A new regime of radiotherapy designed to benefit lung cancer patients has been developed by Cancer Research UK scientists.
Treating patients with a higher dose of radiotherapy, but giving them weekends off to recover during an 18 day intensive course of treatment, can improve tumour control and increase survival rates says a report1 published today.
The study, led by Professor Michele Saunders, has used computer models to predict that the new regime could improve tumour control from 19 per cent under the current gold standard system to 33 per cent.
The study used mathematical calculations based on knowledge of tumours and normal tissues to see what would happen when the new system was implemented. The results of the calculations were then compared with the results of the new treatment when it was given to patients and found to be the same.
The new system was no more toxic, there was no increase in tissue damage and side effects increased only very slightly by between two and four per cent. In fact by giving patients weekends off it allowed a greater repair time for some tissue.
Earlier studies showed that the gold standard treatment known as CHART, an intensive scheme which gives patients three doses of radiation a day for 12 consecutive days, was more effective than conventional radiotherapy which is a daily dose five days a week spread over five to six weeks.
Prof Saunders explained that the aim was to build on CHART by giving a higher dose of radiation but one which was still tolerable to the patient and gave them a break at weekends. This would be known as CHARTWEL (CHART WEEK-END-LESS).
She also explained that CHARTWEL was more pragmatic for the health service since radiographers are only allowed to work around 36 hours a week and there is a shortage of staff especially at weekends.
“Although CHART has been shown to be more effective than conventional radiotherapy it is used in fewer than 10 hospitals in the country because we don’t have radiographers to staff the machines at weekends,” says Prof Saunders.
A companion study published in the same journal, and also led by Prof Saunders, shows how a combination of CHARTWEL and chemotherapy can greatly improve tumour control in non small cell lung cancer patients.
When patients had a combination of treatments, tumour remission increased from 55 per cent in those who had CHARTWEL alone to 72 per cent who received both CHARTWEL and chemotherapy.
“Our studies were small but the results indicate that while the CHARTWEL radiotherapy and chemotherapy combination may not lead to dramatic improvement in survival rates for patients with non small cell lung cancer, the small improvements it does show could translate into substantial gain with thousands of patients surviving five years or more per year in Europe,” says Prof Saunders.
“It is clear that there is now a need for randomised clinical trials to take the work forward and, if successful, make the treatment available throughout the country.”
Sir Paul Nurse, Chief Executive of Cancer Research UK, says: “One of our priorities at Cancer Research UK is to find ways of benefiting patients who suffer from cancer by improving treatments and highlighting ways in which it is possible to help prevent the disease. The proven effectiveness of CHART and the prospective success of CHARTWEL shows we are on the right track when looking at improved ways of treating lung cancer patients. If we are able to introduce treatment regimes which have a secondary benefit to our already overstretched health service then that is a welcome bonus.”
- Clinical Oncology: 14 (5) pp.353-360; 372-381
Non small cell lung cancer is the commonest form of lung cancer.
CHART is Continuous Hyperfractionated Accelerated Radiotherapy