MUC1 and renal pelvis/ureter urothelial carcinoma: Disrupting TRPV5 may lead to excessive calcium excretion that contributes to stone disease,20 and overexpression of MUC1 in UTUC has been linked to higher tumor grade and invasiveness.21,22 These observations point to a possible shared molecular network underpinning both stone formation and urothelial carcinogenesis.