[Mutation testing for non-small-cell lung cancer].

Background: Epidermal growth-factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKI) are a relatively new class of drugs for treatment of non-small-cell lung cancer. The national professional group for lung cancer, The Norwegian Lung Cancer Group, recommends that patients with non-small-cell lung cancer are tested for mutations in the EGFR gene. Here, we report the experience collected after the introduction of such testing in Norway in 2010.

Material And Method: Information on the number of patients tested, gender distribution, histopathological data and analysis results have been collected from the molecular-pathology laboratories at the university hospitals in Tromsø, Trondheim, Bergen and Oslo for the period from May 2010 to May 2011.

Results: During this period, altogether 1,058 patients with lung cancer were tested for mutations in the EGFR gene, equal to approximately half of all those who were diagnosed with non-small-cell lung cancer. A mutation was detected in 123 patients (11.6 per cent). There was a higher proportion of mutation-positive women than men (17.6 per cent, compared to 6.3 per cent, p < 0.001), and a lower proportion with squamous cell carcinoma than for other histopathological subtypes (3.0 per cent, compared to 12.9 per cent, p < 0.001). Of a total of 80 cytological tests, nine (11.3 per cent) were positive.

Interpretation: In light of the relatively high mutation frequency and a considerable number of positives in the group with squamous cell carcinoma, we recommend to continue the practice of mutation-testing all patients with non-small-cell lung cancer.