EGFR amplification induces sensitivity to antiEGFR therapy in pancreatic acinar cell carcinoma

Abstract

Pancreatic acinar cell carcinoma (PACC) is a rare cancer. When the tumor is metastatic, few therapeutic options are available. Precision medicine using next-generation sequencing is defined by the administration of drugs based on the tumor genetic mutations. The usage of precision medicine for finding new therapeutic options for rare cancers is an emerging field. We have reported here the case of a patient bearing a multitreated metastatic PACC. This patient underwent somatic and constitutional exome analyses. The analyses revealed in the liver metastasis an amplification of the EGFR gene. Accordingly, the patient was treated with off-label usage of panitumumab. We observed rapid response with necrosis of the liver metastasis, while no efficacy was observed in the primary tumor. An exome analysis of the primary tumor revealed amplification of HER2 and MET with EGFR amplification. Such amplifications are known as a resistance mechanism to antiEGFR therapy. Our results suggest that exome analysis may be helpful to highlight targets in rare cancers, such as PACC. EGFR amplification in this pathology should be determined and could be used as a biomarker to propose antiEGFR therapy.

Keywords: Pancreatic cancer; Acinar cell carcinoma; Exome; Genetic mutations; Precision medicine

Core tip: The role of genetic profiling for therapy of rare cancer for precision medicine is currently under investigation. This case report reports, for the first time, that pancreatic acinar cell carcinoma could benefit from precision medicine and that EGFR gene amplification could be targetable by antiEGFR monoclonal antibody in this pathology.