Colorectal Cancer Screening and the Pediatric Subspecialist

Colorectal Cancer Screening and the Pediatric Subspecialist 150 150 Katie Brind'Amour, PhD, MS, CHES

Screening a 15-year-old for pre-cancerous polyps may seem a bit unusual, as colon cancer is widely considered an adult disease. But for children with a family history of Lynch syndrome, a hereditary condition that increases the risk of colon and other cancers, life-threatening malignancies can develop as early as the mid-teens. Fewer than one in every four children diagnosed with colorectal cancer survive, so early diagnosis is crucial.

That is why Steve Erdman, MD, is looking for clues in family history and trying to spread the word to other pediatric subspecialists about the importance of appropriate surveillance. Although colorectal cancer is rare in childhood, it is the most common pediatric intestinal tract primary malignant solid tumor. About three percent of all cases of the disease occur in patients with Lynch syndrome, and in some of these families each generation seems to develop malignancies earlier than the one before. Due to the potential for disease onset in adolescence, this surveillance and screening should begin as early as age 10 in some families.

“Surveillance in Lynch syndrome has been proven to be cost-effective and can prevent devastating complications,” says Dr. Erdman, a pediatric gastroenterologist at Nationwide Children’s Hospital and author of a recent review on pediatric Lynch syndrome published in the Journal of Pediatric Gastroenterology and Nutrition. “Genetic testing can identify families that would greatly benefit from surveillance and those within a high-risk family who can forgo early screening.”

Lynch syndrome is caused by a mutation in one of four specific genes involved in DNA mismatch repair. Children who inherit a mutation have a lifetime risk of developing colorectal cancer of nearly 70 percent and a risk of related diseases, such as endometrial cancer, approaching 40 percent. Although colorectal cancer is the most likely Lynch-related cancer to manifest in adolescence, individuals with the syndrome also have a much higher likelihood of developing digestive and urologic cancers in their 20s and 30s.

Lifelong follow-up is essential for people with Lynch syndrome, as the condition also results in faster cancer progression: adenomas progress to carcinomas in just one to two years versus the standard timeframe of eight to 10 years for sporadic or other hereditary conditions.

Identifying families at risk for Lynch syndrome is as simple as remembering a 3-2-1 rule of thumb, Dr. Erdman says.

  • Three or more affected family members have been diagnosed with colon or another Lynch-type cancer (endometrial, stomach, ovarian, pancreatic or renal).
  • Two successive generations have been diagnosed with cancer.
  • One family member must have been diagnosed with cancer before the age of 50.

These three key requirements are the basis of the Amsterdam Criteria, the classic diagnostic criteria that help identify families at risk for Lynch syndrome and who should be referred for genetic counseling and testing.

Although Lynch-type cancers are rare in adolescents, the syndrome is a common familial condition that can be identified by a careful family history, allowing for early referral for diagnosis and initiation of cancer surveillance for those that will benefit. Knowing the family risk factors, testing for Lynch syndrome and using the results as a preventative tool could prevent cancer and save lives, according to Dr. Erdman. But it requires awareness and long-term involvement on the part of primary care providers and subspecialists alike to make it happen, he says.

“Any family that has lost a parent from colorectal cancer under the age of 40 or that has multiple family members with cancer diagnoses or deaths should be referred for genetic counseling and testing,” Dr. Erdman says. “Many families want to know what they are facing and are relieved to learn that, through careful surveillance and monitoring, they can control the cancer risks that have impacted their affected relatives. The importance of subspecialists’ role in identifying these children and ensuring they receive the testing and monitoring they need cannot be underestimated.”

Huang SC, Durno CA, Erdman SH. Lynch syndrome: a pediatric perspectiveJournal of Pediatric Gastroenterology and Nutrition. 2014 Feb, 58(2):146-54.

About the author

Katherine (Katie) Brind’Amour is a freelance medical and health science writer based in Pennsylvania. She has written about nearly every therapeutic area for patients, doctors and the general public. Dr. Brind’Amour specializes in health literacy and patient education. She completed her BS and MS degrees in Biology at Arizona State University and her PhD in Health Services Management and Policy at The Ohio State University. She is a Certified Health Education Specialist and is interested in health promotion via health programs and the communication of medical information.