PIK3CA and metastatic neoplasm: To assess viability of XPO1 as a therapeutic target in ER+ metastatic tumors, we utilized TCGA and METABRIC datasets and studied XPO1 mRNA expression with indicators of clinical outcome that help guide clinical decisions for management of metastatic ER+ tumors, e.g., PIK3CA, ESR1 and CCND1 expression.