PIK3CA and neoplasm: The patient was initially treated with radiation followed by chemotherapy (Fig 1) and at this time her tumor was screened for oncogenic mutations using a multiplexed mass spectroscopy-based assay that revealed the presence of PIK3CA R88Q and Q546R in the primary tumor.[29] As a result, she entered a phase I clinical trial of a PI3 kinase inhibitor and had a partial response that lasted 12 months.