Colorectal cancer (CRC) is predominantly a disease of older adults, but a concerning trend is the rising incidence among young patients under 50, while the incidence is decreasing in older adults primarily due to colonoscopy guidelines and pick up. Understanding the incidence, staging, and aetiology of colorectal cancer in the younger demographic is crucial for effective diagnosis, treatment, and prevention.
Over the past few decades, the incidence of colorectal cancer in young patients has seen a notable increase. Recent statistics reveal a 1-2% annual rise in CRC cases among individuals aged 20-49. This demographic now accounts for about 1 in 10 colon cancers in Australia. Our own database in the Western Australian St John of God Health Care group would suggest the same and more of an increase in the past three years with an average of 13.7% of our cohort being less than 50 at the time of diagnosis.
Several factors contribute to this upward trend, and it is still not fully understood. Increased awareness and improved diagnostic techniques are crucial for earlier and more frequent detection. However, lifestyle factors such as sedentary behaviour, poor diet, obesity, and smoking are also significant contributors. Studies suggest that the rising prevalence of these risk factors among young people parallels the increased incidence of CRC in this group.
Unfortunately, diagnostic protocols are targeted to older patients with age becoming a bias. Being younger means not being routinely screened for CRC, patients have delayed access to investigations such as colonoscopy often with multiple visits to general practitioners and specialists.
As expected, delay in diagnosis means more advanced stage at diagnosis. There is some evidence that younger patients often present with stage III and IV cancer with more aggressive disease characteristics.
Stage IV colorectal cancer in young individuals involves distant metastasis to organs such as the liver or lungs. Young patients often face a more aggressive disease course with a higher likelihood of multiple metastatic sites. Treatment usually involves a combination of surgery, chemotherapy, targeted therapy, and sometimes immunotherapy.
Despite the aggressive nature of the disease, younger patients often respond better to treatment, showing longer survival times compared to older patients, but the overall five-year survival rate remains low at around 14%.
The following recurring symptoms should be immediate red flags, with increased risks with more than one symptom: abdominal pain, rectal bleeding, change in bowel habit, usually diarrhoea and deficiency anaemia.
However, some of these symptoms can be attributed to irritable bowel syndrome (IBS), which is quite prevalent in young adults making it more challenging to identify those patients who need to proceed to colonoscopy. It is certainly useful for patients to be familiar with the importance of those symptoms. The incidence of rectal cancer incidence also seems to be on the rise and a rectal examination will help identify a low rectal mass.
Bowel Cancer Australia recommends Faecal Occult Blood Test every two years from the age of 45 in asymptomatic patients. From July 1, the National Bowel Cancer Screening Program (NBCSP) has also made that age group eligible for testing. The test can be offered to ‘concerned’ or ‘concerning’ patients aged 40-44.
Ultimately, the rise in colorectal cancer in young patients means a thorough history taking in particular of the personal and family history of cancer and polyps will help determine the risk of each patient, hence guiding the referral for investigations.
Genetic counselling and testing of young patients with colorectal cancer can further identify at risk patients and family members. Moreover, there is good evidence (level 1) that starting low dose aspirin in those high risks patients can reduce incidence and death from CRC. Young adults’ colorectal cancer diagnosis also brings on new challenges such as oncofertility and discussing fertility status and options for parenthood after cancer is important.
The rising incidence of colorectal cancer in young patients is a pressing public health concern. CRC is already the second most common cancer and the second most common cause of cancer deaths in Australia. The NHMR has clear recommendations for prevention, early detection and management of CRC. Younger patients require a higher level of scrutiny and careful and timely follow-up of symptoms.
Key messages
- The rising incidence of colorectal cancer in young patients is a pressing public health concern
- Colorectal cancer is already the second most common cancer and the second most common cause of cancer deaths in Australia
- Younger patients require higher level of scrutiny and more careful and timelier follow-up of symptoms.
– References available on request
Author competing interests – nil