Hispanics are among the fastest growing minorities in the United States, after Asian-Americans and Pacific-Islanders. Hispanics, Latinos, Chicanos, Mexican-Americans, Puerto Ricans, Cuban-Americans, etc. are all designations used to describe this large, heterogeneous population with different cultural, ethnic, geographic, and social backgrounds. There is still no clear definition of the term "Hispanic." The data available regarding the incidence, morbidity, and mortality from cancer in Hispanics are scarce, scattered, outdated, and often incomplete. From the studies looking at the accessibility and availability of medical care for this population, few have examined in detail the variability within the entire Hispanic population. The aggregation of culturally distinct subgroups, which have resided in the United States for different periods of time, into a more inclusive Hispanic category assumes that all persons of Mexican, Cuban, and Puerto Rican extraction have similar needs and experience similar barriers in using health services. There is, however, no clear evidence for this assumption. On the contrary, there is evidence that each group has specific characteristics that make it different and independent from another, despite the fact that they also share some commonalities. Because of the lower overall prevalence of cancer in this population, potential protective factors need to be explored. Hispanics, however, appear to have a less favorable stage of disease at presentation and have overall lower death rates from cancer than non-Hispanic whites, but lower overall survival in certain cancers. Demographic and epidemiologic data collection need to be updated and improved.(ABSTRACT TRUNCATED AT 250 WORDS)