At a workshop coordinated by the WHO Collaborating Centre for Oral Cancer and Precancer in the UK issues related to terminology, definitions and classification of oral precancer were discussed by an expert group The consensus views of the Working Group are presented here The term, 'potentially malignant disorders', was recommended to refer to precancer as it conveys that not all disorders described under this term may transform into cancer Critically evaluating all definitions proposed so far for oral leukoplakia, the Working Group agreed that the term leukoplakia should be used to recognize 'white plaques of questionable risk having excluded (other) known diseases or disorders that carry no increased risk for cancer' An outline was proposed for diagnosing oral leukoplakia that will prevent other oral white disorders being misclassified as leukoplakia The Working Group discussed the caveats involved in the current use of terminology and classification of oral potentially malignant disorders, deficiencies of these complex systems, and how they have evolved over the past several decades The terminology presented in this report reflects our best understanding of multi-step carcinogenesis in the oral mucosa, and aspires to engender consistency in use

https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1600-0714.2007.00582.x

Nomenclature and classification of potentially malignant disorders of the oral mucosa

In the United States, cancers of the oral cavity and oropharynx represent approximately three percent of all malignancies in men and two percent of all malignancies in women. The American Cancer Society estimates that 28,900 new cases of oral cancer will be diagnosed in 2002, and nearly 7,400 people will die from this disease. Over 90 percent of these tumors are squamous cell carcinomas, which arise from the oral mucosal lining. In spite of the ready accessibility of the oral cavity to direct examination, these malignancies still are often not detected until a late stage, and the survival rate for oral cancer has remained essentially unchanged over the past three decades. The purpose of this article is to review the clinical features of oral cancer and premalignant oral lesions, with an emphasis on early detection.

/pdf/oral-cancer-and-precancerous-lesions-1ae8yh9kz7.pdf

Oral cancer and precancerous lesions.

Two hundred fifty-seven patients with oral leukoplakia were studied and followed for an average period of 7.2 years. All lesions were more than one cm in size and had been present and observed for a minimum of 6 months. Of the initial biopsies, 235 revealed a benign hyperkeratosis and 22 others contained some degree of epithelial dysplasia. Seventy-three percent of the patients used tobacco, with cigarette usage being the predominant form. Forty-five patients (17.5%) subsequently developed squamous carcinomas in the hyperkeratotic epithelial site in an average time of 8.1 years. Eight of these malignant transformations came from patients who originally had epithelial dysplasia. High risks for malignant transformation also included non-smoking patients, the clinical presence of erythroplasia (erythroleukoplakia), and a clinical verrucous-papillary hyperkeratotic pattern. Duration of the leukoplakia progressively increased the total number of malignant transformations, with the largest rate occurring in the second year. This study confirms that oral leukoplakia is a precancerous lesion and that certain characteristics indicate greater risks and warrant consideration of more aggressive management.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/1097-0142%2819840201%2953%3A3%3C563%3A%3AAID-CNCR2820530332%3E3.0.CO%3B2-F

Oral leukoplakia and malignant transformation. A follow-up study of 257 patients.

Background
Lay health workers (LHWs) are widely used to provide care for a broad range of health issues. Little is known, however, about the effectiveness of LHW interventions.

Objectives
To assess the effects of LHW interventions in primary and community health care on maternal and child health and the management of infectious diseases.

Search methods
For the current version of this review we searched The Cochrane Central Register of Controlled Trials (including citations uploaded from the EPOC and the CCRG registers) (The Cochrane Library 2009, Issue 1 Online) (searched 18 February 2009); MEDLINE, Ovid (1950 to February Week 1 2009) (searched 17 February 2009); MEDLINE In-Process & Other Non-Indexed Citations, Ovid (February 13 2009) (searched 17 February 2009); EMBASE, Ovid (1980 to 2009 Week 05) (searched 18 February 2009); AMED, Ovid (1985 to February 2009) (searched 19 February 2009); British Nursing Index and Archive, Ovid (1985 to February 2009) (searched 17 February 2009); CINAHL, Ebsco 1981 to present (searched 07 February 2010); POPLINE (searched 25 February 2009); WHOLIS (searched 16 April 2009); Science Citation Index and Social Sciences Citation Index (ISI Web of Science) (1975 to present) (searched 10 August 2006 and 10 February 2010). We also searched the reference lists of all included papers and relevant reviews, and contacted study authors and researchers in the field for additional papers.

Selection criteria
Randomised controlled trials of any intervention delivered by LHWs (paid or voluntary) in primary or community health care and intended to improve maternal or child health or the management of infectious diseases. A 'lay health worker' was defined as any health worker carrying out functions related to healthcare delivery, trained in some way in the context of the intervention, and having no formal professional or paraprofessional certificate or tertiary education degree. There were no restrictions on care recipients.

Data collection and analysis
Two review authors independently extracted data using a standard form and assessed risk of bias. Studies that compared broadly similar types of interventions were grouped together. Where feasible, the study results were combined and an overall estimate of effect obtained.

Main results
Eighty-two studies met the inclusion criteria. These showed considerable diversity in the targeted health issue and the aims, content, and outcomes of interventions. The majority were conducted in high income countries (n = 55) but many of these focused on low income and minority populations. The diversity of included studies limited meta-analysis to outcomes for four study groups. These analyses found evidence of moderate quality of the effectiveness of LHWs in promoting immunisation childhood uptake (RR 1.22, 95% CI 1.10 to 1.37; P = 0.0004); promoting initiation of breastfeeding (RR = 1.36, 95% CI 1.14 to 1.61; P < 0.00001), any breastfeeding (RR 1.24, 95% CI 1.10 to 1.39; P = 0.0004), and exclusive breastfeeding (RR 2.78, 95% CI 1.74 to 4.44; P <0.0001); and improving pulmonary TB cure rates (RR 1.22 (95% CI 1.13 to 1.31) P <0.0001), when compared to usual care. There was moderate quality evidence that LHW support had little or no effect on TB preventive treatment completion (RR 1.00, 95% CI 0.92 to 1.09; P = 0.99). There was also low quality evidence that LHWs may reduce child morbidity (RR 0.86, 95% CI 0.75 to 0.99; P = 0.03) and child (RR 0.75, 95% CI 0.55 to 1.03; P = 0.07) and neonatal (RR 0.76, 95% CI 0.57 to 1.02; P = 0.07) mortality, and increase the likelihood of seeking care for childhood illness (RR 1.33, 95% CI 0.86 to 2.05; P = 0.20). For other health issues, the evidence is insufficient to draw conclusions regarding effectiveness, or to enable the identification of specific LHW training or intervention strategies likely to be most effective.

Authors' conclusions
LHWs provide promising benefits in promoting immunisation uptake and breastfeeding, improving TB treatment outcomes, and reducing child morbidity and mortality when compared to usual care. For other health issues, evidence is insufficient to draw conclusions about the effects of LHWs.

/pdf/lay-health-workers-in-primary-and-community-health-care-for-561d75zkrw.pdf

Lay health workers in primary and community health care for maternal and child health and the management of infectious diseases.

Potentially malignant disorders of the oral and oropharyngeal mucosa; terminology, classification and present concepts of management

Incidence rates of oral cancer and natural history of oral precancerous lesions in a 10-year follow-up study of Indian villagers.

Sixty-six patients with oral submucous fibrosis were followed-up for a period of 17 yr (median observation 10 yr) in Ernakulam District, Kerala, India. Oral cancer developed in five (7.6%) patients. The malignant transformation rate in the same sample was 4.5% over a 15-yr observation period (median 8 yr). These findings impart a high degree of malignant potential to this condition.

Malignant transformation rate in oral submucous fibrosis over a 17-year period.

Oral submucous fibrosis (OSF) is a high risk precancerous condition, predominantly affecting Indians. Consumption of chilli was hypothesized as an etiologic factor on the basis of ecological observations and a solitary animal experimental study. Subsequent epidemiologic studies that included case-series reports, large cross-sectional surveys, case-control studies, cohort and intervention studies have identified areca nut as the major etiologic agent. Tissue-culture studies involving human fibroblasts, areca nut extracts and areca nut alkaloids supported this etiologic hypothesis by showing fibroblastic proliferation and increased collagen formation. Currently, the role of genetic susceptibility and that of autoimmunity are receiving attention. The influence of nutritional factors, if any, remains unclear.

Etiology of oral submucous fibrosis with special reference to the role of areca nut chewing

A case-control study to elucidate the etiology of oral submucous fibrosis was conducted in Bhavnagar, Gujarat. Sixty consecutively arriving oral submucous fibrosis patients at a dental clinic were selected as cases. An equal number of controls matched for age, sex, religion and socioeconomic status were selected from individuals who did not exhibit any oral mucosal lesion or condition. Among cases, 98% chewed areca nut regularly in one form or the other whereas among controls 35% chewed areca nut, giving an overall relative risk of 109.6. Areca nut chewing was practiced most commonly in the form of mawa: a mixture containing mainly areca nut (over 90% by weight), some tobacco, and a few drops of lime. Mawa chewers and those who chewed mawa along with other chewing habits showed very high relative risks. The relative risks increased with increase in the frequency as well as the duration of chewing habits. In a bivariate analysis the effect of frequency and duration of chewing appeared to be multiplicative. The present findings confirm areca nut as the most important etiologic factor in oral submucous fibrosis.

A case-control study of oral submucous fibrosis with special reference to the etiologic role of areca nut.

Results of an epidemiologic house-to-house survey of oral cancer and leukoplakia among 50915 adult villagers in 4 states of India which were selected according to various types of chewing and smoking habits are presented. 26 oral cancer cases were found in the survey. There was a predominance of men. Leukoplakias were already observed in the 15-24 year old age group and a considerable number were in the 25-34-year age group. Intra-oral locations of the leukoplakias were found to vary within the 4 states depending on the chewing and smoking habits prevailing. The leukoplakias were analyzed with regard to intra-oral locations and correlation with habits. Special habits such as hookli smoking and reverse smoking were associated with leukoplakias on the labial mucosa and on the palate respectively. The histologic analysis of biopsies from 723 leukoplakias showed variations in the type of hyperkeratosis which may depend on habits. The prevalence of epithelial atypia ranged from 3-12.4% in the 4 states. Epithelial atypia was seen in 8.4% of homogeneous leukoplakias but in 59.1% of speckled leukoplakias.(BJB (AU. MOD.))

D. K. Daftary

Papers

Incidence rates of oral cancer and natural history of oral precancerous lesions in a 10-year follow-up study of Indian villagers.

Malignant transformation rate in oral submucous fibrosis over a 17-year period.

Etiology of oral submucous fibrosis with special reference to the role of areca nut chewing

A case-control study of oral submucous fibrosis with special reference to the etiologic role of areca nut.

Epidemiologic and histologic study of oral cancer and leukoplakia among 50,915 villagers in India.