J. J. Pindborg

Histological typing of cancer and precancer of the oral mucosa

Histological Classification of Cancer and Precancer of the Oral Mucosa.- Definitions and Explanatory Notes.- Carcinomas.- Benign Lesions Capable of Microscopically Resembling Oral Squamous Cell Carcinoma and Oral Verrucous Carcinoma.- Precancerous Lesions (Clinical Classification).- Precancerous Lesions (Histological Classification).- Benign Lesions Capable of Resembling Oral Precancerous Lesions.- Precancerous Conditions.- TNM Classification of Lip and Oral Cavity Carcinomas.- Illustrations.

Oral submucous fibrosis

Abstract On the basis of the literature and personal experience, we have discussed a pcculiar oral disease—submucous fibrosis—seen mainly among East Indians. The condition is chronic and is clinically characterized by blanching and stiffness of the oral mucosa. Histologically, the oral connective tissue becomes hyalinized and the overlying epithelium markedly atrophic. The disease may be due to an irritant (chili?), acting over a long period of time. Evidence is presented that submucous fibrosis may be considered an important precancerous condition in Southeast Asia.

THE CALCIFYING ODONTOGENIC CYST: A POSSIBLE ANALOGUE OF THE CUTANEOUS CALCIFYING EPITHELIOMA OF MALHERBE

Abstract The existence of a new odontogenic lesion—the calcifying odontogenic cyst—is documented by fifteen examples and its histogenesis is described. There appears to be no predilection for sex, age, or location. In only one case has there been a recurrence. The similarity of this cyst to the cutaneous calcifying epithelioma of Malherbe and other lesions is discussed.

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

The paper presents the results of an epidemiologic house‐to‐house survey of oral cancer and lcukoplakia among 50,915 adult villagers in 4 states of India which were selected according to various types of chewing and smoking habits. Twenty‐six oral cancer cases were found in the survey. The prevalence of leukoplakia ranged from 0.2 to 4.9%. There was a predominance of men. Leukoplakias were already observed in the 15‐ to 24‐year age group, and a considerable number were in the 25‐ to 34‐year age group. Intra‐oral locations of the leukoplakias were found to vary within the 4 states depending upon the chewing and smoking habits prevailing. The leukoplakias were analyzed with regard to intra‐oral locatios and correlation with habits. Special habits like hookli smoking and reverse smoking are 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 upon habits. The prevalence of epithelial atypia ranged from 3.0% to 12.4% in the 4 states. Epithelial atypia was seen in 8.4% of homogeneous leukoplakias but in 59.1% of speckled leukoplakias.

An epidemiologic assessment of cancer risk in oral precancerous lesions in India with special reference to nodular leukoplakia.

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.

Oral Submucous Fibrosis as a Precancerous Condition

An evaluation of the malignant potential of submucous fibrosis, based on observations of 89 patients with the disease in Ernakulam District, Kerala, India was done. Out of the 89 patients, 12 were referred patients and 77 were diagnosed in population based studies. At the time of first examination oral cancer was found to be coexistent in nine (10%) cases. For 66 patients follow-up observations ranging from 4 to 15 yr (median 8 yr) were available. During this period malignant transformation was observed in three patients (4.5%). Considering malignant transformation and coexistence together, oral cancer was observed in 13% of the present material. Leukoplakia was found in 26% of the patients with submucous fibrosis. Out of 42 submucous fibrosis patients biopsied, 12% showed squamous cell carcinoma, 26% epithelial dysplasia, and 76% atrophic epithelium. These findings reinforced the hypothesis that submucous fibrosis is a precancerous condition.

AIDS and the oral cavity. Epidemiology and clinical oral manifestations of human immune deficiency virus infection: a review.

Since the first patients with acquired immune deficiency syndrome (AIDS) were seen in 1981, the disease has been recognized as an epidemic, now considered a major health threat. This article reviews, on the basis of the literature and personal observations of 120 human immune deficiency virus (HIV) infected patients, some aspects of the HIV (HTLV III/LAV) infection with emphasis on epidemiology and clinical aspects. The clinical oral manifestations include 5 groups of lesions: fungal infections, bacterial infections, viral infections, neoplasms and lesions of unknown etiology. In total, these 5 groups comprise 34 different lesions of the oral cavity.

A follow-up study of sixty-one oral dysplastic precancerous lesions in Indian villagers☆

In a 7-year follow-up study of 107 cases of oral epithelial dysplastic precancerous lesions in Indian villagers, 6.6 per cent were found to develop into carcinomas. A clinical spontaneous regression occurred in 14.8 per cent. Follow-up biopsies showed histologic regression of dysplasia in six cases.

Classification of oral lesions associated with HIV infection

This article proposes a classification for oral lesions associated with HIV infection. The lesions can be classified into those with fungal, bacterial, or viral origin whereas other subgroups include neoplasms, neurologic disturbances, and lesions of unknown cause. This proposal is neither final nor exhaustive and is forwarded as a basis for epidemiologic surveys.

Yeast species and biotypes associated with oral leukoplakia and lichen planus.

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: Candida 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.(ABSTRACT TRUNCATED AT 250 WORDS)