Postoperative radiotherapy for non‐small cell lung cancer
Abstract
Background
The role of postoperative radiotherapy (PORT) in the treatment of patients with completely resected non‐small cell lung cancer was not clear. A systematic review and quantitative meta‐analysis were therefore undertaken to evaluate the available evidence from randomised trials.
Objectives
To evaluate the effect of postoperative radiotherapy on survival and recurrence in patients with completely resected non‐small cell lung cancer. To investigate whether or not pre‐defined patient subgroups benefit more or less from PORT.
Search methods
We supplemented MEDLINE and CANCERLIT searches with information from trial registers, by handsearching relevant meeting proceedings and by discussion with relevant trialists and organisations.
Selection criteria
Both published and unpublished trials were eligible for inclusion provided the patients had undergone a complete resection; had been randomised between radiotherapy and no immediate further treatment; that the method of randomisation precluded prior knowledge of the treatment to be assigned; and that recruitment was after 1965.
Data collection and analysis
We carried out a quantitative meta‐analysis using updated information from individual patients from all available randomised trials. We sought data from all patients randomised in all eligible trials directly from those responsible. We obtained updated information on survival, recurrence and date of last follow up. To avoid potential bias, we requested information for all randomised patients including those who had been excluded from the investigators' original analyses.
Main results
We included 2343 patients from 11 trials (median follow up of 4.4 years). The results showed a significant adverse effect of PORT on survival with a hazard ratio of 1.18 or an 18% relative increase in the risk of death. This is equivalent to an absolute detriment of 5% at two years (95% CI 2% to 9%), reducing overall survival from 58% to 53%. Exploratory subgroup analyses suggested that this detrimental effect was most pronounced for patients with stage I/II, N0‐N1 disease, whereas for stage III, N2 patients there was no clear evidence of an adverse effect.
Authors' conclusions
PORT is detrimental to patients with early stage completely resected non‐small cell lung cancer and should not be used in the routine treatment of such patients. The role of PORT in the treatment of N2 tumours is not clear and may justify further research.
PICOs
Plain language summary
Postoperative radiotherapy for non‐small cell lung cancer
Non‐small cell lung cancer is the most common type of lung cancer. If this type of lung cancer has not spread, standard treatment is an operation to remove the tumour. Trials of a treatment called Post‐Operative Radiotherapy Treatment (PORT), which involves giving x‐ray treatment after the operation, have been carried out. These trials have been combined in this review, which found that giving PORT did not help people live longer. Fewer people given PORT treatment lived for two years after the operation (53%) than those who were not given PORT (58%). The treatment seemed to be harmful to patients in the early stages of the disease whose cancer had not spread. For those with more advanced disease, the evidence is less clear. However, even for these patients there is no indication that PORT is beneficial. Radiotherapy given after successful removal of tumour at operation is not beneficial for patients with non‐small cell lung cancer and should not be used as routine treatment. Further research with new types of radiotherapy may be justified.
