The incidence of colorectal cancer is rising in the younger population. In the next 15 years, more than one in ten colon cancers and nearly one in four rectal cancers will be diagnosed in patients younger than the traditional screening age. This data is of concern, especially because colorectal cancer patients younger than 40 have a worse prognosis.
There is a high prevalence of hereditary cancer syndromes in young adults and this E-Learning module provides details on colorectal cancer occurring within different hereditary syndromes.This module is part of ESMO’s activities to educate medical oncologists about the specific characteristics of cancer in young adults.
In this E-learning module, the author describes, in a very didactic way, colorectal cancer syndromes associated with polyps, in particular adenomatous polyposis syndromes (Familial Adenomatous Polyposis – FAP / Attenuated FAP, MYH-Associated Polyposis), hamartomatous polyposis syndromes (Peutz-Jeghers syndrome, juvenile polyposis syndrome, Cowden syndrome), mixed polyposis and other rare syndromes.
The author explores mutations identification in patients with adenomatous polyposis syndromes. He emphasizes that red flags identify individuals at risk for hereditary adenomatous polyposis syndromes for whom genetic counselling is warranted before proceeding with genetic testing. Furthermore, the author covers strategies for cancer risk management in adenomatous polyposis syndromes.
A further focus in the module is on Lynch syndrome (hereditary non-polyposis colorectal cancer) caused by germline mutation in one of the MMR genes. The MLH1, MSH2 are the two most commonly mutated, and the ones with the highest penetrance. The author describes clinical features and criteria for Lynch syndrome, as well as recommended Lynch screening protocol, and risk-reduction strategies for Lynch syndrome families.
The actual contribution of the known genes to the early-onset familial colorectal cancer has recently been reported. For every 5 patients with colorectal cancer, who have been diagnosed before the age of 56 and who had at least one affected first-degree relative not tested for Lynch syndrome, 1 mutation carrier is being missed, and the author challenges oncologists to consider how many patients with such characteristics they have seen during the last few years.
At the end, the author covers early onset of colorectal cancer in polymerase proofreading-associated polyposis, clinical characteristics and genetic interpretation challenges.
There is an unmet need to better understand biological characteristics or markers that make the colorectal cancer in young adults more aggressive and less responsive to treatment. Therefore, the author’s statement about how efficient we can be in cancer prevention if we identify the families at risk and act preventively either by surgeries, surveillance or chemoprevention, makes a perfect take-home message from this E-Learning module.
