Surgical Conditions

Liver Cancer  ::  Bowel Cancer

Bowel Cancer

What is bowel cancer?

Bowel cancer is one of the most common solid tumours in the Western world. It is also known as Colorectal Cancer. Malignant cells may arise in the colon or the rectum and these may develop into a tumour resulting in symptoms such as rectal bleeding or an alteration in bowel habit. If untreated, this cancer will spread to other parts of the body and may ultimately be fatal.

Colorectal cancer is responsible for a large number of cancer deaths in Australia each year. In 2006, there were almost 5,000 new cases of bowel cancer diagnosed in NSW alone, and approximately 1,700 patients died of this disease despite treatment. Males and females are affected in almost equal proportion and overall it is the second most common cancer in our community. Colorectal cancer ranks in incidence just after prostate cancer in males and breast cancer in females. By 85 years of age, approximately 1 in 10 males and 1 in 14 females will develop bowel cancer and, over the past 10 years, these incidence rates have not changed significantly. Despite the persistent incidence of this disease, there has been a fall in the overall mortality rate by approximately 20% in both males and females.

What are the risk factors for Colorectal Cancer?

Colorectal cancer can occur sporadically but there are also several well-recognised risk factors. These include being over the age of 50, having a family history of bowel cancer, having a personal history of bowel polyps or inflammatory bowel disease, being overweight, consuming a diet high in animal fats and red or processed meats, living a sedentary lifestyle or consuming a large amount of tobacco or alcohol.

How is Colorectal Cancer diagnosed?

Patients may present with a persistent alteration in their bowel habit or blood or mucous mixed in with their stools. Occasionally, patients present with complications due to obstruction of the colon or rectum by the tumour. This may cause persistent, cramping, abdominal pain and gross abdominal distension. Very rarely, bowel cancers may even perforate (burst) and this leads to a surgical emergency. With the increasing use of screening tests (blood in the stools or tumour marker blood tests or colonoscopy) patients are being diagnosed earlier. Unfortunately, bowel cancer can be present for a long period of time without causing major symptoms. In this case, patients will present with an advanced cancer that may be difficult to treat. Cancer cells can spread beyond the bowel wall and into distant sites such as the lymph glands or the liver or the lungs. This is known as “metastatic cancer”. Distant metastases (liver or lung) used to be associated with a very poor prognosis but there have been significant improvements in the treatment of this disease over the past decade and excellent results can now be achieved with modern combination treatments. Cancers that have spread to the liver are known as “liver metastases”. These tumours are best detected by an abdominal CT scan or a magnetic resonance scan.

What are the treatment options for patients with Colorectal Cancer?

The treatment depends on the stage of the disease when the patient first presents. If there is a primary bowel cancer only (ie. a tumour confined to the bowel) then the main treatment option is an operation to remove the tumour. This is performed by a “General” or “Colorectal surgeon” and the ultimate long term prognosis depends on how far the tumour has spread into the local lymph glands. Modern chemotherapy agents specifically target colorectal cancer and these have been extremely effective in helping treat this disease. Patients with localised bowel tumours but with spread to the lymph glands may receive chemotherapy or radiotherapy before or after their surgery with the aim of helping to cure the disease by reducing the risk of cancer recurrence. If patients have liver metastases at first presentation, in addition to their bowel cancer, then they are usually offered chemotherapy after the bowel surgery. Some centres may even offer surgery to remove the liver tumours first as long as there are no other signs of spread of the disease.

The Northern Upper GI Surgical Unit specialises in the treatment of patients with Colorectal Liver Metastases.  The two surgeons, Dr Tom Hugh and Dr Jas Samra have been specifically trained as surgical oncologists and they work in a large multidisciplinary team.

Dr. Thomas J Hugh MD, FRACS

The Unit also consists of a dedicated Cancer Nurse Coordinator, a Hepato-Biliary Surgical Fellow, two general surgical registrars, experienced operating room and ward nurses, two resident medical officers, administrative support and a full time data manager.  Dr Hugh and A/Prof. Samra teach surgical trainees regularly and they also undertake clinical research in the field of liver cancer.  Both surgeons are executive board members of a cancer research group called “CanSur”. This is based in the Kolling Research Building on the RNSH campus.  Dr Hugh and A/Prof. Samra are involved in numerous clinical research projects specifically in the field of colorectal liver metastases.  As part of this research, the HPB Unit has created a large tumour tissue “bank” where a small sample of each patient’s tumour and a piece of normal liver are separately collected and snap frozen for later research analysis.  These specimens provide a unique and valuable opportunity to analyse the potential causes and biomarkers of this cancer.

What is the prognosis following a diagnosis of Colorectal Cancer?

In patients with cancer confined to the bowel and who undergo an operation, the overall chances of cure are approximately 55%. About 20% of all patients with bowel cancer present with liver metastases and a further 20% will develop liver metastases at a later stage. Many of these patients are suitable for surgery to remove their liver tumours. In patients with isolated liver metastases and who undergo complete resection, approximately 50% will be cured of their disease. This is a dramatic improvement in survival outcome over the past 20 years compared with the past.

Can this disease ever be totally cured in Australia?

Reducing known risk factors for colorectal cancer is the most important preventative measure that will reduce the incidence of this disease. This includes increasing physical activity and consuming a diet rich in fruit and vegetables, cereals and wholegrains and minimising the consumption of tobacco and alcohol. Screening high risk patient groups is likely to pick up early disease and it is anticipated that this will also reduce the death rate. Bowel screening is now common practice for at-risk groups in Australia. This involves second yearly testing of stools for occult blood and, if positive, subsequently undergoing a colonoscopy (a telescope examination of the bowel). A large amount of research into colorectal cancer is occurring worldwide and there are encouraging signs that breakthroughs in treatment will soon be available.

The Hepato-Biliary surgeons in the Northern Upper GI Surgical Unit (Dr Hugh and A/Prof. Samra) are very interested in research that might identify factors within tumour tissue or within patients’ blood that will predict the presence of malignant cells. The hope is that this will lead to a screening test that will pick up disease at an early stage and lead to a greater chance of cure. If such a screening test could be developed this would have a significant impact on reducing the incidence of death from colorectal cancer.

How can you support Colorectal Cancer research in the Northern Sydney area?

By making a donation to the research foundation associated with the Northern Upper GI Surgical Unit. The ultimate aim of this foundation is to establish a full-time cancer research scientist within the CanSur laboratories in the Kolling Building so that the surgeons can work closely with this individual to undertake laboratory-based cancer research. It is likely that significant treatment breakthroughs will only come through molecular cancer research on human tissue and this is only possible by close cooperation between clinicians and full-time research scientists. Our tumour bank and large clinical experience in the treatment of colorectal liver metastases provide an excellent opportunity to undertake this research. However, this requires funds to help establish this research scientist position. Any donation that you feel you could make would be helpful towards this purpose. Donations can be made directly to the Upper GI Surgical Unit by Tel: (02) 9438 2277.