Distribution of mutations among cHL histologic subtypes. (A) The heat map shows individual nonsynonymous somatic mutations detected in ctDNA of newly diagnosed cHL (n = 80) clustered according to the histological subtype. Each row represents a gene, and each column represents a primary tumor. The heat map was manually clustered to emphasize mutational co-occurrence. Mutations are color-coded in red. EBER status is shown above the heat map. The bar graph compares the prevalence of the most frequently mutated genes between nodular sclerosis (NSCHL) and all the other cHL subtypes (B), between nodular sclerosis (NSCHL) and mixed cellularity (MCCHL) cHL (C), and between EBER positive and negative cases (D).