Identification of actionable mutations in malignant pleural mesothelioma.

BACKGROUND

Genetic alterations in malignant pleural mesothelioma (MPM) patients are not well-understood.

PATIENTS AND

METHODS

Surgical specimens and tumor biopsies from 42 patients with MPM were collected from 2003 to 2012. The samples were analyzed for mutations in EGFR, KRAS, BRAF, PIK3CA, NRAS, MEK1, AKT1, PTEN, and HER2 and amplifications in EGFR, MET, PIK3CA, FGFR1, and FGFR2. In addition, 21 patients' samples were analyzed using amplicon-based massively parallel sequencing for actionable mutations in 48 cancer-related genes.

RESULTS

Genetic alterations were detected in 4 patients (one KRAS mutation and 3 PIK3CA amplifications). Patients harboring genetic alterations showed significantly poorer survival than patients with no genetic alterations. Moreover, significance was maintained if the patients only harbored PIK3CA amplification. A total 16 genetic mutations were identified in the 9 patients' samples (4 TP53 mutations, 3 APC mutations, 3 PIK3CA mutations, and 2 VHL mutations, etc.) by deep sequencing.

CONCLUSIONS

Genetic alterations that are potential targets for molecular targeted therapy were detected in MPM. Amplicon-based massively parallel sequencing was shown to have the advantage of more comprehensive genetic analysis. Further investigation in a larger cohort is necessary to uncover more targetable genetic alterations in MPM and to validate their clinical significance.