predominantly in younger men, and on skin cancer, which is relatively common, are discussed in separate sections. The occurrence of cancer in veterans with PTSD is discussed at the end of the section. The primary studies for cancer are summarized in Table 6-1 at the end of the section.
The committee identified three primary studies that examined the effect of deployment to Vietnam on the development of cancer in veterans of the Vietnam War (CDC 1988b; Selected Cancers Cooperative Study Group 1990a,b,c; Watanabe and Kang 1995). Two other primary studies (Dalager et al. 1995; Kang et al. 2000c) focused exclusively on cancers in female Vietnam veterans.
In response to a congressional mandate, Centers for Disease Control and Prevention (CDC) undertook the VES to assess the health status of the 5 million Vietnam-theater and Vietnam-era veterans who served in the U.S. Army during 1965-1971; the study was completed in 1988, about 15-20 years after the war (CDC 1988b). It consisted of a nationally representative random sample of 7924 theater veterans and 7364 era veterans who completed a phase 1 telephone interview. In phase 2, a random subsample of 2490 theater veterans and 1972 era veterans also completed physical- and psychologic-health screening examinations in 1985-1986 at a medical facility. On examination, 1.9% of theater veterans and 1.3% of era veterans had cancers (unspecified); the study findings were not significant (odds ratio [OR] 1.4, 95% confidence interval [CI] includes 1.0, p > 0.05). The OR was adjusted for age at enlistment, race, year of enlistment, enlistment status, score on a general technical test, and primary military occupational specialty. The study had the advantage of including a physical examination and a large study population, but it is limited in that information on exposure to herbicides, particularly Agent Orange, was not provided, the types of cancer that were screened for were not indicated, the study was not designed to assess the presence of relatively rare cancers, and the participation rate of 75% and 63% for the theater and era veterans, respectively.
As a followup to the VES, CDC conducted a further population-based case-control assessment for six cancers in Vietnam-theater and Vietnam-era veterans: non-Hodgkin’s lymphoma (NHL), Hodgkin’s lymphoma, soft-tissue and other sarcomas, nasal cancer, nasopharyngeal cancer, and primary liver cancer. Those cancers were chosen because cancers of the liver, nasal cavity, and nasopharnyx, and Hodgkin’s disease have been associated with exposure to phenoxy herbicides, such as Agent Orange, in some animal studies and a few human studies. Study participants were all men born in 1929-1953 who were first diagnosed as having cancer in 1984-1988 and were listed in any of eight city or state cancer registries—those in Atlanta, Detroit, San Francisco, Seattle, Miami, Connecticut, Iowa, and Kansas. Controls were selected by random-digit telephone dialing in the relevant locations and frequency-matched by age to the men with cancer. All cancers were confirmed pathologically. An analysis of 1157 men with NHL and 1776 controls found that the risk of NHL in men who served in Vietnam compared with those who served in the military in 1964-1972 but not in Vietnam was 1.52 (95% CI 1.00-2.32, p = 0.01) when adjusted for registry, age group in 1968, ethnicity, education, and other covariates, including reported exposures to pesticides, reported medical history and medication use, smoking, marital status, and being raised as Jewish (Selected Cancers Cooperative Study Group 1990a). There was no suggestion of an increasing trend in risk of NHL