Lung cancer patients can now avoid painful biopsies by taking a simple blood test to help guide their treatment, a new study found.
The ‘liquid biopsy’ can be used to successfully identify complex DNA mutations in the cells of patients with advanced lung cancer.
The technique detects tiny pieces of tumour that are shed from cancer cells into the blood.
Study author Dr Shirish Gadgeel at University of Michigan, USA, said: “One of the biggest recent changes in the treatment of non-small cell lung cancer (NSCLC) has been our ability to identify targetable genetic mutations that drive the disease’s progression.
“But it is a major challenge to get a suitable tumour sample for analysis.
“We showed that liquid biopsy could be used to detect a complex type of driver mutation, called ALK, in patients with NSCLC.
“These then responded at least as well to targeted therapy as in previous studies using conventional biopsy techniques.”
Researchers studied more than 2,000 patients with untreated NSCLC taking part in the blood first assay screening trial (BFAST).
They all had blood tests to check for cancerous mutations using the state-of-the-art method.
The pioneering test successfully spotted that the notoriously hard-to-observe ALK gene had mutated in approximately five per cent of patients’ tumour DNA.
The tests then guided patients’ follow up treatment with alectinib – an oral cancer drug that targets the ALK gene mutation.
More than three quarters of the 87 patients treated did not show any signs of disease progressing in the following year.
Dr Gadgeel added: “Liquid biopsy identified a similar proportion of patients with ALK mutations to that typically seen with traditional biopsy and the results with alectinib compared well with those seen in a pivotal study of this treatment.”
Commenting on the study, Professor Alberto Bardelli, of Italy’s Turin University said: “Rearrangement in the ALK gene described in the study is typically difficult to detect.
“So it is an important advance to have shown that it can be detected in the blood and used to guide ALK inhibitor treatment which has then been demonstrated to be effective in patients with this mutation.”
He added: “It is encouraging to see that increasing numbers of patients with lung cancer can benefit from liquid biopsy to identify their disease mutation instead of tissue samples.
“At present the technology is quite expensive but as it becomes more widely used, the cost is likely to come down so that testing becomes more affordable and available in daily practice.”
The study’s findings will be presented at the ESMO (European Society for Medical Oncology) 2019 Congress running from September 27 to October 1 in Barcelona, Spain.
