Survivors of childhood Wilms tumor (WT) and Hodgkin lymphoma (HL) have a risk of colorectal cancer comparable to that of individuals with a strong family history of the disease, new findings show. "The findings suggest that survivors of a childhood Wilms tumour or Hodgkin lymphoma are at risk of developing colorectal cancer and that this risk is as high as for individuals from the general population who have at least two first-degree relatives affected by colorectal cancer before age 55," said Dr. Raoul C. Reulen of the University of Birmingham College of Medical and Dental Sciences in Birmingham, UK, the study's senior author. "In many countries colonoscopy surveillance is recommended for the latter group," he told Reuters Health in an email. "This begs the question whether childhood cancer survivors at similar risk should also be offered colonoscopy surveillance, if not already." Childhood-cancer survivors are known to be at risk of subsequent primary neoplasms (SPNs). To investigate whether they face an excess risk of digestive cancers after age 40 compared to the general population, Dr. Reulen and his team looked the PanCareSurFup cohort, which includes more than 69,000 five-year childhood-cancer survivors from 12 European countries. A total of 427 digestive SPNs were diagnosed in 413 survivors, including 214 colorectal tumors, 62 liver tumors, 48 stomach tumors, 44 pancreas tumors and 59 others. The risk of any digestive SPN was more than three times as high as would be expected in the general population, the researchers report in Gut. WT survivors had the highest risk of SPNs overall (standardized incidence ratio, 12.1), followed by HT survivors (SIR, 7.3), both significant risk increases. They also had the sharpest increase in cumulative SPN incidence with age, from 7.4% at 55 to 9.6% by 60. Colorectal SPNs had developed in 2.3% of WT and HL survivors by age 55, which the authors note is similar to the risk conferred by having two first-degree relatives with the disease. "As part of the PanCareSurFup study, we have collected more detailed data on radiotherapy and chemotherapy on a subset of the current cohort study. We are currently analysing the data from this study and should be able to address the risks of developing colorectal SPNs at the lower end of the radiation-dose spectrum and influence of different types of chemotherapy exposures," Dr. Reulen said. Next steps should also include "studies evaluating the benefits, harms, cost-effectiveness and most appropriate method of colorectal cancer surveillance," he said. "Together with expert colleagues around the world we are currently looking at all available evidence relevant to colorectal cancer surveillance in survivors of childhood, adolescent and young adult cancer with the aim of developing international guidelines. More information: www.ighg.org," he concluded. —Anne Harding Source