Table 11. Studies reporting outcomes with neoadjuvant immunotherapy (Pembrolizumab).

Author (year)	Pathologic complete response	Pathologic downstaging	Median follow up after cystectomy	Survival outcomes after cystectomy	Major independent factor(s) other than histologic phenotype affecting response/outcomes analyzed	Comments
Neechi (4) (2020), n=114 (VH n=34) VH patients were stratified into two groups	pCR to neoadjuvant pembrolizumab compared between predominant VH, non-predominant VH and conventional UC was 16%, 53% and 39% respectively	Pathologic downstaging to pT ≤ 1N0 was 42%, 67% and 56% in predominant VH, non-predominant VH and conventional UC patients respectively	–	–	A high tumor mutational burden and combined positive score for PD-L1 expression was found to correlate with response to therapy	The efficacy of neoadjuvant pembrolizumab was significantly lower in patients with predominant VH. However, a subgroup analysis showed the response to be greatest among patients with the squamous differentiation and lymphoepithelioma-like VH
					FGFR3 mutations had no correlation with response

VH, variant histology; pCR, pathologic complete response; UC, urothelial carcinoma; PD-L1, programmed death ligand 1; FGFR3, fibroblast growth factor receptor 3.