How do you treat muscle-invasive and metastatic sarcomatoid bladder cancer?

This is a very challenging disease with poor prognosis and low response rate to therapy. If it's predominant or pure sarcomatoid, we are opening a neoadjuvant clinical trial with dose dense MVAC plus pembrolizumab before surgery. If there is no trial, I would do upfront radical cystectomy and PLND for localized disease. If it's metastatic disease, I would start with chemotherapy (dose dense MVAC or Gemzar/Cisplatin in fit patients for Urothelial mixed), or a sarcoma regimen for pure sarcomatoid.