LEUVEN UNIVERSITY in Belgium is the oldest university in the Low Countries. Erasmus was a student there. Five hundred years later, it is still flourishing. It educates half the practising doctors in Belgium, and is a leading medical and scientific centre. Last week it hosted a conference to discuss colorectal cancer and its treatments.

Until recently the results of treatment of colorectal cancer have hardly improved since the first part of the 20th century, when safe intra-abdominal surgery became established. When surgery alone is relied upon — and it is still the main treatment — the patient’s life is dependent on a good surgeon and early diagnosis. Better diagnosis with improved X-ray techniques and the development of colonoscopy, which allows for the examination of the whole bowel, as well as flexible sigmoidoscopy that allows the lower half of it to be viewed by the specialist, and samples taken for microscopic examination, have improved chances of survival. MRI and CT scanning have also been developed for examination of the bowel.

Improvements in treatment have not kept pace with those in diagnosis. If the diagnosis is made in the very earliest stage of the cancer, when the tumour hasn’t spread beyond the bowel wall, more than 90 per cent of patients will make a complete recovery after surgery.

If the cancer has breached the bowel wall, but there is no spread to the lymphatic glands, 80 per cent of patients will have no further trouble. If the cancer cells have invaded the nearby lymph nodes (glands), 60 per cent of patients will survive. If the cells have reached the more distant lymphatic glands, 30 per cent will have a good outlook. If the cancer has travelled to a more distant site, less than 5 per cent have an encouraging prognosis.

Short of improving early diagnosis, the clear need is for better treatments for those in whom early spread is evident. Improvement in chemotherapy would be the obvious answer.

Nearly 30 years ago fluorouracil given with folinic acid was introduced. This improved long-term survival, but not dramatically so. Within the past ten years three new chemotherapeutic drugs, oxaliplatin, irinotecan and capecitabine, have been introduced to combat this disease and have improved survival times. Last year at the American Society of Clinical Oncology’s annual international meeting in the US to discuss the treatment of cancer, the topic that filled the previously half-empty lecture halls was news of developments in chemotherapy for colorectal cancer.

Now it has been demonstrated that Avastin and Erbitux, two new drugs, can, when added separately to a different cocktail of chemotherapeutic agents, make an appreciable difference to survival time. Avastin (bevacizumab), is manufactured by Roche and Erbitux (cetuximab), by Merck.

It was Erbitux that was the subject of the meeting in Leuven, and Avastin that was presented later last week at a similar meeting in London. Both drugs work on a principle different from that achieved by the chemotherapeutic agents in the cocktail. Avastin and Erbitux interfere with angiogenesis, the formation of the new blood vessels that nourish the cancer and supply it with oxygen. Malignant tumours are highly vascular, as the cancers need a lavish blood supply to flourish. Inhibit the growth of the blood supply of a cancer and it is akin to both throttling and choking the tumour. These two anti-angiogenesis agents also block different epidermal growth factors that are essential for the development of the tumour’s blood vessels, the spread of the cancer tumour cells to new sites, as well as its growth in the original one.

Scientists have been working on ways of controlling angiogenesis for more than 30 years: these are the most encouraging results yet. Avastin and Erbitux don’t eradicate the disease, but when it is relatively advanced they have been shown to slow its progress and spread, and give the patient several more months of life.

Trial results of this sort are often the first indication that if a new drug had been used earlier in treatment it might have had an even more dramatic effect on a cancer that affects the 34,500 patients in the UK every year. Both drugs have also been tried in conjunction with chemotherapy to treat other cancers. Avastin is being studied in kidney, lung, pancreatic and advanced breast cancers; Erbitux has been given to patients with advanced cancer of the head and neck with apparently good results.

When Erasmus was at Leuven University his time was mainly occupied by religious and philosophical controversy. If his spirit was watching Professor Eric van Cutsem deliver his summary last week on the potential for good that antiangiogenesis drugs present he would have been impressed and surprised by the unanimous welcome that it received.

Colon Cancer Concern: 08708 506050; www.coloncancer.org.uk