Elevated cancer risk in Holocaust survivors

Holocaust survivors were exposed to a variety of factors that have been linked with cancer. Siegal Sadetzki, MD, MPH, of the Chaim Sheba Medical Center in Israel, and her colleagues wondered whether the starvation, overcrowding, infectious diseases, and psychological stress that survivors endured might have contributed to the development of cancer in some individuals.

To investigate, the team studied 152,622 Holocaust survivors who were followed for more than 45 years. Two separate definitions of exposure were used. One definition was based on the individual's entitlement for compensation according to a set of laws. The other was based on the country of origin, using a classification of countries during the war into those that were directly governed by Nazi Germany and other non-occupied countries.

Cancer was diagnosed in 22 percent of those who were granted compensation for suffering persecution during the war versus 16 percent of those who were denied compensation. Survivors who were granted compensation had a six percent higher risk of developing any type of cancer than those who were denied compensation, and they had a 12 percent increased risk for colorectal cancer and a 37 percent increased risk for lung cancer. Those born in occupied countries had an eight percent increased risk of developing any cancer than those born in non-occupied countries, as well as eight percent and 12 percent increased risks of colorectal cancer and lung cancer, respectively. The investigators observed no elevated risks for breast cancer and gynecologic cancers among female survivors.

"The data emphasize the importance of learning about the combined effect of several exposures occurring intensely and contemporaneously on cancer risk, such as those that unfortunately occurred during World War II," said Prof. Sadetzki. "Such inspection cannot be conducted by experimental studies and could only be evaluated by using observational epidemiological surveys."

An accompanying editorial notes that the associations reported by Prof. Sadetzki and colleagues between the extreme deprivation experienced by Holocaust survivors and cancer may also have parallels with other extreme population-level events, including in racial/ethnic minority groups who experience severe social deprivation over time.