LOS ANGELES (CNS) — In what is billed as a first study of its kind, USC researchers announced on Monday, Dec. 14, that they have found that colorectal cancer risk in Latinos throughout California varies widely depending on their nation of origin.

Latinos are the largest and fastest growing minority ethnic group in America. Some 14.7 million Latinos living in California represent 38.4 percent of the state’s population and 27 percent of the entire U.S. Latino population, according to the U.S. Census Bureau.

“Hispanics are a very heterogeneous population, which is not really recognized in most cancer studies,” said lead author Mariana Stern, a cancer epidemiologist and associate professor of preventive medicine at the Keck School of Medicine of USC.

“Their risk factors might be different; their clinical characteristics could be different. We have to zoom into these observations and understand these disparities because they may affect how patients are educated about the disease and how they are treated by doctors.”

Using California Cancer Registry data, USC researchers examined the profiles of 36,133 Latinos and 174,710 whites who were diagnosed with colorectal cancer between 1995 and 2011.

Latinos were further identified by their country, region or commonwealth of origin: Mexico, Cuba, Puerto Rico, Central or South America, or not specified. USC researchers hope to use the study to pave the road toward personalized cancer care.

Here are the specific findings:

       — Latinos from Mexico have the lowest chance of getting colorectal cancer when compared to other Latino subgroups;

       — More Mexicans — 20 percent — and Central or South Americans — 20 percent — were diagnosed with colorectal cancer before age 50 compared to

other Latino subgroups;

      — Among Latinos in California, Cuban colorectal cancer patients had the highest proportion of deaths — 63 percent — followed by Puerto Ricans — 58

percent; and

      — Mexicans had a higher percentage of rectal cancer — 35 percent — than other Latino subgroups.

“We have pioneered surveillance of ethnic differences in cancer risk,” said senior author Lihua Liu, assistant professor of clinical preventive medicine at Keck Medicine of USC and a research scientist in the Los Angeles Cancer Surveillance Program.

“We have previously shown dramatic differences in cancer risk among Asian subgroups.”

She added, “It’s time to also examine the heterogeneity within Latinos.”