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One hundred and twenty Danish homosexual men were enrolled to characterize risk factors for anal type-specific human papillomavirus (HPV) expression and to examine its association with anal epithelial atypia. Detection of HPV strongly correlated with immunosuppression measured by T-lymphocyte subset markers and rose nearly linearly from 7.3% among subjects with CD4/CD8 ratios above 1.0 to 35.3% among those with a ratio below 0.4 (p trend = 0.003). No association was found between presence of HPV and a wide range of lifestyle factors including number of sex partners/year, smoking, alcohol consumption and illegal drug intake. However, self-reported history of anal condyloma in the past year was correlated with HPV (p less than 0.001). Simultaneous testing for presence of HPV in the oral cavity showed evidence of HPV 16,18 and 31,33,35. Anal smears were abnormal in 19.5% of the men and correlated strongly with presence of HPV (OR = 6.1, p less than 0.001). Type-specific associations were found with HPV 31/33/35 (OR = 8.5) and HPV 16/18 (OR = 3.1) only. The association remained significant after adjusting for immune status. Overall, HPV was detected in 50% of the cases with abnormal smears. However, HPV was found in all subjects with abnormal smears and a CD4/CD8 ratio below 0.4, compared to only 3 of 14 subjects with abnormal smears and a ratio greater than or equal to 1.3. In conclusion, (1) HPV may be missed in a substantial number of infected subjects with a normal immune system. This may have an impact on studies trying to describe risk factors for HPV transmission and its correlation with cancer development. (2) The finding of HPV 16,18 and 31,33,35 in the oral cavity makes oral-genital sexual activity at least a hypothetical route of transmission for these HPV types. (3) HPV appears to play a central role in the development of anal epithelial abnormality.

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.

One hundred Danes with oral cancer who were collected consecutively from 1986 to 1991 were evaluated retrospectively. The study included subjective and objective observations in 56% men and in 44% women. M:F ratio was 1.2:1. Fifty percent of the patients were non-smokers. Nine percent were women who did not drink alcohol. Ten percent of the patients were between 40 and 49 years of age, 20% between 50 and 59 years, 35% were between 60 and 69 years and 20% between 70 and 79 years of age. This may reflect a tradition of early drinking and smoking. Doctor's delay was the cause of delayed referral in 14% of the cases while 72% of the patients were the cause themselves for the delayed referral.

A total of 84 HIV-infected homosexual men having either normal oral mucosa (NOM), erythematous candidiasis (EC) or pseudomembranous candidiasis (PsC) were included in the study. The patients were evaluated by median number of peripheral CD4+ cells, CD8+ cells and by lymphocyte function assessed by poke-weed mitogen test. There was a significant difference between CD4+ counts among patients with the two subtypes of candidiasis (95% CI of median difference: 10-240/mm3; P = 0.03), but not for pokeweed mitogen response. Survival analysis showed that after 2 y there was no significant difference in development of AIDS between patients with EC and PsC (P = 0.29). If patients with both types of oral candidiasis were pooled and compared with patients with NOM, a significant difference in development of AIDS was found (P = 0.04). It is concluded that HIV-infected patients with oral candidiasis of any subtype (EC or PsC) are significantly more immune suppressed and show a faster development of AIDS than HIV-infected patients with NOM. However, in this cohort, EC and PsC are of equal importance as predictors for immune suppression and AIDS development.

The calcifying epithelial odontogenic tumor (CEOT) was described as an entity by Pindborg in 1955. In 1976 a review of the world literature comprising 113 cases was published. Since then, several studies concerned with pathological aspects of this tumor have appeared. Many of these studies have focused on the nature of the amyloid-like material present in CEOT. In this paper a new case is presented and the literature after 1976 is reviewed with respect to histopathological aspects of CEOT.

Incidence of oral submucous fibrosis was calculated from a 10-yr prospective intervention study of 12,212 individuals with a strong component of health education on tobacco and area nut chewing. Based on 11 new cases among 6341 chewers, the annual incidence was 8.0 per 100,000 among men and 29.0 for women. An earlier 10-yr follow-up study, with no intervention component, served as control. Based on 11 new cases among 3,809 chewers, the annual incidence was 21.3 per 100,000 for men and 45.7 for women controls. Although the decrease in the incidence in the intervention cohort was not statistically significant due to small number of cases, the results underscored the causal role of areca nut chewing and indicated the potential for primary prevention of oral submucous fibrosis.

A group of 20,358 villagers in two districts of India has been followed for 7 years to study the incidence of oral leucoplakia. The follow-up rate of the population in two districts ranged from 61% to 71%. In one of the districts (Bhavnagar) no new cases of leucoplakia were found among females in the 7-year period. Among males 105 cases developed (4-0/1000/year). The incidence was highest among hookli (clay pipe) smokers. In the Ernakulam district the incidence among males was 3-3/1000/year whereas among females it was 1-9/1000/year. The mixed habits group had the highest incidence of oral leucoplakias (7-2 and 9-9/1000/year among males and females respectively).

The course of reticular, papular, bullous, plaque-type, atrophic and ulcerative lesions of oral lichen planus (OLP) was studied in 611 patients. Mean age of the patients was 53 years and two-thirds were women. The patients were followed for periods from 1 to 26 years (mean, 7.5 years). The various clinical types had somewhat different courses. Papular affections were seen mainly in the initial phase and had a transitory course. Ulcerative lesions, although more persistent, also generally showed a short-term course. The atrophic form was fluctuating with many remissions and new-established affections. The plaque-type was a more constant form, but also demonstrated many newly established affections. After a few years, many patients had persistent lesions that no longer included the affections most characteristic of OLP, i.e. the reticular and the papular form. Initial presence of papular affections was associated with ages below 50 and atrophic lesions with ages above 60. Plaque-type affections were seen with a significantly higher frequency among tobacco smokers at the onset of OLP. No other correlation was found between the initial presence, the remission and the development of the different clinical forms and various factors as age, sex, general diseases, medication and tobacco smoking. Treatment with topical steroid and/or antimycotics had no effect on the long-term course of the various clinical forms, and it had no persistent effect on symptoms related to OLP. Complete remission was seen in 17% of the patients, and it showed a reverse association with the initial presence of plaque-type affections. However, complete remission was associated with an initial presence of papular affections. No other predictive factor of total remission was found.

In the eastern part of Java and on the island of Bali betel chewing is a very common habit confined principally to females. The purpose of the present study was to examine the influence of betel chewing on the prevalence of dental caries. The study, which is based upon 982 villagers, indicates a strong inverse relationship between the prevalence of dental caries and the intensity of betel chewing. The possible mechanisms whereby betel chewing may have a caries-inhibiting effect are discussed.

– The occurrence in oral submucous fibrosis of small raised blue spots has not been reported. This feature was observed in nine (22%) of 40 submucous fibrosis cases diagnosed in the Ernakulam district, Kerala, India. None of the patients complained of bleeding from the spots or from elsewhere, nor was there any history of systemic disorders. Histologically, the lesions could be explained by juxtaepithelial, endorthelial-lined luminae containing erythrocytes and the presence of juxta- and intraepithclial petechial homorrhages.

During an epidemiologic study of oral cancer and precancerous lesions among Indian villagers, a lichen planus-like lesion was observed in Kerala. The lesion consisted of white, wavy, parallel, non-elevated lines that could not be scraped off. The lesion occurred exclusively among chewers and at the site of placement of quid. There were no subjective symptoms. The peak prevalence of the 35 diagnosed lesions was in the 35-44 years age-group for males and 45-54 for females. There was a marked female predominance. The histologic features were very similar to those seen in oral lichen planus.

The histopathologic criteria set down by Lever for skin lesions of discoid lupus erythematosus (DLE) and the criteria for oral DLE suggested by the World Health Organization (WHO) have been tested on 136 biopsy specimens from oral lesions comprising 42 cases of clinically typical DLE, 24 cases of atypical DLE, 25 cases of lichen planus (LP), 25 cases of leukoplakia, 13 cases of indefinite diagnosis termed DLE? LP? and seven electrogalvanically- induced white lesions. Following studies of inter- and intraexaminer variation, the final recording was done in random order without the investigators knowing the clinical diagnosis in each case. The results showed that Lever's criteria had a high specificity for oral DLE as compared to LP and leukoplakia, but the sensitivity for clinically atypical oral DLE was rather low. The criteria established by the WHO showed no specificity for oral DLE as compared to LP. Neither the criteria by Lever nor the criteria of the WHO were specific for oral DLE as compared to electrogalvanically induced white lesions. Both sets contained criteria showing rather high inter- and intraexaminer variation. Therefore, there is a need to establish a set of histopathologic criteria showing high sensitivity and specificity for both clinically typical and atypical DLE, based on criteria showing a low inter- and intraexaminer variation.

The occurrence of central papillary atrophy of the tongue among tobacco users, its clinical characteristics and the long term behavior in relation to changes in tobacco use was studied in 182 individuals in Ernakulam district, Kerala, India. Almost all (98%) lesions occurred among bidi smokers. Clinically, about 31% occurred in combination with bidi smoking associated lesions such as palatal erythema (14%), leukoplakia (8%) or both (3%). Histologic evaluation in 12 biopsies using single PAS stained sections showed candidal hyphae in 67%. A 10-yr follow-up (mean: 6.7 yr) of the 182 lesions showed that the regression was highest (87%) among those who stopped their smoking habit and persistence among those who did not reduce or stop their smoking habits. The findings from this study confirm a strong link between bidi smoking and central papillary atrophy of the tongue in rural Indian populations.

The malignant potential of oral lichen planus was assessed on the basis of observations in 722 patients found among 27,599 individuals examined in various epidemiologic studies in Kerala, Ernakulam district, India. Seven hundred and two patients with oral lichen planus were re-examined annually over a 10-year period with a mean observation period of 5.1 years. Most of the lesions (93%) were observed among tobacco users. Carcinoma developed in 3 (0.4%) patients with oral lichen planus. Clinically, all 3 had atrophic components in their lesions, and all were tobacco users. The relative risk of a lichen planus developing oral cancer compared to a tobacco user was estimated as 3.3. However, this relative risk was not significant. Histologically, 74% of the 94 biopsies from oral lichen planus showed epithelial atrophy. Two of the 3 in whom cancer developed also showed epithelial atrophy. It is felt that epithelial atrophy probably renders the mucosa more vulnerable to the carcinogenic action of tobacco. Although this study could not confirm the precancerous nature of this disease with a high degree of certainty, the disease did not appear to be innocuous either.

In an extensive epidemiologic house-to-house survey, undertaken to study oral cancer and precancerous conditions, 101,761 villagers were examined in the Poona district in the Maharashtra state in India. Besides detection of 12 oral cancers, prevalences were established for leukoplakia (0.67%), preleukoplakia (0.86%), and submucous fibrosis (0.03%). The sample was also studied for chewing and smoking habits, which were practised by 54.4% of the individuals. Among males the most common habit was chewing tobacco with lime, whereas the dominating habit among females was the use of mishri (burned tobacco). The strongest association found was between bidi smoking and mixed habits and leukoplakia. Only a few cases of leukoplakia were found among mishri users. Except for submucous fibrosis it was found that prevalence does not depend on sex if tobacco habits are taken into account. Une etude epidemiologique du cancer buccal et de l'etat precancŕeux chez 101 761 villageois du Maharashtra (Inde) Dans le cadre d'une vaste enquěte epidemiologique de porte en porte, entreprise dans le but d'etudier le cancer buccal et l'etat precancereux, 101 761 villageois on ete examines dans le district de Poona de l'Etat du Maharashtra (Inde). L'etude a permis de depister 12 cancers buccaux, mais aussi d'etablir des prevalences pour la leucoplasie (0.67%), la preleucoplasie (0.86%) et la fibrose sous-muqueuse (0.03%). On a egalement observe les habitudes de ces villageois en ce qui concerne l'usage du tabac et la mastication de certaines substances, qui sont pratiques par 54.4% d'entre eux. L'habitude la plus repandue chez les hommes consiste a mǎcher du tabac et de la chaux, alors que les femmes preferent le mishri (tabac brǔle). L'association que l'on a constatee le plus souvent est celle de l'usage du bidi ou d'habitudes combinees et de la leucoplasie. Quelques cas de leucoplasie ont ete observes chez les amateurs de mishri. La fibrose sous-muqueuse mise a part et compte tenu de l'usage du tabac, on constate que la prevalence ne depend pas du sexe.

In a sample of 450 patients with oral leukoplakias, 32 used snuff, which was a Danish wet variety, Goteborg snus ® (Gothenburg Snuff). The group of snuff users consisted of males only, with a mean age of 58.4 years. The mean life exposure time lo snuff was 197,000 hours, the equivalent of 22 years of constant use. Patients with leukoplakia due lo the use of snuff experienced fewer symptoms than did patients with leukoplakia due to other unknown causes. The snuff users also tended to be older at first examination, and to have a higher alcohol intake. Histological changes characteristic of snuff-users' leukoplakias were: (1) vacuolated cells in the upper part of the spinous cell layers of the epithelium with intervening streaks of parakeratinized cells, (2) epithelial hyperplasia, and (3) hyalinized, eosinophilic deposits around salivary glands. However, statistically significant differences were not found between snuff-induced leukoplakias and other leukoplakias either as lo dysplasia observed histologically or as to malignant development.

In the district of Srikakulam in Andhra Pradesh in South India the habit of reverse smoking is widespread. In a house to house survey of oral cancer and precancerous conditions, comprising 10,169 villagers, 43·8% were reverse smokers; the female: male ratio being 1·7: 1. Ten previously undiagnosed cases of oral cancer, 9 located to palate, were found. The prevalences for leukoplakia, preleukoplakia and leukokeratosis nicotina palati were 4·9%, 2·9% and 9·5%. Of 497 leukoplakias, 422 were located to the palate and 413 of these patients had the habit of reverse smoking. Histologically, 80% of 381 palatal biopsies had a hyperorthokeratosis. Epithelial atypia was found in 15·3% of leukoplakias, in 3·6% of the preleukoplakias, and in 9·1% of leukokeratosis nicotina palati. Various explanations for the habit of reverse smoking are suggested and discussed. In addition to reverse smoking, other tobacco habits were also recorded; all habits and oral lesions were compared and have been discussed according to their apparent interrelationships and distribution by sex and age. ImagesFigs. 3-4Figs. 5-6Figs. 7-8Figs. 11-12Fig. 2Figs. 9-10

No abstract available

Two male patients with oral leukoplakias exhibiting a peculiar type of apparent dysplastic changes have been followed for 4 and 6 years, and a series of biopsies have been examined by light and electron microscopy. The apparent lack of normal epithelial stratification below the keratinized cell layers was mainly caused by the frequent appearance of large ballooned cells and multinuclear giant cells. The centre of the large ballooned cells contained aggregations of chromatin and evenly-dispersed microtubulus surrounded by a thick rim of tonofibril bundles. In the peripheral cytoplasm large numbers of smooth-surfaced endoplasmic reticulum were found, but no Golgi apparatus was observed. In addition, several autophagocytic bodies were recorded. Along the cell membrane only a few desmosomes were present, whereas aggregations of digested desmosomes were found in the cytoplasm. On the basis of the ultrastructural findings, it is suggested that the large ballooned cells represented epithelial cells arrested in early stages of mitotic division. The epithelial cells in interphase exhibited a normal ultrastructure except for large nucleoli with varying degrees of condensation of nucleolonema and vacuolization. Further, atypical dense granular aggregations and strands of fine fibrillar material were recorded in the nuclei. It is suggested that this new type of oral leukoplakia has a viral etiology.

Regional variations in the characteristics of submucous fibrosis were studied in two districts in India. In Pune district this condition involved soft palate, uvula and retromolar areas significantly more often than in Ernakulam district. The tongue, floor of the mouth and the hard palate were not involved in Pune. The age of the patients in Pune district was lower than in Ernakulam district. Associated oral cancer, leukoplakia and petechiae were observed solely among patients in Ernakulam. The most important etiologic factor for submucous fibrosis is the chewing of areca nut, and in both areas studied all patients chewed areca nut. In Pune, cured areca nut without other ingredients was chewed by 66% and in Ernakulam, raw areca nut was chewed as an ingredient of pan with tobacco by 100%. Thus in Ernakulam, the juice and the quid were mostly spat out, whereas in Pune they were swallowed. The regional variations in the characteristics of submucous fibrosis could be related to the differences in the areca nut chewing habit between the two areas.

A review of the world literature has revealed 113 cases of the calcifying epithelial odontogenic tumor. The clinical, radiographic, and histopathologic features are analyzed. Various treatments that have been carried out are related to the frequency of recurrence. The theories of histogenesis are discussed and an attempt is made to explain the nature and origin of the amyloid-like substance.

Verrucous hyperplasia of the oral mucosa is a relatively unrecognized entity that may resemble verrucous carcinoma clinically and histologically. This study describes the clinical and histological features of the condition, particularly in relation to verrucous carcinoma. Sixty-eight cases were selected by screening all lesions accessioned as verrucous or papillary lesions of various kinds, dysplasias and leukoplakias. More cases occurred in women (56%) than in men (44%). All but 3 patients were 50 yr. or older, and 35% were over 70. Gingiva or alveolar mucosa were involved most frequently (27%), followed by cheek (24%), tongue (17%), floor of mouth and lip (12% each), and palate (8%). Verrucous processes are either sharp and heavily keratinized or blunt with a thin parakeratin layer. In 36 patients (53%), there was associated leukoplakia; in 20 (29%), there was associated verrucous carcinoma; in 45 (66%), associated epithelial dysplasia; and in 7, (10%) there was associated squamous carcinoma. Verrucous carcinoma or squamous carcinoma. Verrucous hyperplasia is best distinguished from verrucous carcinoma in biopsies taken at the margins of the lesions. In the former, the verrucous processes and the greater part of the hyperplastic epithelium are superficial to adjacent normal epithelium. In the latter, the verrucous processes are superficial, but the broad rete processes extend considerably deeper than adjacent normal epithelium, often pulling a margin of normal epithelium down with them into the underlying connective tissue.

The lateral periodontal cyst is of developmental odontogenic origin and must be differentiated from the gingival cyst of adults, a primordial cyst in a lateral periodontal position, and a cyst of inflammatory origin. This paper is based on a histologic study of five cases. Four were in the mandibular premolar region and one in the lateral incisor-canine region of the maxilla. The cysts are lined by a thin non-keratinized epithelium which resembles the reduced enamel epithelium. Many of them arecharacterized by the presence of localized plaque-like thickenings of their epithelial linings, consisting of fusiform or large swollen, edematous cells. These epithelial thickenings appear to result from a localized proiferation of basal cells. The lateral periodontal cyst may arise initially as a dentigerous cyst which develops by expansion of the follicle along the lateral surface of the crown and comes to lie on the lateral aspect of the root if tooth eruption is normal. Alternatively, it may arise from the cell rests of Malassez.

In a cohort of 740 referred patients with oral lichen planus eight patients were found with a sharply demarcated slightly depressed erythroplakic area. The histological examination of the biopsies from the erythroplakic lesion of the 8 patients showed seven with epithelial dysplasia. In addition, two of the lesions revealed a squamous cell carcinoma. In the erythroplakic lesion without dysplasia the histological picture was found to be characteristic of lichen planus. All eight patients were seen at later follow-up examinations (median observation period: 3.6 years) and in one patient a squamous cell carcinoma arose in the erythroplakic lesion during the control period. It is concluded that the reported erythroplakic lesions in relation to oral lichen planus seem to be premalignant and they should be followed and/or treated like oral erythroplakias.

In a house-to-house survey in South India, comprising 10,000 villagers, the age-adjusted incidence rate per 1,000 person-years for oral lichen planus was found to be 2.1 for males and 2.5 for females, based upon a 10-year follow-up study. The highest incidence was in the age group 55-64 for males and 45-54 for females. The age-adjusted relative risk was higher for the 'chewing habits' group (6.2) than for the 'smoking habit' group (2.2). The combined effect of the two habits appeared to be multiplicative; the age-adjusted relative risk for the mixed habit group being 13.7.

A house-to-house survey of 11 villages selected by random sampling was carried out in Bilugyun. Chaung-zone township. Mon State of South Eastern Burma to study the prevalence of oral precancerous lesions and smoking and chewing. A total of 6000 villagers who were above 15 years at the time of this study were examined. The prevalence of preleukoplakia was 0.3%, leukoplakia 1.7%, lichen planus 0.4%, leukokeratosis nicotina palati 2.3, erythroplakia 0.1%, submucous fibrosis 0.1%, and cancer 0.03%. A correlation was done between habits and lesions.

Chronic oral candidiasis is generally not considered a premalignant condition. We report on two patients with carcinoma in situ and carcinoma in the soft palate, probably preceded by long lasting chronic Candida infection. The first patient was a 56-year-old woman who suffered from disturbances in the calcium and potassium metabolism and high blood pressure due to a previous goiter operation during which the parathyroids had been removed. She also suffered from bronchitis and had been smoking 12 cigarettes a day for many decades. For several years she had had more or less constant symptoms from airway infections. Increasing symptoms from the throat had developed 2 years before referral and, in this period, she had been in constant antifungal therapy with no effect on the symptoms. Objectively, the entire soft palate, uvula and the palatoglossal arches were fiery red with whitish plaques which were not removable (Fig. 1). A biopsy revealed severe dysplasia and focal carcinoma in situ Subsequently, the lesion in the soft palate was partly removed by laser surgery followed by radiation therapy over a period of 2 month. One year later there was no signs of recurrence (Fig. 4). The second patient, a 53-year-old healthy woman, was referred because of difficulties in eating due to pain in the throat which had existed for 2 years. Without any effect on the symptoms, she had had antifungal therapy for 4 weeks. The patient had been smoking 15 cigarettes a day for many years. Objectively, an area with whitish plaques and nodules on an erythematous background was found (Fig. 5).(ABSTRACT TRUNCATED AT 250 WORDS)

In Central Java and on the island of Bali 779 and 437 villagers respectively were examined for dental mutilations. In Java 81.1 % of the males and 99.2 % of the females showed dental mutilations in the form of grinding the incisal and vestibular surfaces of the maxillary incisors and canines. In Bali, the figure for males was 91.3 % and for females 96.6 %. In Java as well as on the island of Bali most of the mutilations had been subjected to artificial staining. The authors have found a relief in the temple of Borobudur, built about 800 A. D., possibly depicting the performance of a dental mutilation.

Tissue from 40 oral premalignant lesions were investigated for the presence of blood group antigens A and B. The material included 18 leukoplakias, 1 erythroplakia, and 3 lichen planus, all with varying degrees of epithelial dysplasia, and 18 leukoplakias without histological evidence of impending malignancy. Thirty-eight benign keratotic oral mucosal lesions were included as a control group. The antigens were demonstrated by a double layer immunofluorescence technique, and the reactivity was compared, by titration, to the reactivity of adjacent normal epithelium from the same patient. All 22 lesions with dysplasia showed decreased reactivity for blood group antigen. Among the 18 leukoplakias without any signs of impending malignancy 4 cases demonstrated loss of antigen reactivity. None of 38 benign control lesions showed any change in antigen reactivity as compared to normal adjacent epithelium.

Of 36 patients, 17 had oral leukoplakia, including homogeneous and nonhomogeneous types, and 19 had reticular lesions of oral lichen planus. A sample of yeast flora in each patient was taken from the pathologic lesion as well as from normal-appearing mucosa. The isolated yeasts were identified according to species level, and identification was extended beyond the species level for one species, Candida albicans , to reveal the biotype by means of the Odds and Abbott procedure comprising tests for acid and salt tolerance, proteinase production, resistance to 5-fluorocytosine and safranine, and assimilation of urea, sorbose, and citrate. Yeasts were present in the lesions of 82% of leukoplakia patients, compared to 37% of lichen planus patients, a frequency of yeasts corresponding to that in healthy adults. C. albicans was the dominating species in lesions of both diseases, constituting 82% of all yeasts in the leukoplakia lesions. In addition, the following species were identified: Canadia tropicalis, Candida pintolopesii, Torulopsis glabrata , and Saccharomyces cerevisiae . Eighteen biotypes of C. albicans were encountered, the most frequently occurring biotypes being 355 and 177. Differences between C. albicans biotypes isolated from pathologic and normal mucosa were encountered in five of eleven leukoplakia patients and in one of three lichen planus patients. This indicates that the oral cavity comprises several ecologic niches for yeasts. As nonhomogeneous leukoplakias are more likely to develop into carcinoma than are homogeneous leukoplakias, it is interesting to note that the C. albicans biotypes isolated from nodular lesions (one type of nonhomogeneous leukoplakia)—biotypes 145, 175, and 575—rarely occur. The observation might indicate a possible causal role of some C. albicans biotypes in transformation of leukoplakia into carcinoma.

One hundred patients (43 women and 57 men) with intraoral squamous cell carcinoma were questioned about their tobacco and drinking habits and then subjected to a thorough intraoral clinical examination. Twelve of the women did not use tobacco and did not have increased alcohol consumption. Only three of the men did not use tobacco, and 70% had daily consumption of alcohol. Where location of the carcinoma was concerned, the men had two and a half times as many carcinomas of the floor of mouth and inferior surface of tongue as the women. An astonishing finding was that 15% of the patients did not have subjective symptoms even if the tumour was more than 4 cm in diameter. On the basis of information obtained from the patients, 31% had been referred after a considerable delay. It is suggested that more information is required among physicians and dentists concerning the early diagnosis of intraoral malignancies.

Oral cancer presents a serious public health problem in south-east Asian countries. In Sri Lanka and India 35-40% of all cancers are reported to be oral cancers, which are curable if detected in the early stages. The idea that, in developing countries, one of the few practical approaches to early detection of these cases could be through the utilization of primary health care workers was tested in a field study carried out in Sri Lanka. In a control area the subjects with oral lesions were identified by medical/dental officers. In the study, 34 primary health care workers were able, alongside their routine duties, to examine the oral cavity of 28 295 subjects during a period of 52 weeks; 1220 subjects were detected with lesions needing re-examination. The performance of these primary health care workers was very satisfactory in terms of the number of cases detected and the accuracy of their diagnoses, which were verified by re-examination at a specially designated referral centre. The clinical diagnoses of the three categories of lesions detected were as follows: stage 1 lesions for observation (homogeneous or ulcerated leukoplakia), stage 2 lesions for investigation (speckled leukoplakia, erythroplakia, or submucous fibrosis), and stage 3 lesions for treatment (cancer). There was 89% correspondence between the stage 1-3 diagnoses by the health workers and the clinical diagnoses made at the referral centre. However, compliance by patients was low because only 50% of the cases detected in the field attended the referral centre. The cost-effectiveness of this approach to cancer control has been demonstrated.

A study of 112 biopsy specimens from Danish oral leukoplakia patients and 145 biopsy specimens from Indian leukoplakia patients revealed a chevron-like keratinization of the epithelium in a number of cases. Clinically, this type of keratinization was often characterized by a pumice-like appearance. The clinical and histologic changes were only observed in tobacco users, and appeared to be associated particularly with use of pipes, snuff, and hooklis.

In a house-to-house screening survey, 12,212 tobacco chewers and smokers were selected from the rural population in the Ernakulam district, Kerala state, India. These individuals were interviewed for their tobacco habits and examined for the presence of oral cancer and precancerous lesions, first in a baseline survey, and then annually, over a five-year period. They were educated using personal and mass media communication to give up their tobacco habits. The control group was provided from the results of the first five years of a 10-year follow-up study conducted earlier by the authors in the same area with the same methodology but on different individuals without any educational intervention. The stoppage of the tobacco habit was substantially higher in the intervention group (9.4%) compared to the control group (3.2%). A logistic regression analysis showed that the behavioural intervention was helpful to all categories of individuals, however, the effect was different for different categories: intervention was more helpful to men, chewers, and those with a long duration of the habit. These individuals rarely quit their habit without intervention.

A cohort of 12,212 tobacco users was followed up annually to assess malignant potential of oral precancerous lesions in the Ernakulam district in Kerala, India. A total of 19 new oral cancers were diagnosed over a period of 8 years, and 15 (79%) of these arose from some preexisting precancerous lesion or condition. Nodular leukoplakia showed highest rate of malignant transformation (16% per year) as six of 13 nodular leukoplakia underwent malignant transformation over a mean follow-up period of 2.8 years. The relative risk (3243.2) compared with individuals with tobacco habits but without any precancerous oral lesion was also the highest for nodular leukoplakia. In addition, nodular leukoplakia was associated with submucous fibrosis in two patients, which progressed to oral cancer and was the clinical diagnosis for four lesions that turned out to be malignant on histopathologic examination. Nodular appearance was noted in two other precursor lesions as well. Thus, 14 of 19 oral cancers (74%) were either preceded by nodular leukoplakia and with lesions showing a distinct nodular appearance, or had the clinical appearance of nodular leukoplakia.

The present report describes malignant development in oral lichen planus (OLP) among 611 patients (409 F, 202 M) followed for periods from 1-26 years (mean: 7.5). During follow-up, 9 patients (1.5%), 8 women (1.9%) and 1 man (0.5%) developed oral squamous cell carcinomas (SCC) in areas of lichen planus lesions. The age of the patients at diagnosis of carcinoma ranged from 56-79 years (mean: 70.4) and the length of follow-up before malignant development ranged from 4.9-24 years (mean: 10.1). The estimated number expected to develop oral cancer in a sample of the general Danish population of similar size, age distribution and follow-up was 0.18 (0.11 F, 0.07 M) i.e., OLP cases showed a 50-fold increase (F = 70- M = 14-fold). The observed number of cancer cases was significantly higher than the estimated number (p less than 0.00001). Therefore, oral lichen planus fulfils the WHO criterion of a premalignant condition.