BRAF and isolated hemihyperplasia: Mody et al. studied ctDNA in 124 patients with advanced BTC (70% with IH-CCA) and found treatable alterations in 21% of patients (BRAF [2%]; aERBB2 [5%]; fFGFR2 [2%]; mFGFR2 [2%]; and mIDH1 [10%]) [50].