Colon Cancer

Medical Grapevine Magazine Medical Contributions by Dr Ganesh Ramalingam – March 2016

Why colon cancer patients are getting younger

Regular exercise and food low in fat and high in fibre: this is the mantra of the Centre for Weight Loss and Metabolic Surgery in PanAsia Surgery. These are vital ingredients that are missing in the lives of young adults today and surprisingly, these are exactly the postulated causes of an alarming rise in colorectal cancer rates among young adults aged 25 to 40.

In general, about 90% of colorectal cancer is discovered in patients over the age of 50. The exact cause of this disease is yet to be identified, but age is a significant risk factor in the development of this disease. Traditionally, it is rare to have colorectal cancer in the young adult, with the main cause in people in the 30s and 40s being hereditary. These inherited disorders, such as familial adenomatous polyposis and Lynch syndrome (HNPCC or hereditary nonpolyposis colorectal cancer), are rare, but they increase the risk of colon cancer.

Risk factors

Furthermore, anyone, regardless of age, has an increased likelihood of developing colon cancer if a parent, sibling or child has the disease. Other risk factors would include inflammatory bowel disease (IBD – namely ulcerative colitis and Crohn’s disease), smoking, heavy alcohol consumption and diabetes. Added a sedentary lifestyle and this list a high fat, low fibre diet.

There is growing evidence around the world, through studies of the occurrence of this disease, showing that colon cancers are occurring at increasing rates in people younger than 50. They indicate that younger people account for more than 10% of all colorectal cancers. There is a report from Australia that has mentioned that in the last 20 years, the incidence of colorectal cancer in the age group of 20 to 34 has risen by almost 65% in the last 20 years. The common list of causes for young patients is environmental factors, changes in diet and lifestyle and a worldwide trend toward obesity, contributing to this rise.

Symptoms not to be ignored

Symptoms, or presentation of complaints to doctors, are similar in people of all ages. The common symptoms, or the reason why people afflicted with colorectal cancer first see a doctor, are bleeding through the rectum and lower abdominal discomfort. Other presentations would include a change in the calibre of stool, constipation diarrhoea or weight loss. Blood investigations indicating new onset anemia, low hemoglobin levels, and tumour markers like CEA (carcinoembryonic antigen) give an indication of the potential presence of a colorectal tumour. Unfortunately, statistics show that the disease is commonly detected at a more advanced stage in younger people mainly because it is not usually suspected in this age group.

A young person with “the usual lower tummy ache once in a while and just given some painkillers and a medical certificate from work” or “I have seen a few doctors for bleeding after going to the toilet and was told I have piles’ has increasingly heralded something more sinister. These complaints should not be dismissed without proper investigations to conclusively prove the diagnosis. It is strongly advised that anyone, regardless of age, experiencing symptoms of colorectal cancer, especially bleeding while in the toilet and lower abdominal discomfort that is recurrent, seek a doctor for further advice and investigation Timely screening for people at high risk for colon cancer, along with a prompt assessment of any worrisome symptoms, is vital for diagnosing colorectal cancer at an earlier stage and for successful colon cancer treatment.

Screening saves lives

There are numerous clinical studies that prove that screening does save lives. Statistics from many centres in the United States, Europe and Asia show significant benefits in colorectal screening and early investigation for people with symptoms. In the Ministry of Health (MOH) of Singapore colorectal cancer screening guidelines, it is strongly recommended for anyone over the age of 50 years to undergo a screening test.

The best way in which colorectal cancer screening can be undertaken is a flexible colonoscopy in terms of accuracy, safety and tissue sampling as compared to fecal occult blood test which is used as a simple screening tool for the general population. Other methods would include CT colonography, barium enema and sampling of stool for DNA. However, these other methods are not proven. Since most colorectal cancers occur in the older age group, routine screening typically does not begin until age 50. For those with genetic risk factors, a family history of colon cancer, or other significant risk factors, screening is recommended at a decade earlier at age 40 or even in the mid-20s if the risk is very high.

Once colorectal cancer is diagnosed, the tumour will then be staged by a traditional classification known as the Dukes’ staging. This is required as it gives an indication of the prognosis, or the “severity” of the disease, and treatments are most appropriate. A CT scan is then done to see if the cancer has spread to other organs, such as the liver or  the lungs. Subsequently, there will be a team of specialists including doctors, nurses, radiologists, oncologists, radiotherapists who will review all the test results and the holistic overview of the patient. With all this in mind, a schedule of suitable treatment, which may include surgery, chemotherapy and radiotherapy and other treatments, will be recommended.

Treatment options available

The best hope at this point in time for the cure of colorectal cancer is surgery and if the disease is detected at an earlier stage, the chances of successfully managing it increases. Essentially, the section of the bowel that contains the cancer is removed or resected, and the two open ends are anastomosed or joined back together. This is potentially a cure for early cancers which are confined to the bowel wall and not spread.

However, there are situations that the bowel ends are not suitable to be joined, commonly due to the fact that the tumour is too low down in the pelvis, the upper end of the bowel can be brought out through the abdominal wall. Thus, faeces coming through the bowel opening, or stoma, will be collected in a bag, also known as a colostomy bag. The stoma may either be permanent or temporary depending on the condition of the patient or the nature of cancer. There are situations when the disease is detected late, either due to late presentation of symptoms or delayed investigation of the symptoms, and cancer has spread to other parts of the body.

This is known as metastatic deposits and these cells will grow into secondary cancer islands and will need further systemic treatment. This is the highest stage, or stage 4, of colorectal cancer.

In addition to surgery, chemotherapy and, in some cases depending on the type and location of cancer, radiotherapy are also used to treat colorectal cancer together with surgery, especially if the tumours are at a higher stage when first detected. Chemotherapy is generally used in colon cancer treatment and a combination of radiotherapy and chemotherapy is sometimes indicated for rectal cancer. If the tumour is very large, these therapies may be used before surgery. It is then known as neoadjuvant therapy to reduce the size of the cancer. There is evidence that it reduces the risk of cancer recurrence and improves survival rates, or the length of time patients live after treatment. More commonly, chemotherapy may be used after surgery to eliminate cancer cells that potentially has spread, especially if the tumour is beyond the earliest stages. This is called “adjuvant” chemotherapy. There are numerous types of chemotherapy drugs of different effects and side effects, and many studies are being conducted to define the most effective combinations for treatment.

There are other new treatment modalities like biological therapy (they rely on the body’s natural immune system and chemicals) that are being researched and tested on for patients with colorectal cancer.

Key to treatment success

The key aspect on the success of treatment for the patient with colorectal cancer depends largely on the stage cancer has reached before first detection and start of treatment. Statistics show that the duration of time patients with colorectal cancer has risen significantly over the last quarter of a century. However, despite these favourable numbers, only about half the number of people diagnosed with colorectal cancer actually live 5 years after diagnosis. This is explained in part by the fact that many of these patients are elderly and a number of them perish due to other health reasons.

What, then, can be done to improve these numbers, especially for the younger population? Reviewing the facts, the only certainty is that when colorectal cancers are found in an earlier stage, especially stage 1 and 2, the success of surgery with or without other additional modalities, a very high, approaching full cure. After stage 2, the success of treatment and duration of survival drops precipitously. And as compared to the elderly, patients between the age of 25 to 40 have cancers that are detected at a later stage.

A change of lifestyle is extremely important. There must be plenty of fibre in the diet which includes generous portions of fruit and vegetable. This high-fibre diet can be augmented with whole or multi-grain carbohydrates like bread and unpolished rice. The amount of red meat has to be reduced and without a doubt, saturated fat intake has to be brought to a minimum.

Exercise plays a huge role in prevention as well. Regular cardiovascular exercise is protective against colorectal cancer in a few ways. It reduces stress, improves bowel movement and more significantly, reduce obesity. Obesity is a known risk factor for colorectal cancer, and it is well known that the young people of today have high rates of obesity and are brought up on high fat and red meat diet.

Excessive alcohol consumption and an increasing number of young people both male and female who smoke heavily are further contributory factors and there must be increased awareness and legislation to reduce these bad habits and stop youngsters from even starting.

The power of raising awareness

There has to be an increased awareness of the alarm symptoms of colorectal cancer. A family history of colorectal cancer, especially if the person afflicted is young, bleeding around the time of bowel movements, lower abdominal discomfort, constipation, a sensation of a lump in the tummy and loss of weight have to be thoroughly investigated. And they should be investigated, regardless of the age of the person who has it. It is s strongly recommended that a colonoscopy is the modality of choice for investigation and diagnosis. Small growths along the wall of the colon called polyps are easily detected and removed via the colonoscope.

Polyps may be the earliest manifestation of colorectal cancers, and it has been shown that up to 30% of people with the polyps have an increased chance of acquiring colorectal cancer. When colorectal cancer occurs outside families who have the genetic trait, is called sporadic colorectal cancer. In the past, for it to occur, was a very rare event. However, as mentioned, the incidence of sporadic colorectal cancers in the young is rising. We also are aware that the children of those who develop colorectal cancer at a young age, are at a higher risk for early colon cancers themselves and need to do colon cancer treatment as soon as possible. It is therefore important to reveal to the doctor looking after you, the age at which any family member or relative discovered their first polyp or cancer.

Although very rare in Singapore, when a family is known to have is Familial adenomatous polyposis (FAP), each child has a 50% chance of inheriting the gene that will lead to multiple polyps in the colon by the time they are in their mid-teens. If this happens, literally all these patients will get colorectal cancer just after the age of 30. The recommendation is that the affected parent and at risk children be screened with a genetic test and have genetic counselling done. Children who have the genes start having colonoscopic surveillance an about 10 to 12 years old and subsequently every six to 12 months to look for polyps. Once numerous poly is found, surgery to remove the whole colon is scheduled.

Unlike FAP the other inherited disorder, hereditary non-polyposis colorectal cancer (HNPCC), has fewer polyps seen on colonoscopy, and they present at a later age. For this disorder, the recommendation is colonoscopy for young adults at risk, from age 25 and repeated every two years. Despite the differences, the risk of developing cancer from this syndrome is also very high. The entire family has to participate in genetic counselling and testing services are available.

Conclusion

For those who have been diagnosed with colorectal cancer, the good news is that the surgical options include a method whereby the colon can often be removed by a “keyhole” or laparoscopic approach. There will be faster recovery from the surgery and less severe wound complications. The care of patients before and after surgery as well as the vast improvements in anaesthesia and operative technology has made this major surgery much safer and more effective. Advances in radiotherapy and chemotherapy have broadened the options and again improved the safety profile of these treatments. Furthermore, patients aged below 50, despite increasingly being diagnosed with advanced cancer, have fairly comparable survival rates as their youth and fitness can better withstand the treatment.

The mantra simply has to be: prevention better than cure and early detection and treatment is the recommended gold standard for colorectal cancers in everyone, especially the younger patients.

More info: Colonoscopy and Colorectal topics