Combining pre-operative chemotherapy and surgery increases the average chance of survival at five years by approximately 6% compared with surgery alone.
This conclusion was drawn by a team of Cochrane Researchers from the MRC Clinical Trials Unit in London after they identified 12 eligible randomised controlled trials. Data from seven of these trials were available from trial reports and were combined in a meta-analysis. The seven trials involved a total of 988 patients.
"This is currently the best estimate of the effectiveness of this therapy, but is based on a relatively small number of trials and patients," says lead researcher Sarah Burdett.
There was, however, insufficient data to break the patients down into sub-groups and see whether the effectiveness varies for different types of patients or stages of the disease.
This research is important because around the world more than a million new cases of lung cancer are diagnosed each year, around 80% of which are non-small cell lung cancer. In addition, many patients are only diagnosed after the disease has progressed, so survival rates across all stages of disease tend to be fairly low at around 14%, with only a quarter of patients being suitable for surgery.
The Cochrane Systematic Review found that using chemotherapy before surgery can reduce the size of tumours making the surgery simpler, and increasing the number of patients who may be candidates for surgery. The worry is, however, that having a course of chemotherapy delays the operation, and could therefore leave patients at risk of allowing the tumour to spread.
"The data suggest that the benefits of the chemotherapy outweigh the risks associated with the delay," says Burdett
A project to collect complete data on all patients included in all trials is ongoing and will be able to fully assess the value of this treatment.