On 180 Biopsies of Oral Carcinomas in Our Department of Pathology by Yasuyuki AWAZAWA * and Itaru MORO * Introduction Carcinomas in the oral region, like those found in other regions of human body, have differences owing to sex, age, spot of primary origin, etc., in terms of their frequency. Observations of these differences are, therefore, full of significance not only from a clinical point of view as providing an exact diagnostic tool, but also from a pathological standpoint in that it makes clear peculiarities of various types of the oral carcinomas. Another significance of these observations lies in our better understanding of preventive measures against the oral carcinomas and the determination of histologic types of them is also meaningful. From these considerations, the authors collected 312 tumor cases during 14-year biopsies from August 1952 to December 1966 in the Department of Pathology, Nihon University School of Dentistry, and of them a selection was made of 180 which were malignant epithelial tumors for observation purposes here. These specimens were statistically treated in terms of a) frequency, b) sex, c) age, d) spot of origin, histologic types and so forth. The present study may prove worthwhile to acquaint the oral surgeons and general clinicians with the data regarding the incidence of oral carcinomas in the Japanese. Materials and Survey Results During 14-year period above mentioned, a total of 856 materials underwent our biopsies and these consisted of those from our own dental infirmary, those referred to us by the departments of surgery, gynecology, etc. of Nihon University Surugadai hospital and other public and private medical and dental clinics. Nearly half (483) of these bioptic materials were in the dental field. Of these, tumors accounted for 312 and they were further broken down into 109 benign tumors and 203 malignant tumors, the latter being subdivided into 180 carcinomas and 22 sarcomas (Table 1). 1) Frequency of incidence. As against a total of 483 bioptic materials in the dental field, the incidence of tumors accounts for 65% and a ratio of the tumors to the former is 1.6 : 1. When we compare the frequencies of benign (109) and malignant (203) tumors, the former accounts for 54% of the latter with a ratio of 1.9 : 1. As known from Table 1, the frequency of sarcomas is 12.2% of carcinomas with a ratio of 8.2 : 1.
TABLE 1 Classification of Tumor Cases during 14-year Biopsies from August 1952 to December 1966 in the Department of Pathology, Nihon University School of Dentistry TABLE 2 Frequency of Incidence of Oral Carcinomas owing to Sex and Age TABLE 3 Frequency of Incidence of Squamous Cell Carcinoma in Oral Region owing to Sex and Age Keratinized type: 88 cases, non-keratinized type: 75 cases, basal cell carcinoma: 3 cases.
Fig. 1. Squamous-cell carcinoma of palate extending from alveolar process. Infiltrative character is noted. 67 year old male patient. Fig. 2. Squamous-cell carcinoma of the floor of the mouth showing epithelial pearls. 44 year old female patient. 180 carcinomas comprise 166 squamous cell carcinomas which account for as much as 92.2% of the entire number (Tables 2, 3). 2) Differences owing to sex and age. a. Squamous cell carcinoma. This type of malignant tumor covers from 20's to 90's age brackets. The highest frequency is in 50's, order being 60's, 40's, 70's and 30's in descending scale. The minimum age is 26 (male) and 24 (female) respectively, whereas the maximum age is 80 (male) and 90 (female) (Table 3). In terms of average ages, that of males is 57.5 years and 54.2 years for females with the mean of both sexes being 56.3 years. By way of sex difference, 111 are found in males and 55 in females, which is indicative of the fact that a ratio between the sex is nearly twice (Table 3). b. Adenocarcinoma or malignant epithelioma of the salivary gland. It is found in every age decade with the exception of 20's. High frequency is noted in 50's to 60's age brackets. In terms of average ages, male is 54.8 years and 50.5 years for female, the average age of both sexes being 52.7 years. However, there is no difference in frequency of incidence by way of sex (Table 4). Fig. 3. Squamous-cell carcinoma of alveolus in mandible. Well-differentiated tumor tissue representing diffuse keratinization. 54 year old female patient. Fig. 4. Basal-cell carcinoma of alveolus in mandible. 40 year old female patient.
3) Spot of origins. a. Squamous cell carcinoma. This type of carcinoma is most frequently found in the gingiva, where it is oftener encountered in the upper rather than the lower jaw. The ratio between the upper and lower gingivae is 1.6: 1. TABLE 4 Frequency of Incidence of Adenocarcinoma or Malignant Epithelioma of Salivary Gland according to Sex and Age TABLE 5 Frequency of Incidence of Squamous Cell Carcinoma owing to Spot of Origins TABLE 6 Frequency of Incidence of Squamous Cell Carcinoma in Oral Area according to Spot of Origins * Each figure in the table indicates case number of incidence.
As compared with 166 squamous cell carcinomas in the oral region, 116 are claimed by those of upper and lower gin givae with a percentage of 69.9 % (Table 5). Table 6 indicates different spots of oral squamous cell carcinomas with re- TABLE 7 ference to their frequency principally in terms of gingivae in the upper or lower jaw, left or right in the anterior, premolar and molar regions. It is to be noted that a greater portion of this malignant carcinoma is found in the molar gingiva in common with the upper and lower jaws, where the upper molar gingiva claims nearly twice as much as that of lower molar gingiva. Frequency tends to be less from the molar, premolar to anterior tooth regions. As regards the premolars, the right side has a higher frequency than the left. An interesting phenomenon is noted that, except for the molars, there is no difference in frequency of incidence between the upper anteriors and premolars and those of the lower jaw. b. Adenocarcinoma or malignant epithelioma of the salivary gland. Order of their frequency is the palate (6 cases), upper gingiva (3), ramus man.- dibulae (2) and parotid gland (1). Frequency in the palate is as much as 50 % (Table 7). Frequency of Incidence of Adenocarcinoma or Malignant Epithelioma of Salivary Gland owing to Spot of Origins Fig. 5. Carcinoma of tongue. Groups of tumor cells are separated by stroma in a manner of alveolar structure. 53 year old male patient. Fig. 6. Carcinoma of tongue. Mitotic figure is noted. 51 year old male patient. Fig. 7. Carcinoma of tongue. Relatively well keratinized type showing an epithelial pearl. 48 year old male patient.
4) Histologic types of carcinomas. a. Squamous cell carcinoma. 88 cases are determined to be keratinized type and 75 are non-keratinized type with no significant difference between the two types. Besides, there are noticed 3 cases of basal cell carcinoma (Table 8). TABLE 8 Relationship between Ages and Histologic Types regarding Incidence of Malignant Epitheliomas of Salivary Glands b. Adenocarcinoma or malignant epithelioma of the salivary gland. Adenocarcinomas (5 cases) are found in 50's to 70's age bracket. 2 cases of cancroid and 2 cases of adenoid cystic carcinoma are respectively found, the former being in 50's to 60's age bracket and the latter in 40's to 50's age bracket. In addition, there are respectively 1 case of mucoepidermoid tumor (50's year bracket), clear-cell carcinoma (10's), and carcinoma simplex (Table 8). Other 2 cases of carcinoma simplex are found in the upper gingiva, both being males of 62 and 65 years old respectively (Table 1). In the latter portions presenting medullary carcinoma are found. Discussion The type of oral carcinoma that has the highest frequency in our examination is that of squamous cell carcinoma with a percentage of 92.2 %. This percentage distribution is more or less in keeping with the available literature. ONO [1] gave a finding of 283 squamous cell carcinomas (94.3 %) in 300 cases of the entire oral carcinoma, while SOEJIMA [2] found 87 squamous cell carcinomas (96.7 %) in 90 cases of the oral carcinoma examined. SHIOTA et al. [4], however, reported a somewhat low percentage of 78.0 % squamous cell carcinomas in 60 cases of the entire oral carcinoma. Our finding of the oral carcinomas being most frequent in 50's age bracket in both sexes with 32.2 % distribution. This fact is also endorsed by the respective re - ports of ONO [1], OTANI [3] and YAMADA et al. [5] who gave 35.4 %, 31.8 % and 32.2 %. SHIOTA et al. [4] gave the average age of both sexes as 52.6 years old. Similarly, UENO et al. [6] who examined 265 maxillary carcinomas found the age bracket of 50's most frequent with 28.3 % distribution. With their study of 97 cases
Fig. 8. Squamous-cell carcinoma of maxillary sinus. Irregular and disorderly arrangement of epithelial cells is noted and many of them are atypical. 63 year old male patient. Fig. 9. Malignant epidermoid tumor of parotid gland. 59 year old male patient. Fig. 10. Adenocarcinoma of alveolus in maxilla. 53 year old female patient. Fig. 11. Mucoepidermoid tumor, malignant type. 54 year old male patient. of oral carcinomas, OTANI et al. [ 7 ] gave the range of 40's to 60's years to be most frequent. When the incidence frequency of these oral carcinomas is examined in terms of sex, the male registers twice as often as the female in our survey. Other native investigators gave more or less similar findings : ONO [ 1 ] gave the male to be 2.6 times than the female, OTANI [ 3 ] and MIYAZAKI et al. [ 8 ] respectively gave 1.7 times and YAMADA et al. [ 7 ] reported the frequency of 1.8 times on the part of the male. As compared with the Japanese data, we note that the incidence of oral carcinomas among the Europeans and Americans is somewhat more advanced in age. According to LEDLIE and HARMER [ 9 ], nearly 75 % of the British patients of oral carcinomas were over 60 years old and the male had 9 times as frequent as the female in the incidence of oral carcinomas. It may be of interest to compare below the average age of patients in which the oral carcinomas are most frequent (Table 9). In terms of origins, the majority of our cases were found in the upper and lower jaw gingivae, the rest being in order of the palate, tongue, floor of the mouth and buccal mucosa (Tables, 5, 7). The difference of incidence between the upper and lower gingivae is 1.6 : 1. According to the published literature [ 8 ], the major point of difference between the Japanese and the Europeans and Americans in this respect is that
TABLE 9 Comparison of Average Ages in Highest Oral Carcinoma Frequency TABLE 10 Comparison between our Findings and Those of OTANI regarding Histologic Types of Oral Carcinomas in the latter carcinomas are most frequently found with the lips and buccal mucosa. Classified in terms of histologic types, our findings can be most conveniently contrasted with those of OTANI [12] as shown below in Table 10. While a ratio of keratinized type to non-keratinized type in our survey is 1.2 : 1, OTANI gives a ratio as wide as 3.1 : 1. There is not seen an appreciable difference between our 6.7 % and 5.3 % of OTANI, indicative of a ratio of adenocarcinoma or Fig. 12. Adenoid cystic carcinoma. 52 year old male patient. Fig. 13. Clear-cell carcinoma of alveolar process in maxilla. 18 year old female patient.
105 Fig. 14. Carcinoma simplex of palate in maxilla. 36 year old male patient. Fig. 15. Medullary carcinoma of alveolar process in maxilla. 65 year old male patient. malignant epithelioma of the salivary gland to the total number of carcinomas. ONO [1] reported 6 malignant mixed tumors of salivary gland out of 350 cases of the entire oral carcinomas. This ratio accounts for as much as 1.7% of the carcinomas in the oral region. As has been discussed above, the findings of our present survey are more or less in line with the previously published data by other native researchers. Conclusions 1. 180 cases of the oral carcinomas, from those collected by the Department of Pathology, Nihon University School of Dentistry, over 14 years, were selectively examined as regards the sex, age, spot of origins and histologic types. 2. Of 180 oral carcinomas, 166 are squamons cell carcinomas (92.2%), 12 are malignant epitheliomas of the salivary gland (6.0%) and 2 are cases of carcinoma simplex. 3. Various statistical data do not suggest any significant difference among the Japanese but there are certain points in which the Japanese markedly differ from the Europeans and Americans. References [1] ONO, S. : On 350 cases of malignant tumors in the oral region, J. oral. Surgery, Soc. Japan., 5 : 102-105, 1959. (in Japanese) SOEJIMA, T. : Statistical observations of benign and malignant tumors in our department, Koku-Kagaku, 6: 467-477, 1938. (in Japanese) OTANI, T. : Clinico-pathological studies on the oral carcinoma, Part One, J. Jap. stomatol, Soc., 19 : 126, 1952. (in Japanese) SHIOTA, K. et al. : 422 bioptic materials examined in past 4 years by our department, J. Jap. stomatol, Soc., 6: 437-443, 1957. (in Japanese) YAMADA, N. et al. : Clinical and statistical observations of malignant tumor patients in past 13 years in our department, J. oral. Surg. Soc. Japan., 6 : 366-370, 1960. (in Japanese) UENO, T. et al. : Studies on the treatment and prognosis of the oral carcinomas, Part Two, J. oral. Surg. Soc. Japan., 6: 407-516, 1960. (in Japanese) OTANI, T. et al. : Statistical observations of our oral carcinoma patients in past 5 years,
106 J. Jap. stomata Soc., 6: 272-273, 1957. (in Japanese) MIYAZAKI, Y. et al. : Oral Pathology, Nagasuye Pub. Co., Kyoto, 1958. (in Japanese) LEDLIE, F. M. and HARMER, M. H. Cancer of the mouth ; a report on 800 cases, Brit. J. Cancer, 4: 6-18, 1960. WILLIS, R. A.: Pathology of Tumors, 2nd edition, Butterworth and Company, London, 1953, p. 18. TIECKE, R. W. and BERNIER, J. L. : Statistical and morphological analysis of four hundred and one cases of intraoral squamous cell carcinoma, J. Amer. dent. Assoc., 49: 684-698, 1954. OTANI, T. : Clinico-pathological studies on the oral carcinoma, Part Three, J. Jap. stomatol, Soc., 21 : 7-16, 1954. (in Japanese)