The Maxillofacial Center for Diagnostics & Research

This Page: Text and Commentary on Abstracts of Population Studies      

Text of Population Study Abstracts, Etc.

Incidence, time trends and follow-up of oral/pharyngeal carcinoma in situ, 1935-1984. Bouquot JE, Kurland LT, Weiland LH. West Virginia University, Morgantown, WV; Mayo Clinic, Rochester, MN

Presented to the International Association of Oral Pathologists in Toronto, Canada, 1986.
Reference: J Oral Pathol 1986; 15:395.

The dearth of epidemiologic studies relating to carcinoma in situ (CIS) of the mouth and pharynx has lead to the acceptance of clinicopathologic data for the descriptive characterization of this disease. Such data, however, cannot be said to represent any population beyond that of the particular hospital from which a study originated. Hence, our understanding of this disease is necessarily skewed to the more difficult or unusual cases. The present investigation is the first to offer a clinical characterization of CIS from a pool of patients known to represent virtually all cases of CIS and invasive carcinoma in a stable population (Rochester, Minnesota, 1935-84). The annual incidence of CIS in this population was 2.0/100,000 (3.7 for males; 0.7 for females), compared to a rate of 12.6 invasive carcinomas/100,000 (20.7 for males and 6.8 for females). Incidence of CIS increased with increasing age, to a maximum of 28.3/100,000 for males 75 years of age and older. Time trends of CIS incidence showed no significant change over 50 years. Clinical features and follow-up results will be reported.
                               This study was supported in part by NIH grand AM30582.

Leukoplakia and carcinoma in situ synchronously associated with invasive oral and oropharyngeal carcinomas in Rochester, Minnesota.

Presented to the American Academy of Oral Pathology, May, 1986.

Gender-specific lip lesion occurrence. Bouquot JE, Gundlach KKH, West Virginia University, Morgantown, WV; University of Hamburg, Hamburg, West Germany.

Reference: Dent Abst 1987; 32:423.

The prevalence of common lip lesions in a Minnesota population of 23,616 white adults older than 35 years of age is reported. Lips were the site of approximately 18.5% of oral mucosal and connective tissue lesions, a point prevalence of 29.6 lip lesions per 1,000 persons examined. Leukoplakia was the most frequent diagnosis (14.5 per 1,000 persons overall; 21.8 per 1,000 males). Labial carcinomas presenting as leukoplakias with or without ulceration occurred in 0.8 per 1,000 persons overall (2.1 per 1,000 males).

The population was biased for age (91% aged 40-70 years), gender (64.1% females), and race (99.5% Caucasians). Gender-specific prevalence rates for 698 labial lesions ranked by frequency of diagnosis are shown in the Table.

The most frequent clinical presentation (46.1% of lesions) was a nonelevated surface change, followed by exophytic masses (33.3%) and vesicles or ulcerations (13.9%). Keratoses accounted for 34.7% of lip lesions and were the most frequent of surface alterations. Hemangiomas were the most frequent of the exophytic lesions.

Approximately 95% of lip leukoplakias were specifically located on the vermillion border, usually of the lower lip (95%). Microscopically confirmed early invasive squamous cell carcinomas (no. = 18) and severe epithelial dysplasias (no. = 12) accounted for 13.7% of lip leukoplakias. All were vermillion lesions in males. Papilloma was the only benign neoplasm diagnosed in this population.

Hemangiomas were almost twice as prevalent in males. Irritation fibromas were the most frequently diagnosed nonvascular masses of the lips, usually occurring in males and on the mucosal surface rather than on the vermillion.

The 59 cases of herpes labialis included active disease only. No attempt was made to obtain a history of recurrent herpes labialis.

Odd tongues (Prevalence of lingual disease). Bouquot JE, Gundlach KKH, West Virginia University and University of Hamburg, Hamburg, West Germany.

Presented to the American Academy of Oral Pathology, Toronto, Canada, May, 1986.
Reference: Dent Abst 32:89-90, 1987.

Data collected from oral cancer screening examinations of 23,616 adults age 35 and older in Minnesota between 1957 and 1973 were analyzed to produce prevalence rates of lingual disease in 1,000 persons.

Because there were no statistically significant age, race, or gender differences between the various groups of examinees, this group can be considered to have been examined in a single, massive oral screening. (A summary of larger prevalence of tongue lesions worldwide is shown in the Table.)

The sample population was deliberately biased toward older persons. More than 91% were age 40-79. Males were also under-represented. Only 35.9% of participants were males, while the collective proportion of males over age 30 in these communities was 46.9%.

Of a total of 3,783 reported lesions of the oral mucosa and connective tissue, 628 (16.6%) were located on the tongue, providing an overall point prevalence rate of 26.6 tongue lesions per 1,000 persons examined. Exclusion of lesions reported in such ambiguous terms as "lesions" or erythematous patch" (10.2% of lingual diagnoses) resulted in a corrected prevalence rate of 23.9 specific lesions per 1,000 population.

Lingual disease was somewhat more prevalent in males (27.3/1,000) than females (22/1,000), predominantly due to higher frequencies of squamous papillomas, hyperplastic lingual tonsils, and hairy tongues. Altered mucosal surface was the most common clinical presentation, representing 51.4% of all lesions. Almost 27% of lesions were exophytic, nonvascular soft tissue masses. Vascular lesions, exophytic or otherwise, accounted for 18.8% of all lesions. Only 2.1% of lesions were ulcerative or vesiculobullous in nature and 1.4% were cystic. A surprisingly small number of different diagnoses were rendered (no. = 27) and the five most common entities represented 62.9% of lesions.

Rates determined from this analysis are, as a rule, lower than those from other disease-specific studies. The best explanation is related to a lower level of suspicion from the use of general practitioners as examiners and from the basic function of the screenings themselves. It is likely that only the more remarkable or severe cases of these common abnormalities were reported by examiners. However, these rates are probably more indicative of disease frequency as perceived in the general practice of dentistry, because a general practitioner would be unlikely to record very small or borderline lesions of such innocuous entities.

Common oral lesions found during a mass screening examination. Bouquot JE. West Virginia University, Morgantown, WV.

Reference: Year Book of Dent 1987:275-277.

The results of oral examination of more than 32,000 adults seen at 17 mass oral screenings in Minnesota from 1957-1972 were reviewed. A total of 23,616 examinations were available for review. Most subjects were aged 35 years and older and were attending oral cancer screening clinics voluntarily. The mean age was 56 years. All but 0.5% of the ample were white; 36% were men.

A total of 3,783 oral mucosal and connective tissue lesions were reported (Table 1). The most frequent lesions are ranked by location-specific and gender-specific prevalence rates in Table 2. About 10% of the study population had oral and connective tissue lesions. A single exophytic mass accounted for more than one third of all lesions. White keratotic lesions accounted for more than one third of mucosal surface alterations. Fourteen percent of leukoplakias were epithelial dysplasias, and 12% were early invasive squamous cell carcinomas. About half other inflammatory ulcers were considered traumatic ulcers, often related to denture wear, but 40% were aphthous ulcers. Two of the 16 ulcers biopsied showed squamous cancer. Squamous cell carcinoma ranked 24^th overall among all types of lesions. Just over 30% of lesions described clinically as probable or possible carcinomas were confirmed as neoplastic.

About 10% of this screening population were found to have oral mucosal and connective tissue lesions. An exophytic mass was the most frequent clinical finding. The most common oral connective tissue-mucosal lesions was leukoplakia. Very mild common oral lesions are probably not reported in mass screenings.

Bouquot and Gorlin (Oral Surg. Oral Med, Oral Pathol. 61:373-381, April, 1986) reported in more detail some aspects of this study. They recognize as shortcomings of the study using multiple examiners who were not specialists in diagnosis and excluding equivocal and ambiguous diagnoses which may have led to underreporting. They suggest that the use of volunteers who come to cancer clinics because of unusual physical changes may compensate for underreporting by the examiners.

The American Dental Association has conducted a health assessment program for dentists registered at its annual meetings for several years. For 7 years (1977-1983) 7,041 head, neck, and oral examinations were made by the dental staff of the Veterans Administration. A total of 484 abnormalities were detected (354 intraoral and 130 extraoral), including 35 leukoplakias, 14 lichen planus, 6 pleomorphic adenomas, 2 melanomas, and 6 myoblastomas intraorally. Extraorally 33 lesions appeared as basal cell carcinomas, 1 as squamous cell carcinoma of the lip, 12 as actinic keratoses, and 2 as melanomas. Seven lesions were confirmed as carcinomas (Goltry and Ayer: JADA 112:338-341, March 1986). -abstracted by H.B.G. Robinson, D.D.S., M.S.

Table 1. - The 3,783 oral mucosal and connective tissue lesions found in 23,616 adults are categorized according to each lesion's clinical appearance, and gender-specific prevalence rates per 1,000 people are reported for each category.

Table 2. - The most common oral connective tissue and mucosal lesions are ranked according to location- and gender-specific prevalence rates.

Epidemiology of carcinoma in situ of the upper aerodigestive tract. Bouquot J, Gnepp D. West Virginia University, Morgantown, WV, and St. Louis University, St. Louis, MO, U.S.A.

Reference: J Oral Pathol 1988; 17:433.

Epidemiological analyses of upper aerodigestive tract (UAT) carcinoma in situ are non-existent, hence only hospital records and surgical pathology resources are available for its descriptive characterization. The National Cancer Institute's Surveillance, Epidemiology and End Results investigation has, however, published valuable raw data pertaining to CIS of the UAT. This information is analyzed here and summarized for the first time, demonstrating the following: a male incidence rate which is 4 times greater than the female rate (0.8/1000,000 males versus 0.2/100,000 females); similar ages at diagnosis for both sexes (62.7 and 60.0 years of age for males and females, respectively); no significant urban/rural incidence differences; that CIS represents 2.8% of all UAT malignancies; that 2.0% of all CIS lesions in humans are found at UAT sites; and that CIS of the uterine cervix is not a good model for CIS of the UAT.

Multiple carcinomas of the mouth & throat; the 54-year experience of an entire U.S. community. J. Bouquot, L. Weiland, L. Kurland. West Virginia U., Morgantown, West Virginia, and Mayo Clinic, Rochester, Minnesota.

Presented to the American Academy of Oral Pathology, San Francisco, California; May, 1992.  
Reference: Oral Surg Oral Med Oral Pathol 1992; 74: 602.

Hospital-based investigations have concluded that as few as 1% and as many as 40% of mouth and throat cancer patients develop additional primary carcinomas of these mucosal sites. Such a wide variation probably reflects differing patient referral patterns of individual hospitals more than real differences in risk, but no population-based data have been available for comparison. The present study is the first to identify all cases or oral, pharyngeal and laryngeal carcinoma in a well-delineated population in order to determine the relative frequency and characteristics of multiple cancers in an unbiased patient sample. Medical records of Rochester, MN residents diagnosed with these cancers between 1935 and 1988 were retrieved from all primary-, secondary-, and tertiary-care hospitals where Rochester residents may have gone for care. Of 292 primary mucosal carcinomas of the upper aerodigestive tract (excluding lip vermilion) identified in 259 residents, 25 lesions in 22 persons were additional primaries of those sites (39 of 339 cancers if lip vermilion is included). Thus multiple primaries occurred in only 8.5% of UAT carcinoma patients, 12%, 8% & 6%, RESPECTIVELY, OF laryngeal, oral and pharyngeal carcinomas were second or third primaries. Also, 58% (n=14) were synchronously diagnosed. Clinicopathologic data will be presented.

Incidence of oral verrucous carcinoma in a U.S. community with minimal smokeless tobacco consumption.  J. Bouquot, L. Weiland, L. Kurland. The Maxillofacial Center, Morgantown, West Virginia; Mayo Clinic West, Phoenix, Arizona, Mayo Clinic, Rochester, Minnesota.

Presented to the International Association of Oral Pathologists, Toronto, Canada; July, 1996.  
Reference: J Oral Pathol Med 1996; 25:271.

Objective: To determine the annual incidence rate for verrucous carcinoma of the mouth and throat. Method: A population-based incidence cohort study covering a 50 year time period was conducted in the community of Rochester, Minnesota. All upper aerodigestive tract carcinomas diagnosed in this community from 1935 to 1985 were identified through the Mayo Clinic's record-linkage system. Incidence and relative frequency rates were calculated from this data. Results: Verrucous carcinoma represented 3.3% of all oral carcinomas. The age-adjusted average annual incidence rate was 0.1/100,000 person-years (0.2 for males, 0.0 for females). The incidence rate for all intraoral carcinomas was 3.1/100,000 (4.2 for males; 2.1 for females). Among males over 64 years of age the incidence rate for verrucous carcinoma was increased to 3.2/100,000 person-years. Verrucous carcinoma was more common than intraoral melanoma, basaloid squamous carcinoma or adenosquamous carcinoma, but four times less common than intraoral carcinoma in situ. This is the first incidence data for this disease.