Abstract
Urothelial bladder cancer (UBC) is a common malignancy with significant mortality worldwide. However, treatment options of UBC were mainly chemotherapy and immunotherapy since few targeted agents had shown efficacy in UBC. In recent studies, everolimus has showed antitumor activity in patients harboring aberrations in PI3K/Akt/mTOR pathway in multiple tumor types. Here we report a patient with metastatic UBC harboring a rare M1043I mutation of PIK3CA detected by DNA based next-generation sequencing. The patient received everolimus as first-line therapy after palliative transurethral resection. Within one months, the residual lymph node metastases achieved complete response and no more ostealgia was reported. To our knowledge, this is the first case reporting a significant benefit from everolimus in PIK3CA mutant UBC, suggesting the rare M1043I mutation variant may be a potential biomarker of sensitivity to everolimus. Further mechanism insights and clinical studies are needed to clarify the effectiveness of everolimus in patients with PIK3CA M1043I mutation.
Significant benefit of everolimus in a patient with urothelial bladder cancer harboring a rare M1043I mutation of PIK3CA