A real-world study has suggested diagnostic testing for targeted therapy of lung cancer patients is not being delivered effectively, which could impact their survival.
Data reveal that around a quarter of advanced lung cancer patients in Europe, the US and Asia are not receiving epidermal growth factor receptor (EGFR) mutation testing prior to starting treatment, in contravention of clinical guidelines.
Moreover, more than half of the 562 oncologists surveyed said their treatment selection was not guided by a patient’s EGFR mutation status, once again against current clinical advice that indicates that this should be taken into consideration before starting therapy.
Testing rates for EGFR status also varied between regions, with 92% of newly diagnosed patients in Asia being tested compared to 77% in Europe and 76% in North America.
There were also regional differences in when patients started therapy, with 12% of patients in Asia beginning treatment before EGFR results were in, compared to 30% of European patients.
Among the principle reasons for not testing patients, oncologists cited tumour histology, inadequate tissue samples, poor patient fitness and test results taking too long to come back from the lab.
The study was sponsored by Boehringer Ingelheim, which makes EGFR inhibitor Giotrif (afatanib) that was approved for non-small cell lung cancer (NSCLC) in 2013. Other drugs in the class approved to treat lung cancer include Iressa (gefitinib) from AstraZeneca (AZ) and Roche/OSI’s Tarceva (erlotinib), with several more coming through the pipeline.
“The arrival of a new group of targeted EGFR inhibitors for the treatment of lung cancer driven by mutations in the EGFR gene has brought with it a new requirement for diagnostic laboratories to implement genetic testing,” said lead investigator James Spicer from King’s College London at Guy’s Hospital, London, UK.
“For many institutions this has represented a significant departure from traditional pathology, which had previously focused only on microscopic examinations of tumour tissue,” he added.
While the implications of the incomplete testing and start of therapy without reference to EGFR status were not monitored in the trial, it is reasonable to assume that the findings “may impact treatment effectiveness and survival,” according to the researchers.
Commenting on the study, Professor Silvia Novello from the Department of Oncology at the University of Turin, Italy, said that while interpretation of the findings is limited by the fact that it is a survey rather than an observational trial, it helps to highlight the causes of the problem.
The results suggest “incomplete integration of multidisciplinary oncology teams” and “an imperfect knowledge of data regarding the use of EGFR inhibitors” are causal factors, she said.