Keeping Up With Testing Guidelines in Lung Cancer.

Abstract

The evaluation of lung carcinoma, especially lung adenocarcinoma, has undergone a radical change centered on molecular alterations that predict treatment response. Because these molecular alterations activate important oncogenic pathways, blockade provides a targeted approach to tumor therapy. As a result of this pairing of molecular event and therapy, tumors that harbor the alteration may be particularly responsive to a focused intervention, whereas those that do not are either less responsive or nonresponsive. Correct identification by this molecular classification approach is imperative, as ideal therapy is often dictated by this testing. For some alterations that are sufficiently common, a body of evidence has accrued to answer the question of why we test. For other alterations, this evidence has been harder to accrue for multifactorial reasons, for example, rarity of the alteration or more complex biology of response.In addition to the question of why we test, the how, what, and who/when are important considerations. Different testing platforms and methodologies have been evaluated and their performance parameters published. Biopsy and cytology samples are small and potentially exhausted, so the emerging use of blood samples is promising. And of course, of direct impact to the lung cancer patient are who should be tested and when in the course of their disease the testing should be performed.The “Updated Molecular Testing Guideline for the Selection of Lung Cancer Patients for Treatment With Targeted Tyrosine Kinase Inhibitors: Guideline From the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology”1 is a critical guideline to help answer these questions. However, inherent in the creation of such a guideline are gray areas that remain controversial, as well as new data accrual within what is a rapidly evolving field. This makes the document simultaneously an evidence-based set of recommendations and a dynamic glimpse of what its next iteration may contain. The commentaries that follow allow expert practitioners in the fields of thoracic pathology, oncology, and surgery to provide their insights into how these recommendations affect current and future practice, with the selected topics focused on areas of change and controversy.