C4B and cancer: CH is associated with the normal process of aging in both healthy individuals and those with cancer.45, 46, 47 CHIP usually refers to mutations in driver genes.45, 46, 47 There is increasing evidence of CH mutations in genes usually mutated in solid tumors, including TP53, KRAS, GNAS, NRAS, and PIK3CA.45, 46, 47 CHIP variants in hematological malignancies are classified as mutations with a minimum VAF of 2%.45, 46, 47 However, in solid malignancies, VAFs of CH-related variants can be much lower (between 0.1% and 0.5%), and often overlap with the range of ctDNA-derived variants.45