Trends in testicular germ cell tumors among U.S. military servicemen, 1990-2003

Cancer Incidence and Etiology in the Active Duty Population of U.S. Military

INTRODUCTION

As members of the military, all active duty service members (ADS) must meet physical fitness requirements and are provided with equal-access healthcare through the DoD. In addition, 92% of ADS are ≤40 years of age. Together, these characteristics suggest that ADS represent a healthy population that may have a low risk of cancer. Each year, however, >800 ADS are diagnosed with cancer and the resulting in time off for treatment, reassignment, or medical retirement may significantly impact force readiness.

MATERIAL AND METHODS

Relevant literature was identified by searching the PubMed database using search terms ACTIVE DUTY and CANCER. Only articles written in English were included.

RESULTS

Melanoma is the most common cancer in ADS, while testicular cancer is the most common cancer in males and breast cancer is the most common in females. Cancer incidence patterns in ADS differ from those in the general U.S. population and from military veterans. Tumor etiology in ADS may be influenced by military-enriched exposures such as prolonged use of oral contraceptives, suboptimal use of sunscreen, exposure to volatile organic compounds, or germline predisposition/family history.

CONCLUSIONS

The etiology of cancer within ADS remains largely unknown. A number of new research programs may provide the means to improve understanding of the etiology of cancer in ADS. Together, these efforts will improve prevention, early detection, and clinical management, thus improving the outcomes of ADS and preserving force readiness.

Risk Factors for Testicular Cancer: Environment, Genes and Infections-Is It All?

The incidence of testicular cancer is steadily increasing over the past several decades in different developed countries. If on one side better diagnosis and treatment have shone a light on this disease, on the other side, differently from other malignant diseases, few risk factors have been identified. The reasons for the increase in testicular cancer are however unknown while risk factors are still poorly understood. Several studies have suggested that exposure to various factors in adolescence as well as in adulthood could be linked to the development of testicular cancer. Nevertheless, the role of environment, infections, and occupational exposure are undoubtedly associated with an increase or a decrease in this risk. The aim of this narrative review is to summarize the most recent evidence regarding the risk factors associated with testicular cancer, starting from the most commonly evaluated (cryptorchidism, family history, infections) to the newer identified and hypothesized risk factors.

Increase in testicular germ cell tumor incidence among Hispanic adolescents and young adults in the United States

BACKGROUND

Although rising incidence rates of testicular germ cell tumors have been well documented in white men, relatively little is known about rates in men of Hispanic origin. In the current study, the authors compared germ cell tumor trends between men of Hispanic and non-Hispanic origin as a function of age at diagnosis.

METHODS

Trends in testicular germ cell tumor incidence among white men were analyzed according to Hispanic ethnicity in 2 data sets of the National Cancer Institute's Surveillance, Epidemiology, and End Results Program, spanning from 1992 to 2010 and from 2000 to 2010 and sampling 15% and 28% of the United States population, respectively. Rates were age-adjusted to the year 2000 US standard population.

RESULTS

Between 1992 and 2010, the annual incidence of testicular germ cell tumors among Hispanic whites ages 15 to 39 years increased 58%, from 7.18 cases per 100,000 in 1992 to 11.34 cases per 100,000 by 2010 (P<1 × 10(-9) ). Their incidence rates increased in metropolitan areas for both seminoma and nonseminoma subtypes and for all stages at diagnosis. During the same 19-year interval, incidence among non-Hispanic white young adults increased 7%, from 12.41 to 13.22 per 100,000. During the 2000 to 2010 interval, no significant trends were observed in incidence among non-Hispanic whites.

CONCLUSIONS

There has been a recent substantial increase in testicular germ cell tumor incidence among Hispanic adolescents and young adults in the United States. Similar trends were not observed in non-Hispanic whites.

Adolescent and adult risk factors for testicular cancer

The incidence of testicular cancer has been increasing over the past several decades in many developed countries. The reasons for the increases are unknown because the risk factors for the disease are poorly understood. Some research suggests that in utero exposures, or those in early childhood, are likely to be important in determining an individual's level of risk. However, other research suggests that exposure to various factors in adolescence and adulthood is also linked to the development of testicular cancer. Of these, two adult occupational exposures-fire fighting and aircraft maintenance--and one environmental exposure (to organochlorine pesticides) are likely to be associated with increased risk of developing testicular cancer. By contrast, seven of the identified factors--diet, types of physical activity, military service, police work as well as exposure to ionizing radiation, electricity and acrylamide--are unlikely to increase the risk of developing testicular cancer. Finally, seven further exposures--to heat, polyvinyl chloride, nonionizing radiation, heavy metals, agricultural work, pesticides and polychlorinated biphenyls as well as marijuana use--require further study to determine their association with testicular cancer.