Newswise — Survivors of Hodgkin's lymphoma (HL), a cancer that affects the young, are at substantially increased risk of developing second cancers later in life, shows a major international study of 18,862 HL survivors.
The study evaluated cumulative risks up to 30 years after the initial diagnosis of HL and found that the incidence of all cancer types evaluated was significantly higher than normal, except for bladder and prostate cancers. Female survivors aged 40 or older who had been diagnosed with HL at age 30 had a 6-fold increase in breast cancer risk. Other forms of cancer were increased up to 20-fold. At about age 70, risks decline, but do not return to normal levels.
Lead author Dr. David Hodgson, a PMH radiation oncologist, noted that this problem was particularly dramatic for women diagnosed with HL at a young age, "We estimated that almost 25% of women diagnosed with HL at age 20 would develop a second cancer by age 50." In the general population, this rate is expected to be less than 5%, he said. The study examined the risks of colorectal and breast cancers in detail because of the possibility that screening may help detect these cancers at an early stage. In Canada, colorectal and breast cancer screening is recommended for most adults in the general population starting at age 50. "For many HL survivors, the risk of colorectal cancer in their mid-30's is comparable to that of an average 50-year-old. The risk of breast cancer in young women was also significantly elevated five to 10 years after their lymphoma diagnosis, often years before the age when routine screening would be recommended."
Says Dr. Hodgson: "The results suggest that some HL survivors should be considered for breast and colorectal cancer screening sooner than the age of routine screening."
The paper will be published online today in the Journal of Clinical Oncology, and in the print edition April 20, 2007.
Princess Margaret Hospital and its research arm, Ontario Cancer Institute, have achieved an international reputation as global leaders in the fight against cancer. Princess Margaret Hospital is a member of the University Health Network, which also includes Toronto General Hospital and Toronto Western Hospital. All three are research hospitals affiliated with the University of Toronto. For more information, go to http://www.uhn.ca