There have been "unremitting" increases in the incidence and mortality of melanoma over the past 6 decades in the state of Connecticut, according to a new analysis by public health researchers.
Incidence rates in Connecticut have increased by nearly 2000% from 1950 to 2007, while the state's population has increased by only 75% over that time, observe the authors, led by Alan Geller, PhD, of the Harvard School of Public Health in Boston, Massachusetts.
During these 6 decades, mortality rates tripled in men and doubled in women, the authors also report in their new paper, published online November 18 in the Journal of Clinical Oncology.
Connecticut was chosen as the slice of America to study because of the state's stalwart history in recording cancer cases.
The small state in the northeastern section of the country has the longest-operating population-based cancer registry in the United States, dating back to 1935. That predates by nearly 40 years the establishment of the US National Cancer Institute SEER program in 1973.
The skyrocketing incidence is not just the result of "improved reporting of melanoma," write the authors. "We are confident that the overall trends in both incidence and mortality are real," they assert in their paper.
The new results are generally the same as those found in "nearly all analyses" of melanoma trends in Europe and Australia, say the authors.
Dr. Geller and his team reviewed the state's registry and found that, in the initial study period (1950 - 1954), a diagnosis of invasive melanoma was rare, with 1.9 patient cases for men and 2.6 patient cases for women (per 100,000).
But, between the early 1950s and the study endpoint of 2007, overall incidence rates (per 100,000) rose more than 17-fold in men (1.9 to 33.5 cases) and more than 9-fold in women (2.6 to 25.3 cases)
Mortality rates also increased, but not as astronomically.
During the entire study period, mortality rates (per 100,000) rose 3-fold in men (1.6 to 4.9 deaths) and 2-fold in women (1.3 to 2.6 deaths)
There was also a shift in the median age at diagnosis — in 1950, it was 53 years in men and 52 years in women. By 2007, it was 65 years in men and 58 years in women.
The new study did have some good news: mortality rates were generally stable or decreasing in men and women aged up to 54 years.
But older men (aged > 65 years) have not stabilized and had a 6-fold increase in melanoma mortality rate over the study period. Nationally, the Institute of Medicine (IOM) has observed this trend of melanoma deaths in older guys and "recommended that physicians pay particular attention to the skin of older men." The IOM has suggested that older man ask their significant others to examine their skin, including "hard-to-see areas," periodically.
There is the possibility that some of the increased incidence rates, the authors say, may be attributable to improved registration of melanomas that would not have been recorded in earlier, less skin-conscious times. But those increases are also likely to have occurred in the diagnoses of less deadly in situ disease and thus would be unlikely to influence the undeniably higher mortality rates in Connecticut, they argue.
J Clin Oncol. 2013;31:4172-4178. Abstract