CHANGING TRENDS IN ORAL-CANCER IN THE UNITED-STATES, 1935 TO 1985 - A CONNECTICUT STUDY

An extensive epidemiologic study was undertaken in an attempt to analyze patterns of oral cancer distribution and demography in Connecticut between 1935 and 1985. Sources of data for the investigation included both the Connecticut Tumor Registry (CTR) and the University of Connecticut Oral Pathology Biopsy Service. During the 51-year study period, 9,708 cases of primary oral cancer were reported to the CTR. Male age-adjusted incidence rates for overall oral cancer remained stable between 1935 and 1964 (14.5 to 14.8 per 100,000), with a gradual decline to 10.9 per 100,000 in the early 1980s. In contrast, age-adjusted rates for females advanced approximately threefold, from 1.4 per 100,000 in the 1930s to 4.1 per 100,000 in the early 1980s. There was a decrease in age-specific rates of oral cancer in males aged 70 and older; in contrast, age-specific incidence rates in females increased steadily over the same period. It was also found that female birth cohorts born in 1900 and later exhibited higher oral cancer incidence rates than those of previous cohorts. Between the 1960s and the present, male patients 30 to 39 years of age exhibited a nearly fourfold increase in oral cancer incidence; this was not observed among similarly aged females. Connecticut counties with highest oral cancer incidence rates in both sexes were the more densely populated Hartford and New Haven counties. In general, the picture of oral cancer, as revealed through analysis of cases accessioned by the University biopsy service between 1975 and 1986, exhibited similar trends to those disclosed by analysis of CTR data. The increase in female oral cancer incidence combined with the reduced incidence in males appears to account for the dramatic decline in male-to-female ratio for oral cancer in Connecticut between 1935 and 1985. If this trend continues, the incidence of oral cancer in Connecticut women will equal that of men by the mid-1990s. © 1991.