Protective radiotherapy to prevent the spread of lung cancer to the brain may be the most effective treatment to extend patient survival, the Clinical Oncological Society of Australia’s annual scientific meeting in Brisbane will hear today.
Associate Professor David Ball, of the Peter MacCallum Cancer Centre in Melbourne, will present the results of a study that showed moderate dose irradiation reduced metastasis from 50 per cent to less than 10 per cent in small cell lung cancer patients who had achieved remission. Of the 90 patients involved in the study, 30 per cent of those who had undergone preventive irradiation treatment applied to their brains were alive after five years, compared with around 5 per cent of those who had not had the treatment. “Cerebral metastasis – the spread of cancer cells to the brain – is one of the major causes of early lung cancer death and fatal relapse in patients who had achieved remission,” A/Professor Ball said. “This is largely because the brain is a sanctuary for cancer cells, often offering them a defence from the therapeutic effects of chemotherapy and surgery.” “Radiotherapy has been shown to be the most effective treatment modality for controlling or eliminating cancer cells in the brain.” While small cell lung cancer accounts for only 15 per cent of cases, A/Professor Ball said the treatment, known as prophylactic cranial irradiation (PCI), could potentially provide benefit to patients with the more prevalent non-small cell lung cancer. He said more study was required, but the existing evidence was encouraging. A large-scale clinical trial to measure the potential benefit of PCI in non-small cell lung cancer was underway in the US. “If we can prevent lung cancer spreading to the brain, or eliminate the sanctuary effect that causes cells in the brain to trigger relapse, we hope to extend the survival of a large proportion of lung cancer patients.”(Source: The Cancer Council: November 2005.)