fluorescence as tissue progresses from normal to abnormal in the same patient . These results suggest that in vivo fluorescence spectroscopy of the cervix can be used to diagnose CIN at colposcopy The prognosis for patients with oral squamous cell carcinoma remains poor despite advances in multimodal treatment concepts . Early diagnosis and treatment is the key to improved patient survival . A device ( VELscope ) that uses autofluorescence technology , allowing direct fluorescence visualization of the oral cavity , might be a useful tool for oral cancer detection or as an adjunct to st and ard clinical examination . A total of 289 patients with oral premalignant lesions were r and omly divided into two groups for clinical examination of precancerous oral lesions . In group 1 , 166 patients were examined conventionally with white light , and in group 2 , 123 patients were examined with the autofluorescence visualization device ( VELscope ) in addition to the white light examination . Biopsies were obtained from all suspicious areas identified in both examination groups ( n=52 ) . In the first step , baseline characteristics of the two groups ( only white light vs. white light and VELscope ) were compared to exclude selection bias . In the second step , for the group examined with white light and VELscope ( 123 patients ) , the diagnostic strategies were compared with regard to sensitivity and specificity using biopsy as the gold st and ard . The results showed that using the VELscope leads to higher sensitivity ( 100 % instead of 17 % ) , but to lower specificity ( 74 % instead of 97 % ) . Thus , we can conclude that the VELscope is a useful new diagnostic device for detection of oral cancer diseases Early diagnosis of oral mucosal lesions has been advocated as a means of improving outcomes of cancer therapy . Improved visualization of mucosal lesions may aid in diagnosis by guiding tissue sampling or referral . This multicenter study reports the effect of chemiluminescent light ( ViziLite ) upon visualization of mucosal lesions . The chemiluminescent light did not appear to improve visualization of red lesions , but white lesions and lesions that were both red and white showed enhanced brightness and sharpness These comments and observations are based on 25 years of clinical practice in oncology , and prospect i ve research studies of oropharyngeal squamous carcinoma in high-risk population s ; the review of innumerable publications related to squamous carcinoma ( most of which have usually been based on retrospective analysis of data or anecdotal information ) and my observations , as a clinician and a patient , of the behavior , beliefs , and practice of dental and medical clinicians . Although the oral cavity and oropharynx are as easily accessible for visualization , as is skin , and the population at high risk ( development of squamous cancers of these sites has been identi ® ed in a multitude of studies in the USA and Western Europe ) , early diagnosis has not been forthcoming with the result ant lack of increase in 5-year survival rates when compared to cancers of other sites . It is with dismay I observe that over the last 20±30 years , early diagnosis and survival rates for cancers of the breast , colon , prostate and melanoma have increased considerably , due primarily to an increase in early detection . However , survival rates for cancers of the oral cavity and oropharynx have remained constant during this period at approximately 40±50 % with a small decrease in the black population . Paradoxically , even though the mucosa of the colon is internal and requires endocscopic examination for evaluation , 36 % of colon cancers ( US ) are localized when diagnosed , identical to the number of localized oral/ oropharyngeal ( O/OP ) cancers diagnosed . Most of the O/OP cancers at time of diagnosis are symptomatic late-stage disease with at least 50 % revealing regional cervical metastases . Survival is poor . We have an overwhelming responsibility to ameliorate this situation . I believe there are two areas of concern that are greatly responsible for this de ® ciency in diagnosis . The ® rst deals with the split professional responsibility attendant to this anatomical region . Dentists who are , supposedly , in the ® rst line of defense and are responsible for the early diagnosis of these cancers have a con icted position . Their training , education , and experience in dealing with cancer as a concept and in practical terms is somewhat limited . The emphasis in their education and practice is primarily related to restoration and amelioration of dental and hard tissue problems . Although at home in the oral cavity and much more capable of performing a soft tissue examination than their physician counterparts , they re exly respond to the restoration mode . My experience as a patient , clinician , teacher and casual observer con ® rms that few generalists or specialists evaluate the high-risk sites of occurrence as part of the st and ard dental examination . Literature disseminated by major dental organizations , government , non-pro ® t , dental schools , etc . , list programs and lectures in a variety of dental spheres . Cancer infrequently is listed as a topic . The physician , on the other h and , although trained to be concerned with oncology , has minimal or no training in the oral cavity . Sections of O/OP cancer and examination of this anatomical region in medical texts are woefully inadequate . Related lectures for medical students and trainees are few . A physician using a tongue blade with a pen ashlight for illumination , requesting the patient to say ` ` ah ' ' , can not possibly highlight the minimal mucosal changes which signify early asymptomatic squamous cancer . Among medical Conventional screening practice for oral lesions involves visual scrutiny of the oral tissues with the naked eye under projected inc and escent or halogen illumination . Visualisation is the principal strategy used to assess patients ' lesions at risk for malignant transformation ; hence , any procedure which highlights such lesions should aid the clinician . The aim of this pilot study was to examine the efficacy of acetic acid wash and chemiluminescent light ( ViziLite ) in enhancing visualisation of oral mucosal white lesions , and its ability to highlight malignant and potentially malignant lesions .  Fifty five patients referred for assessment of an oral white lesion , were prospect ively screened with ViziLite , and an incisional scalpel biopsy performed for a definitive diagnosis . The size , location , ease of visibility , border distinctness , and presence of satellite lesions were recorded . The ViziLite tool enhanced intra-oral visualisation of 26 white lesions . Indeed , all lesions appeared " aceto-white " , regardless of the definitive diagnosis . Examination of the oral tissues with ViziLite illumination did not change the provisional diagnosis , nor alter the biopsy site .  ViziLite illumination does not discriminate between keratotic , inflammatory , malignant or potentially malignant oral mucosal white lesions and thus , a high index of suspicion , expert clinical judgment , and scalpel biopsy are still essential for proper patient care OBJECTIVE AND STUDY DESIGN Several noninvasive adjunctive methods have been proposed for identification of potentially malignant mucosa lesions . The VELscope is an optical device for detecting spatial changes in mucosa autofluorescence caused by premalignant lesions in conjunction with an intraoral exam . The aim of our prospect i ve study was to correlate loss of autofluorescence from undiagnosed mucosa lesions with histology . RESULTS In total 64 patients considered at risk for squamous cell carcinoma ( 20 had previous OSCC ) were included in the study . Regions with fluorescence visualization loss were considered as malignant or dysplastic . All patients underwent  biopsy  after VELscope examination . In 22 patients ( 34.4 % ) a loss of autofluorescence indicating a squamous intraepithelial neoplasia ( SIN ) or malignant mucosal lesion was detected . The sensitivity of identification of malignant and dysplastic areas with the VELscope was 100 % and the specificity was 80.8 % , respectively , compared with histology as gold st and ard . The positive predictive value was 54.5 % and the negative predictive value was 100 % respectively . CONCLUSION Evaluation of autofluorescence imaging with VELscope can assist in the identification of malignant and potentially malignant oral lesions from normal mucosa in high-risk patients but does not help discriminating benign lesions from malignant or premalignant mucosal conditions BACKGROUND Oral cancer is common in men from developing countries , and is increased by tobacco and alcohol use . We aim ed to assess the effect of visual screening on oral cancer mortality in a cluster-r and omised controlled trial in India . METHODS Of the 13 clusters chosen for the study , seven were r and omised to three rounds of oral visual inspection by trained health workers  at 3-year intervals and six to a control group during 1996 - 2004 , in Triv and rum district , Kerala , India . Healthy participants aged 35 years and older were eligible for the study . Screen-positive people were referred for clinical examination by doctors , biopsy , and treatment . Outcome measures were survival , case fatality , and oral cancer mortality . Oral cancer mortality in the study groups was analysed and compared by use of cluster analysis . Analysis was by intention to treat . FINDINGS Of the 96,517 eligible participants in the intervention group , 87,655 ( 91 % ) were screened at least once , 53,312 ( 55 % ) twice , and 29,102 ( 30 % ) three times . Of the 5145 individuals who screened positive , 3218 ( 63 % ) complied with referral . 95,356 eligible participants in the control group received st and ard care . 205 oral cancer cases and 77 oral cancer deaths were recorded in the intervention group compared with 158 cases and 87 deaths in the control group ( mortality rate ratio 0.79 [ 95 % CI 0.51 - 1.22 ] ) . 70 oral cancer deaths took place in users of tobacco or alcohol 
    Output:
    
Chemiluminescence shows good sensitivity at detecting any OPMDs and oral cancer .
However , it preferentially detects leukoplakia and may fail to spot red patches .
The additive use of toluidine blue may improve specificity .
Tissue autofluorescence is sensitive at detecting white , red and white and red patches , and the area of fluorescence visualisation loss ( FVL ) often extends beyond the clinical ly visible lesion .
However , in addition to OPMDs , VELScope may detect erythematous lesions of benign inflammation result ing in false-positive test results .