The Efficacy of Neoadjuvant Atezolizumab Treatment in Patients With Advanced Urothelial Bladder Cancer According to the BASQ Classification

Recently, promising evidences that blocking PD-1 and PD-L1 is an efficacious way to treat advanced stage bladder cancer patients. Atezolimumab is the first PD-L1 inhibitor approved by US FDA for advanced UBC in June 2014. These novel agents will become the standard therapy for unhopeful UBC patients who fail to respond to cisplatin-based chemotherapy and finally, the first-line treatment would be changed from cisplatin-based chemotherapy to immune check point inhibitors for advanced UBC, particularly neoadjuvant setting.

Additionally, along with enormous analysis of genomic landscape of bladder cancer, a consensus was reached regarding the existence of a group of Basal-Squamous-like tumors - designated BASQ - characterized the high expression of KRT5/6 and KRT14 and low/undetectable expression of FOXA1 and GATA3. This novel molecular classification can improve the identification of optimal patient population for different treatment modalities. Specifically, luminal type and basal type may have different treatment response and prognosis after initial definitive treatment, such as neoadjuvant treatments.

However, there is no evidence for this topic, particularly the clinical efficacy of neoadjuvant PD-L1 inhibitors according to the BASQ classification in patients with advanced urothelial bladder cancer.