This collaborative study with Foundation Medicine (Cambridge, Massachusetts), using very sensitive deep sequencing, partially mitigates some of the anxiety generated by the identification of tumor heterogeneity. While our data in lung cancer confirm that such heterogeneity exists, they also indicate that there is a high level of concordance in recurrent driver mutations between primary tumors and their metastases. This is reassuring for clinicians when they make a therapeutic decision on the basis of a molecular portrait.

With regard to our future studies in this area, the matched primary tumors and metastases analyzed in the study were surgical samples. Therefore, there is a need to reproduce such a study in metastatic patients who present with multiple metastatic sites. To this end, multiple computed tomography–guided organ biopsies of the metastasis are necessary to harvest the relevant biologic material on which next-generation sequencing analysis can be performed.

The acquisition of such material is ongoing at Institut Gustave Roussy under the umbrella of a prospective trial called MOSCATO (Molecular Screening for Cancer Treatment Optimization). Preliminary results of the trial were presented at the 2013 ASCO Annual Meeting by Dr. Antoine Hollebecque.¹ ■

Disclosure: Dr. Soria reported no potential conflicts of interest.

Reference

1. Hollebecque A, Massard C, De Baere T, et al: Molecular screening for cancer treatment optimization (MOSCATO 01): A prospective molecular triage trial—interim results. 2013 ASCO Annual Meeting. Abstract 2512. Presented June 1, 2013.