Patient Selection for Radiotherapy

Many factors influence the selection of patients for high dose curative-intent radiotherapy. Performance status remains the most important of the patient factors. Patients with a low performance status have inferior survival and have the highest risk of toxicity. Patients with a bad performance status with important local symptoms, for example, pain, obstruction or superior venous cava syndrome, may still benefit from palliative radiotherapy. Significant co-morbidities such as COPD also influence overall survival, but are not consistently associated with inferior cause-specific survival or greater toxicity and are therefore not absolute contraindications to high-dose radiotherapy. Interstitial lung disease and autoimmune disorders such as systemic lupus erythematosus and scleroderma have been associated with enhanced intrinsic radiosensitivity of normal tissues and, therefore, a higher risk of serious toxicity resulting from radiotherapy. Tumor parameters such as local extent and nodal status remain powerful prognostic factors even in patients with comorbidities, as do biological characteristics of the tumor.