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BACKGROUND: Only a small proportion of patients with non-small cell lung cancer (NSCLC) attending radiotherapy centres were suitable for inclusion in a randomised trial which compared continuous hyperfractionated accelerated radiotherapy (CHART) with conventional radical radiotherapy. As this was thought to be partly due to delays in the referral of patients to clinical oncologists, a prospective study was performed to determine the interval between first report of symptoms and first radiotherapy treatment in patients with NSCLC. METHODS: The time course from first symptom to treatment was determined in all patients with NSCLC attending 10 cancer centres for radiotherapy to a primary tumour in a three month period. RESULTS: Only 5% of 484 patients were suitable for the trial of radical radiotherapy. The principal causes for exclusion were poor general condition (37%), too large a tumour (27%), and extrathoracic metastases (19%). The median time from first symptom to diagnosis was 13 weeks, from first symptom to first treatment 19 weeks, and from diagnosis to first treatment five weeks. In a quarter of the patients these intervals were greater than 25,33 weeks, and nine weeks, respectively. CONCLUSION: The reason for these long intervals needs investigation since earlier diagnosis and more immediate referral for consideration of treatment might increase the number of patients with NSCLC suitable for radical radiotherapy.

This study investigated whether impaired respiratory function affected the response to radiotherapy. A prospective study was performed in which lung function, arterial oxygen and haemoglobin concentration were examined, before treatment with radical radiotherapy, in 141 patients with advanced non-small cell lung cancer and head and neck cancer. The findings were considered to reflect the physiological conditions present at the time of radiotherapy and these were related to acute normal tissue reactions and tumour control. Although 53% of the patients showed some impairment of lung function and 47% demonstrated a haemoglobin oxygen saturation below the normal range, oxygen partial pressure was below expected levels in fewer patients (27%) and total arterial oxygen content was below normal in only 12% of patients. No correlation was found between the tests performed and the severity of acute morbidity or with local tumour control. In the patients with carcinoma of the bronchus, there was a trend for incomplete tumour control to be associated with a lower haemoglobin level, but this did not reach statistical significance. In patients selected for curative radiotherapy, lung function would not appear to be an important factor influencing the response of normal tissues or tumour to irradiation.

Non-small cell lung cancer remains the commonest cause of cancer death in men, and the second in women. Disease often presents late, with inoperable tumour in the chest and a high chance of occult distant metastases. Despite radical treatment with radiotherapy and chemotherapy, it is estimated that over 80% of patients die with disease in their chest (Cox 1991) As control of the primary tumour is a pre-requisite for long term survival, radiation oncologists have concentrated on novel fractionation schedules as a method of altering the biological effect of the irradiation given, attempting to improve local tumour control with reduced long term side-effects.

A century of the evolution of the fractionation of radiotherapy has brought clinical oncologists to the testing of protocols in randomized controlled clinical trials. The British Institute of Radiology's pioneering trials, together with more recent studies, are described and future developments suggested.

In a randomized controlled clinical trial of hyperbaric oxygen in the radiotherapy of carcinoma of the bladder a total of 241 cases were contributed by four radiotherapy centres in the United Kingdom. In this trial where in each centre identical radiotherapy was employed for both oxygen and air cases, no benefit was shown with the use of hyperbaric oxygen.

During recent years schemes of radiotherapy incorporating multiple treatments in one day have been introduced into the clinic. These can lead to a reduction in the overall duration of treatment (accelerated fractionation), an increase in the number of fractions in the same overall time (hyperfractionation), or a combination of both (Fowler, 1984). Two to five treatments have been given each day from Monday to Friday for 1, 2 or more weeks (Svoboda, 1978; Van der Schueren et al, 1985; Wang, 1985). It has usually been found necessary to reduce the individual dose increment from the conventional 1.8–2 Gy to between 1 Gy and 1.6 Gy but, even then, immediate reactions have prevented most workers from achieving a satisfactory total dose without interruption. Commonly, a split-course technique is employed with a rest period of 2–4 weeks to allow normal tissue reactions to settle before further radiotherapy is given. Retrospective comparisons in head and neck cancer have given improved results (Wang, 1985) but ra...