Colorectal cancer news

Positive developments in chemotherapy treatment

Cancer is one of the few areas of medicine where treatment is given intravenously rather than in a tablet or capsule form. However, in recent years, new ways of giving chemotherapy to patients have been developed.

Oral chemotherapy is one such example of a new way of providing treatment to patients, and is particularly attractive as it provides a more convenient method of receiving treatment. Currently there are over twenty oral chemotherapy treatments available. Although these may be as effective as intravenous treatments, intravenous chemotherapy is still widely used. There are various explanations for this, for example, oral chemotherapy is currently licensed for use in few types of cancer, and there is possibly is an assumption from both physicians and pharmaceutical companies that intravenous chemotherapy is more effective.

One area where oral chemotherapy is a suitable alternative is within breast and colorectal cancer. Traditionally, treatment is in the form of fluorouracil (5-FU) and is given intravenously. 5-FU cannot be given directly as a tablet or capsule because it is broken down by the gut, which means that it does not enter the bloodstream and causes too many side effects. Researchers therefore tried to find a way of delivering 5-FU to the tumour (cancer) without it being broken down by the gut. One such oral chemotherapy treatment, capecitabine, has been developed to deliver 5-FU directly to the cancer cells, where it is needed, and has been proven in trials to be just as if not more effective than intravenous 5-FU.

The future of oral chemotherapy is therefore positive. And, as some studies have shown, patients would prefer oral chemotherapy as long as it is effective as intravenous chemotherapy.

Doctors can sometimes find it difficult to decide on the most appropriate form of treatment for advanced colorectal cancer, especially when the available treatment options have not been compared directly. In these situations, they need to make the best indirect comparison possible. This is best done by evaluating whether a treatment is better than a type of bolus injection of fluorouracil (5-FU) called the Mayo Clinic regimen.

Better response rates were found in patients who were given capecitabine than with the Mayo Clinic regimen, whereas tegafur with uracil + leucovorin (LV) increased the risk of the disease progressing. Capecitabine also caused less diarrhoea, nausea, mouth sores and hair loss than the Mayo Clinic regimen. Patients who were given tegafur with uracil + LV also had fewer side effects than patients who were given ñ5-FU via the Mayo Clinic regimen.

Oral chemotherapy is more convenient for patients to take, but patients are not willing to sacrifice how effective their treatment is for convenience. Br J Cancer 2002;86:1670-1676.

ONeill VJ & Twelves CJ. Oral cancer treatment: developments in chemotherapy and beyond.Br J Cancer 2002; 87:933-937.

Comparing chemotherapy for colorectal cancer

Doctors can sometimes find it difficult to decide on the most appropriate form of treatment for advanced colorectal cancer, especially when the available treatment options have not been compared directly. In these situations, they need to make the best indirect comparison possible. This is best done by evaluating whether a treatment is better than a type of bolus injection of fluorouracil (5-FU) called the Mayo Clinic regimen.

Better response rates were found in patients who were given oral capecitabine than with the Mayo Clinic regimen, whereas oral tegafur with uracil + leucovorin (LV) increased the risk of the disease progressing. Capecitabine also caused less diarrhoea, nausea, mouth sores and hair loss than the Mayo Clinic regimen. Patients who were given tegafur with uracil + LV also had fewer side effects than patients who were given 5-FU via the Mayo Clinic regimen.

Oral chemotherapy is more convenient for patients to take, but patients are not willing to sacrifice how effective their treatment is for convenience.

Twelves CJ and Cassidy J. Which endpoints should we use in evaluating the use of novel fluoropyrimidine regimens in colorectal cancer. Br J Cancer 2002;86:1670-1676.

At risk individuals miss out on test for colon cancer

Patients at risk of developing hereditary nonpolyposis colorectal cancer (HNPCC) fear discrimination from health insurers and their own reaction to test results if they undergo testing for the disease. A team from the US National Cancer Institute in Bethesda, Maryland, USA investigated the attitudes of 165 adults from 15 families identified with HNPCC. Thirty-nine percent were worried that they themselves or a family member could lose health insurance if they were tested. Lack of awareness was also a problem, with over 60% of individuals saying they knew ìalmost nothing or relatively littleî about genetic testing for colon cancer.

Reuters Health, March 10, 2003

Western diet increases risk of colon cancer

A Western diet appears to increase the risk of colon cancer, while a prudent diet may reduce the risk. Research carried out at the Harvard School of Public Health in Boston, USA, found that women who ate a Western diet were 46% more likely to develop colon cancer than women who ate a prudent diet. A Western diet was defined as one containing high levels of red and processed meat, sweets, desserts, French fries and refined grains. A prudent diet was one containing a higher intake of fruits, vegetables, legumes, fish, poultry and whole grains.

Fung T, Hu FB, Fuchs C, et al. Major dietary patterns and the risk of colorectal cancer in women. Archives of Internal Medicine. 2003; 163:309-314.

Promising new drug for colorectal cancer

Patients with advanced colorectal cancer have shown promising responses to a drug that cuts off a tumourís blood supply when given with standard chemotherapy. The study, conducted at the UCLA Jonsson Cancer Center and published in January 2003, found that patients who were given the new drug Avastatin and chemotherapy did better than patients who received chemotherapy alone. Avastatin is a monoclonal antibody which targets a protein that promotes the growth of blood vessels. Tumours need their own supply of blood vessels to grow to a size of more than a few hundred cells. Results from another, larger trial are expected next year.

Better ways of treating colon cancer

Several new chemotherapeutic drugs, such as oxaliplatin and capecitabine, are now available for the treatment of colorectal cancer, with many more currently being tested in clinical trials. New types of therapy, such as vaccines, monoclonal antibodies, and drugs known as anti-angiogenics, which cut off the tumourís blood supply, are also being investigated.

Colon cancer awareness month

April 2003 is bowel cancer awareness month in the UK, where four people every hour are told they have bowel cancer. To raise awareness of the disease, charities, healthcare professionals, support groups and other organisations have come together to publicise the symptoms of bowel cancer. In the USA, President George W Bush declared March National Colorectal Cancer Awareness Month
http://www.bowelcancerforum.co.uk/html/month.html

New test for colon cancer

It may be possible to determine an individualís risk of developing colon cancer using a simple blood test. Researchers from Johns Hopkins University in Baltimore, USA say they have found a single genetic change that is much more common in people who have a family history of colon cancer, and is extremely common in people diagnosed with colon cancer. Further research is needed, but the researchers hope that the findings will lead to a simple screening test that will identify people with a genetic risk of developing the disease.

Reuters Health, 14 March 2003