The epidemiology of oral cavity, pharyngeal and esophageal cancer outside of North America and Western Europe

Treatment outcome of advance staged oral cavity cancer: concurrent chemoradiotherapy compared with primary surgery

Concurrent chemoradiotherapy (CCRT) has been reported as effective and has become an acceptable treatment in advanced oral cancer. However, to date there is insufficient data to conclude that CCRT provides a good survival outcome. The purpose of this study was to compare survival rates and complications in patients with resectable advanced oral cavity squamous cell carcinoma treated with either CCRT or surgery with adjuvant radiotherapy (RT)/chemoradiotherapy (CRT). Stage III or IVa oral cavity carcinoma patients treated with curative intent by either CCRT or surgery with adjuvant RT were identified over a 7-year period (2009-2015). Survival rates and treatment complications were analyzed and compared between the two groups. 61 patients underwent CCRT and 128 patients underwent surgical excision and received postoperative RT. There was no statistically significant difference in survival outcome between the two treatment groups. 5-year overall survival rates (OS) were 33 versus 24% (P = 0.191) and the disease-specific survival rates (DSS) were 27 versus 25% (P = 0.857) when comparing the CCRT group and surgery with adjuvant RT/CRT group, respectively. Long-term complications were comparable between the two groups. CCRT has comparable survival outcome and complications for the treatment of advanced oral cavity squamous cell carcinoma, compared to surgery with adjuvant RT/CRT.

High urine 1-hydroxypyrene glucuronide concentrations in Linxian, China, an area of high risk for squamous oesophageal cancer

Most squamous cell carcinomas of the oesophagus in low-risk populations are attributable to alcohol and tobacco consumption, but the aetiologic agents in many high-risk populations have yet to be definitively identified. Linxian, China has some of the highest oesophageal cancer rates in the world. Recent studies suggest that an association exists between high-level exposure to carcinogenic polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene (B[a]P), and the development of oesophageal cancer. The inhabitants of this high-risk region extensively use coal and wood for cooking and heating in unvented stoves, and thus may be exposed to PAHs produced during the incomplete combustion of these fuel sources. High levels of B[a]P were recently detected in staple food samples from Linxian and histopathologic changes that may be associated with PAH exposure have also been identified in oesophagectomy specimens from the region. In an effort to determine whether this high-risk population is exposed to high levels of PAHs, voided urines from non-smokers (n = 22) without occupational exposure were collected and analysed using immunoaffinity chromatography and synchronous fluorescence spectroscopy for 1-hydroxypyrene glucuronide, a PAH metabolite and index biomarker for mixed PAH exposure. The median urine 1-hydroxypyrene glucuronide concentration (2.06 pmol ml(-1)) was equivalent to concentrations detected in current smokers. To the authors' knowledge, this represents the first report of elevated urine 1-hydroxpyrene glucuronide concentrations in Linxian, and the first biologic confirmation that the inhabitants of this rural, non-industrial, high oesophageal cancer risk region are exposed to carcinogenic PAHs.

Intraoral squamous cell carcinoma. Epidemiologic patterns in Connecticut from 1935 to 1985

There were 6181 cases of invasive intraoral squamous cell carcinoma accessioned by the Connecticut State Tumor Registry from 1935 to 1985. Cases were analyzed for age, sex, lesion site, and histologic differentiation. Crude, age-specific, and age-adjusted incidence rates plus birth cohort analyses were also calculated. It was found that incidence rates for both men and women increased over the 51-year period of study. For men, age-adjusted incidence rates (1970 United States standard) increased from 4.9/100,000 in 1935 to 1939 to 8.5/100,000 in 1980 to 1985; for women, rates increased from 0.5/100,000 to 3.3/100,000 for the same period. The male-to-female ratio for intraoral squamous cell carcinoma declined dramatically from 9.8 to 2.6 during the 51-year study period primarily because of the steep rate of increased incidence in women relative to that seen in men. The peak age of intraoral squamous cell carcinoma was the seventh decade. Age-specific analysis showed that the older the age group, the higher the incidence for both sexes. During recent years, there was evidence of slightly increased incidence in men younger than 40. The tongue was the most common site for intraoral squamous cell carcinoma, followed closely by the floor of the mouth. Moderately differentiated tumors were most common (54.3% of the total), followed by both well-differentiated cases (29.1%) and those that were poorly differentiated (16.6%).

Epidemiology of oral cancer in Connecticut, 1935 to 1985

All cases of oral cancer (N = 9708) recorded by the Connecticut Tumor Registry from 1935 to 1985 were analyzed for time-trend patterns within 10-year age-groups. Crude, age-specific, age-adjusted incidence rates and birth cohort analyses were calculated. The average annual age-adjusted incidence rate was 12.9/100,000 for men and 2.9/100,000 for women (1970 US standard million population). The male age-adjusted incidence rate decreased 33% from the late 1930s to the early 1980s. The female age-adjusted incidence rate exhibited a threefold steady increase over this same time period. The male/female ratio for oral cancer incidence declined dramatically from 10.4 to 2.7 for the age-adjusted rate, nearly a fourfold decrease during the 51- year period. Birth cohort analyses for women indicated a marked increase in oral cancer incidence for the birth cohort of 1900, which was sustained in the birth cohorts that followed. Birth cohort analyses for men revealed a decline in oral cancer incidence for birth cohorts born after 1910. The highest incidence rates were found in the urban counties and the lowest in the rural areas.

Etiology of oral squamous cell carcinoma

The traditional list of etiological factors related to oral squamous cell carcinoma namely, tobacco, alcohol, syphilis, and oral sepsis has been expanded to include iron deficiency, chronic candidosis, and herpes simplex virus. The development of current concepts in these areas is discussed. In evaluating the need for future research, special emphasis is given to the concepts of multifactorial etiology and the role of mutagens. Suggestions for future research are discussed.