A family history of colon cancer doesn’t just put one at risk of the disease – but at risk of getting it earlier, too. Awareness of risk and regular early screening is essential to spot the cancerous enemy before it invades.

Cancer, particularly colon cancer, is a condition typically associated with older people. However, it is not unusual to see patients who are below 40 diagnosed with it. As many as 10 to 15% of all colorectal cancer cases may be these patients. Hereditary cancers such as some colorectal cancers, breast cancer and ovarian cancer, by definition, tend to occur before the age of 40 years.

Around the world, the incidence of colorectal cancers occurring in younger people seems to be rising. This is partly the result of improved diagnosis due to earlier screening that picks up the cancers earlier. Other factors which may cause this rise in young cancers include increased exposure to harmful environmental and other cancer-causing agents. Better treatments for patients with genetic cancers also mean better prognosis, with the ability to conceive and perhaps pass on the genes.

There are two main groups of patients who develop colorectal cancer at younger age. The first and most important group are those who have a family history of colorectal or associated cancers. People who are born to parents who carry gene mutations that can cause colorectal cancers have a higher risk of getting the disease than someone without a family history. There are two main groups of familial colorectal cancers. The first group, which makes up about 1-2% of all colorectal cancers, are those carrying an autosomal dominant gene called the familial adenomatous polyposis (FAP) gene. This gene causes hundreds, if not thousands, of colorectal polyps to start developing ın the colon of affected individuals ın their early teens. Some of these polyps will become cancerous before these people reach their 20s. The other sorts of genes are those seen in patients harbouring the hereditary non-polyposis colorectal cancer (HNPCC) gene. There are two sub—groups of such genes. The first only causes colorectal cancer. The second may be associated with other sorts of cancers like breast cancers, female genital tract cancers, urinary tract cancers arid endocrine gland cancers. People with these genes often develop colon cancer in their 30s or 40s.

The other group of patients who develop colorectal cancer at a younger age are those who do not have a family history of colorectal cancers, but through genetic mutation, genetic interaction between the patients’ genes, or interaction with cancer-causing substances in the environment, develop the disease. Some colorectal cancer-causing substances include azoxymethane and dimethylhydrazine, substances found in petrochemicals.

Surgery is the primary treatment of choice for colon cancer. Early-stage cancers can be treated with surgery alone, but late-stage caners may require chemotherapy and/or radiotherapy, depending on the location and stage of the cancer.

The best “treatment” however, is screening and prevention. If one has a known family history of colorectal cancer, definitive genetic testing should be performed. Alternatively, early routine colonoscopic examination should be carried out before the onset of symptoms or the appearance of cancer about 10 years earlier than the youngest affected member of the family. This will enable preventive steps to be taken to remove pre-cancerous benign polyps or detect early cancerous changes before invasive cancer sets in. Patients with a known family history and showing colorectal symptoms should be seen by a colorectal doctor immediately without delay.

It is important for patients with FAP to screen for colorectal polyps in their teens. If colonic polyps are present, surgery to remove the entire colon may needed before cancer develops. For patients in families with HNPCC, colonoscopic screening should start early, ideally 10 years before the age of the youngest affected member of the family. For instance, if an uncle developed colon cancer at age 35 and is the youngest in the family to have cancer, screening for any younger members in the family should start at 25.

This screening and early detection is essential as younger patients with colorectal cancer have a worse prognosis than older patients. The five-year survival rate for patients aged 30 or younger is about 25 to 30%. This may be because younger patients with colorectal cancers are more likely to present with late-stage disease as they are often misdiagnosed as having benign problems like irritable bowel disease and piles. Younger patients also tend to have higher grade tumours which are poorly differentiated (fast-growing and highly abnormal tissue), or mucus-filled tumours which carry a very poor prognosis. Patients under 40 with colorectal cancer often have aggressive tumours that spread quickly.

However, familial cancers are the most preventable as they are in a group that should be screened at an early stage, Furthermore, people in such families should have a wider awareness of their genetic background. Timely investigation and early treatment will ensure appropriate treatment resulting in an extremely good prognosis for such people.