Incidence of oral cavity and pharyngeal cancers by anatomical sites in population-based registries in Puerto Rico and the United States of America.

OBJECTIVE: Puerto Rico's (PR) epidemiological data on each oral cavity and pharynx cancer (OCPC) site is yet largely unexplored. Our aim was to compare OCPC incidence in PR, by anatomical site, with that of non-Hispanic whites (NHW), non-Hispanic blacks (NHB), and Hispanic (USH) individuals in the USA. METHODS: Data from the Surveillance Epidemiology and End Results program and the PR Central Cancer Registry were collected and analyzed. Age-standardized rates, percent changes, and standardized rate ratios were estimated with 95% confidence intervals. RESULTS: Although declining incidence rates were observed for most anatomical sites in most racial/ethnic groups and in both sexes, the incidence of oropharynx cancers slightly increased for cancers in the oropharynx among PR women, both in the base of tongue and soft palate/other oropharynx (p>0.05). The incidence of soft palate/other oropharynx cancers in PR men was about 2.8 times higher than in USH men (p<0.05) and about 1.4 times higher than in NHW men but 21% lower than in NHB men (p>0.05). Significant interactions terms formed with racial/ethnic group and age were shown in various sites. The largest differences between sexes were consistently noted in PR. CONCLUSION: Further research in PR should assess the effect of the HPV infection, as well as of other risk factors, in OCPC incidence by anatomical site in younger populations. These data could explain more precisely the reasons for the differences observed in this study, particularly among sexes in PR.

Trends in palatine tonsillar cancer incidence and mortality rates in the United States.

OBJECTIVE: The purpose of this paper is to describe the extent of the public health problem presented by palatine tonsillar cancer in the United States by analyzing recent incidence and mortality rate trends. METHODS: Using the National Cancer Institutes' Surveillance, Epidemiology and End Results (SEER) Program database, age-adjusted incidence rates (1973-2001) for five histological types of palatine tonsillar cancer by race and sex were calculated. For total palatine tonsillar cancer age-specific incidence (1973-2001) and mortality (1969-2001) rates by race and sex were calculated. Mortality and population data were obtained from the National Center for Health Statistics (NCHS) and the U.S. Census Bureau. The Joinpoint Regression Model was employed to establish the statistical significance of incidence and mortality rate trends. RESULTS: The majority of palatine tonsillar cases diagnosed in SEER-9 registries from 1973 to 2001 occurred among white males, age 40-64 years, with squamous cell carcinoma (SCC). The highest incidence of palatine tonsillar cancer occurred in black males, followed by white males with SCC. For age 40-64 years, palatine tonsillar incidence rates significantly declined for white females and black females, rose and then declined for black males, but increased from 1988 for white males. For age 65+ years, incidence significantly declined among white males. Palatine tonsillar cancer mortality rates for age 40-64 years significantly declined for white females. Rates also declined for black females (1981-2001) and black males (1985-2001) in this age group while rates for white males declined significantly from 1969 to 1987, but stabilized at nearly 0.4 through 2001. Mortality for the age group, 65+, significantly rose and fell for white females and declined for white males. CONCLUSIONS: Beginning in the late 1980s, and continuing through 2001, the risk for white males, age 40-64 years, of developing palatine tonsillar cancer increased. In contrast, the risk for white males, age 65 years and older, of developing palatine tonsillar cancer and of dying from this disease decreased during the study period.

Surveillance of Tonsillar Cancer Incidence Rates in Minority Groups vs Non-Hispanic Whites in Large US Metropolitan Areas.

BACKGROUND: For oropharyngeal (OP) cancers at anatomical sites regarded as related to human papillomavirus (HPV), surveillance using population-based cancer registries has shown that age-standardized incidence rates are higher in US non-Hispanic whites (NHWs) vs minority groups. Surveillance in large racially-ethnically diverse urban areas also should be considered. METHODS: Using the US Cancer Statistics database, age-standardized incidence rates per year were obtained for 2003­2013 for carcinomas of the tonsil, the OP site most strongly associated with HPV. Data were available for NHWs, non-Hispanic blacks (NHBs), and Hispanic whites (HWs) in 20 large metropolitan statistical areas (MSAs), and for Asian-Pacific Islanders in 8 of these MSAs. Trends in annual rates were examined using join-point regression. RESULTS: The overall rate (2003­2013) was higher for NHWs vs each minority group in almost all MSAs. Little or no NHW­NHB difference was found in 3 MSAs, using abbreviated titles: San Francisco, with a relatively high rate for NHBs; San Diego, with high rates for both groups; and Detroit, with a low rate for NHWs and a high rate for NHBs. For individual MSAs with sufficient data for trends in at least 1 minority group, rising rates for NHWs diverged from NBHs and HWs in New York, and from NHBs in Chicago but not from NHBs in Detroit. For HWs, rates increased statistically significantly in the Miami MSA, vs a smaller increase in the Los Angeles MSA and no increase in the New York MSA. CONCLUSIONS: Surveillance of OP carcinoma incidence by MSA appears justified, but should use databases that attempt to collect information on racial­ ethnic subgroups (eg, birthplace and/or ancestry for HWs).

Burden of potentially human papillomavirus-associated cancers of the oropharynx and oral cavity in the US, 1998-2003.

BACKGROUND: As human papillomavirus (HPV) vaccination becomes widely available in the US for cervical cancer prevention, it may also affect the rates of other cancers potentially associated with HPV. The objective of the current study was to describe the incidence rates of oropharyngeal and oral cavity cancers in the US with a focus on anatomic sites potentially associated with HPV infection. METHODS: Incident cases diagnosed between 1998 and 2003 identified through 39 population-based registries that participate in the National Program of Cancer Registries and/or the Surveillance, Epidemiology, and End Results Program were examined. The incidence rates of potentially HPV-associated oropharyngeal and oral cavity cancers by various characteristics were estimated. The 1998 through 2003 trends in these rates were also compared with rates for sites not previously shown to be associated with HPV (comparison sites). RESULTS: In all, 44,160 cases of potentially HPV-associated cancers of the oropharynx and oral cavity were identified, including 19,239 (43.6%) tonsillar, 16,964 (38.4%) base of tongue, and 7957 (18.0%) other oropharyngeal cancers. The incidence rates for these sites were highest among blacks, and higher among non-Hispanics and men than among Hispanics and women. The annual incidence rates of potentially HPV-associated cancers of the tonsil and base of tongue both increased significantly from 1998 through 2003 (annual percentage change [APC], 3.0; P < .05 for both sites), whereas the incidence rates of cancer at the comparison sites generally decreased. CONCLUSIONS: The results of the current study provide baseline incidence rates of potentially HPV-associated cancers of the oropharynx and oral cavity that can be compared with rates after the widespread implementation of the HPV vaccination.

Absence of human papillomavirus in tonsillar squamous cell carcinomas from Chinese patients.

Epidemiological and experimental evidence from Western countries now consistently support an etiological role for human papillomavirus (HPV) in a subset of oropharyngeal squamous cell carcinomas (SCC), especially those originating in the tonsil. The role of HPV in the etiology of tonsil cancer in developing countries such as China has not been investigated. In this study, none of 16 tonsil cancer specimens from Chinese patients were positive for HPV DNA, whereas those from Australian patients using the same methodology gave a positivity rate of 46%. The tumors from Chinese patients, like the Australian HPV-negative subset, significantly overexpressed pRb and cyclin D1 and underexpressed p16(INK4A) (p16). In contrast, the Australian HPV-positive cancers overexpressed p16 and had reduced expression of pRb and cyclin D1. These findings may help explain why China has a relatively low rate of oropharyngeal cancer compared with Australia. They also support the hypothesis that molecular pathways to tonsil cancer mediated by HPV are distinct from those induced by mutagens present in cigarette smoke or alcohol.

The site of infection and ethnicity of the patient influence the biological pathways to HPV-induced mucosal cancer.

High-risk human papillomaviruses are the causative agents of cervical cancer and are also believed to be aetiologically involved in a subset of squamous cell carcinomas of the head and neck region, especially the tonsil. Cervical cancers arise through disruption of the pathways of p53 and the product of the retinoblastoma gene by the human papillomavirus oncoproteins E6 and E7. It is generally assumed that the same pathways are involved in human papillomavirus-induced carcinogenesis at other mucosal surfaces. However, the patterns of expression of cell cycle proteins targeted by human papillomavirus E6 and E7 in cancers from different anatomic sites have been inconsistent, due to either biologic or technological factors. In this study, 73 human papillomavirus, 16-positive cervical squamous cell carcinomas (35 from Australian and 38 from Chinese women) were analysed for the expression of p53, pRb, p16(INK4A), p21(CIP1/WAF1), p27(KIP1) and cyclin D1 by semiquantitative immunohistochemistry. Cervical cancers from Chinese women were found to be significantly more likely to overexpress p53, pRb, p21 and p27 than their Australian counterparts. These findings were compared with those from 31 human papillomavirus 16-positive tonsillar squamous cell carcinomas, all of Australian origin, tested using the same methodology. Comparisons of the tonsillar and combined cervical data showed that tonsillar cancers were significantly more likely to be p53-positive, whereas cervical cancers were significantly more likely to overexpress pRb, p16 and p27. When the tonsillar data were compared with cervical data from Australian women, the associations for p53 and pRb remained. These findings represent new evidence that the molecular pathways to human papillomavirus-induced mucosal cancer may be influenced by anatomic location and ethnicity.

Human papillomavirus-associated carcinomas in Hawaii and the mainland U.S.

BACKGROUND: To the authors' knowledge, human papillomavirus (HPV)-associated carcinomas in Hawaii have not been studied in detail. METHODS: Surveillance, Epidemiology, and End Results data (from 1973-1996) were used to study rate of incidence patterns of squamous cell carcinomas (SCCs) of the uterine cervix, vulva/vagina, anus, penis, and palatine tonsils among Asian/Pacific Islanders and whites in Hawaii and among whites in the U.S. in general. RESULTS: With the exception of invasive cervical SCC, male and female Asian/Pacific Islanders in Hawaii had considerably lower incidence rates of HPV-associated SCCs than Hawaii whites and U.S. whites. Among women, Hawaii whites and U.S. whites had rather similar rates of invasive anogenital and tonsillar SCCs, but in situ SCC of the cervix or vulva/vagina was diagnosed less often among Asian/Pacific Islanders and whites in Hawaii than among whites in the general U.S. Among men, Hawaii whites had higher rates than U.S. whites of both anal and tonsillar, but not penile, SCCs. Among Hawaiian men with anal carcinoma, 43% (15 of 35) had remained unmarried versus 3% (2 of 65) of Hawaiian women with anal carcinoma. CONCLUSIONS: Asian/Pacific Islanders in Hawaii generally have lower incidence rates of HPV-associated SCCs than whites. However, low ratios of in situ to invasive cervical SCCs suggest that many Hawaii women, notably Asian/Pacific Islanders, are not diagnosed and treated for cervical neoplasias at a preinvasive stage. The high rate of incidence of anal SCC in male Hawaiian whites and the high proportions of unmarried men among patients with this disease suggest the transmission of HPV through homosexual contact. These men may be targeted in future screening programs for anal carcinoma.