¾ Oral squamous cell carcinoma (OSCC) constitutes approximately 94% of all malignant lesions in the oral cavity

(1)

口腔病理科 On-Line KMU Student Bulletin

原文題目(出處)： Oral squamous cell carcinoma incidence by subsite among diverse racial and ethnic populations in California. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008;105:470-80

原文作者姓名： Lihua Liu, Satish K. S. Kumar, Parish P. Sedghizadeh, Abheer N.

Jayakar, Charles F. Shuler

通訊作者學校： UNIVERSITY OF SOUTHERN CALIFORNIA, LOS ANGELES

報告者姓名(組別)： Intern J 周建安 報告日期： 97.05.13 內文：

Introduction

¾ Cancer of the oral cavity occurs more frequently among men than women.

¾ Two thirds of all cases are observed in developing countries.

¾ Oral squamous cell carcinoma (OSCC) constitutes approximately 94% of all malignant lesions in the oral cavity.

¾ Each year more than 22000 new cases of OSCC and more than 5000 deaths from OSCC occur in the United States alone.

¾ 5-year survival rates approaching approximately 60% in white Americans and only 40% in African Americans.

MATERIAL AND METHODS

¾ Examine the oral cancer incidence rate by anatomical subsite and race/ethnicity among residents in California during 1988 to 2001.

¾ Non-Hispanic (NH) white, NH black, Hispanic, Chinese, Japanese, Filipino, Korean, South Asian (including Asian Indian, Pakistani, Bangladeshi, and Sri Lankan), and Vietnamese.

¾ International Classification of Diseases for Oncology, 3rd edition (ICD-O-3): oral tongue (C02.0-C02.9), gum (C03.0-C03.9), floor of mouth (C04.0-C04.9), palate (C05.0-C05.9), and other mouth (C06.0-C06.9) that included other subsites of the mouth such as the buccal cavity.

¾ The SEER*Stat software, version 6.2.4 (National Cancer Institute, Bethesda, MD) was used for statistical calculations of age-adjusted incidence rates, rate ratios, and 95% confidence intervals (CIs) for the rate or rate ratio estimates.

RESULTS

¾ For the oral cavity as a whole, NH black males have the highest age-adjusted incidence rate (AAIR) for OSCC among males (4.86/100 000), followed by NH whites males (4.71/100 000).

¾ For women, the highest AAIR is among South Asians (2.97/100 000), followed by NH whites (2.76/100 000).

¾ The OSCC incidence rate for Hispanics is much lower than that of the NH whites or blacks (2.52/100 000 men, 1.38/100 000 women).

¾ The highest M:F ratio is found in NH blacks.(2.77).

(2)

Tongue

¾ The oral tongue is the most common subsite for OSCC in every race/ethnicity.

¾ NH white men have a slightly higher AAIR than NH black men for tongue cancer.

¾ The M:F rate ratio for NH blacks is 2.96, as compared with 1.74 of NH whites.

¾ Tongue cancer occurs more frequently among Filipino and Chinese women than men.

Gum

¾ The gum (gingiva) is the least common subsite for OSCC.

¾ NH whites appear to have the highest incidence rates in both men (0.44/100 000) and women (0.37/100 000).

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Floor of mouth

¾ The floor of mouth is the second most common subsite for OSCC.

¾ NH black men have the highest AAIR (1.83/100 000), followed by NH white men (1.40/100 000) and Hispanics (0.82/100 000).

¾ Filipinos and Japanese display higher AAIRs among the Asians.

Palate

¾ Similar to the gum, the palate is a less frequent subsite for OSCC.

¾ The highest AAIR for OSCC of the palate, 1.03 per 100 000, is observed among NH black men.

¾ Chinese have the highest M:F ratio.

(4)

Other mouth

¾ This is the second most common OSCC subsite after oral tongue for all Asian groups except Filipinos.

¾ The highest M:F rate ratio of 3.72 for OSCC in this category is found among South Asians, whereas the lowest is among Japanese

The patterns of AAIRs of OSCC by race/ethnicity for each subsite included in the study demonstrate that NH whites and blacks have similar incidence rates, but the M:F ratio is higher among NH blacks.

The OSCC incidence rates for Hispanics are much lower than those for NH whites and NH blacks.

(5)

The Asian subgroups display dramatic variations in terms of subsite distribution, incidence rate levels, and M:F ratios.

DISCUSSION

(1) There are marked differences in oral cancer risk (as indicated by AAIR) between different racial/ethnic populations.

(2) The risk of developing cancer varies by the location inside the oral cavity.

¾ Although many lifestyle factors are associated with the development of oral cancer (e.g., poor nutrition, suppressed immune system, human papilloma virus [HPV] infection, and dental irritation), about 75% of oral cancer is attributable to tobacco use and alcohol consumption.

¾ The dehydrating effect of alcohol on cell membranes enhances the ability of tobacco-associated carcinogens to permeate mouth tissues; in addition, nutritional deficiencies associated with heavy drinking can lower the body’s natural ability to use antioxidants to prevent the formation of cancer.

¾ There were 17 palatal OSCC cases in Filipino females and just 1 case in males.(reverse smoking)

¾ Studies have shown that tobacco use and alcohol intake do not completely explain tongue cancer incidence rates, and factors such as HPV infection may also contribute to the rise in tongue cancers.

CONCLUSION

The differences in incidence rate by sex, race/ethnicity, and subsite illustrate the heterogeneity of the disease by anatomical location, as well as the impact of varied cultural and behavioral factors in the development of the disease in different ethnic populations.

題號題目

1 下列何者最不可能是口腔癌相關病因

(A) 缺鐵性貧血 (B) 梅毒 (C) 免疫抑制 (D) 遺傳

答案(D) 出處：Oral and maxillofacial pathology, 2^nd edition,p.356-359 題號題目

2 下列何者屬口腔癌前期的病變

(A) Fibroma

(B) Squamous cell papilloma (C) Verruciform xanthoma (D) Oral erythroleukoplakia

答案(D) 出處：Oral and maxillofacial pathology, 2^nd edition,p.341-342