Contribution of Next-generation Sequencing in a Case of Metastatic Breast Carcinoma with Pulmonary Lesions

Abstract

Next-Generation Sequencing (NGS) provide specific cancer-related gene-sequence information which can be helpful for diagnosis and clinical decision. Here we describe the case of a patient diagnosed with HER2 positive metastatic breast cancer and successive pulmonary lesions. Despite large immunohistochemical assays. It was not possible to distinguish on first thoracic specimen between primary lung adenocarcinoma and metastasis from breast carcinoma. NGS analysis on second thoracic sample detected somatic mutations in PiK3CA and TP53 genes. This mutation profile was identical to the previously resected adenocarcinoma. NGS contribute to diagnose metachronous primary lung carcinoma and to propose a thoracic treatment in addition to systemic management of metastatic breast carcinoma. Our case report emphasizes the usefulness of NGS to guide diagnosis and treatment in the objective of precision medicine.