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BACKGROUND Recent reports have suggested that the increasing rates of testicular germ cell tumors in some populations have begun to plateau. This study was conducted to examine whether rates among white men in the United States have begun to stabilize and whether rates among black men in the United States have remained low. METHODS Testicular germ cell tumor incidence data from in the Surveillance, Epidemiology, and End Results Program were analyzed for the years 1973–1998. Trends were examined separately for seminoma and nonseminoma. Using age‐period‐cohort analyses with 5‐year age intervals and 5‐year calendar‐period intervals, changes in the slope of the trends in birth‐cohort and calendar‐period effects were examined. RESULTS Among white men, rates of seminoma continued to increase, but the rate of increase steadily declined throughout the 26‐year time span. Nonseminoma rates among whites increased more slowly during the first three time intervals, then plateaued in the final interval. Rates of both seminoma and nonseminoma in black men fluctuated throughout the first three time intervals. In the final interval, the rates of seminoma increased almost 100%, whereas the rates of nonseminoma increased more modestly. Age‐period‐cohort modeling of the incidence data in white men found that, whereas the dominant effect was that of birth cohort, there also was a period effect. CONCLUSIONS Among white men in the United States, the incidence of testicular germ cell tumors varied by histology, with a continuing increase in risk only for seminoma. Among black men in the United States, the surprising increases seen between 1988 and 1998 were likely to be a calendar‐period effect. Cancer 2003;97:63–70. Published 2003 by the American Cancer Society. DOI 10.1002/cncr.11054

Primary liver cancer (PLC) is common in many areas of the developing world, but uncommon in most of the developed world. Some evidence suggests, however, that the global pattern of PLC may be changing. To clarify this issue, we examined incidence rates for PLC over the 15-year time period, 1978 -92, in selected cancer registries around the world. With some exceptions, developed countries have experienced PLC increases in incidence whereas developing countries have experienced declines. Although the reasons for the trends are not entirely clear, the increased seroprevalence of HCV in the developed world and the elimination of HBV-cofactors in the developing world are likely to have contributed to the patterns. Further progress against PLC may be seen in the developing world once the HBV-vaccinated segment of the population reaches adulthood. Primary liver cancer (PLC) is the fifth most common cancer in the world 1 and the fourth most common cause of cancer mortality. 2 PLC is composed of several subtypes, including hepatocellular carcinoma, cholangiocarcinoma, hepatoblastoma, and angiosarcoma. In most countries, hepatocellular carcinoma comprises 85-90% of PLC and so the terms are often used interchangeably.PLC rates have an extremely wide geographic variation, such that 80% of the cases arise in developing countries, particularly those of southeast Asia and sub-Saharan Africa. Even within a confined geographic area, certain ethnic groups have higher PLC rates than others. In these high-rate populations, chronic infection with hepatitis B virus (HBV), and contamination of foodstuffs with aflatoxin B1 (AFB1) are recognized major risk factors. In contrast, neither HBV nor AFB1 is considered to be a major factor in low-rate areas of the developed world. Alcohol ingestion and, increasingly, hepatitis C virus (HCV) infection are more likely to be related to PLC in these areas. Reports of incidence rates declining in some high-risk populations 3 while increasing in some low-risk populations 4 -6 suggest that the global patterns of liver cancer may be changing. To determine whether the reported changes are isolated phenomena or whether new global patterns of liver cancer are emerging, we examined incidence trends over the 15-year period 1978 -92. MATERIAL AND METHODS Incidence dataTo examine the current global pattern of PLC incidence, genderspecific rates in 53 registries were abstracted for 67 populations by Parkin et al. 7 An effort was made to include registries from each continent and registries that reported data for more than 1 ethnic group, but no more than 1 registry from any single country was included. To examine the trends over time, gender and age-specific and -standardized incidence rates in 23 populations from 21 registries were retrieved by The abstracted rates cover 3 5-year intervals : 1978 -82, 1983-87 and 1988 -92 and are age-adjusted to the world standard population. Use of a fourth time period (1973-77) was considered but rejected due to its use of the International Classification of Diseases, ...

Prostate cancer is the most commonly diagnosed cancer in western men, and incidence is rising rapidly in most countries, including low-risk populations. Age-adjusted incidence and mortality rates from 15 and 13 countries between 1973-77 and 1988-92, respectively, were compared to provide leads for future analytic studies. Large increases in both incidence and mortality rates of prostate cancer were seen for all countries. For incidence, increases were more pronounced in the United States, Canada, Australia, France and the Asian countries, while the increases in medium-risk countries were moderate. Increases in incidence ranged from 25%-114%, 24%-55% and 15%-104% in high-, medium-and low-risk countries, respectively. Mortality rates rose more rapidly in Asian countries than in high-risk countries. Substantial differences in incidence and mortality across countries were evident, with U.S. blacks having rates that were 50-60 times higher than the rates in Shanghai, China. Increasing incidence rates in the United States and Canada are likely to be due in part to the widespread use of transurethral resection of the prostate and prostate-specific antigen testing, while increases in the Asian countries are probably related to westernization in these low-risk populations. The large disparities in incidence between high-and low-risk countries may be due to a combination of genetic and environmental factors. Prostate cancer is the most commonly diagnosed cancer among men in most western countries (Parkin et al., 1997). With the aging of the population and increased prostate cancer screening, especially the use of prostate-specific antigen (PSA), the incidence of prostate cancer in the United States and certain western countries has risen sharply during the last decade (Potosky et al., 1995;Mercer et al., 1997;Majeed and Burgess, 1994;Weller et al., 1998). In the United States, the rapid increase in incidence since the introduction of PSA in 1986 has resulted in a lower median age at diagnosis (decreased by 1 year in both blacks and whites) and an earlier stage of cancer at diagnosis, although the benefit of screening on prostate cancer mortality rates remains undetermined (Prorok et al., 1996). Prostate cancer rates in Asian countries, such as China and Japan, are much lower than those reported in western populations (U.S. rates are 50-60 times higher), but they appear to be increasing rapidly as well (Nakata et al., 1995;Hsing et al., 1998). In this report, we examine trends and patterns of incidence and mortality during a 20-year period (from 1973-77 to 1988-92) in more than a dozen countries to provide clues for future studies. MATERIAL AND METHODS Incidence dataWe retrieved age-specific and standardized incidence rates per 100,000 man-years, age-adjusted to the world standard, for prostate cancer during the 20-year period (1973-77 to 1988-92) in 15 countries from 4 volumes (IV-VII) of publications from the International Agency for Research on Cancer (IARC), Cancer Incidence in 5 Continents, covering the time periods ...