Pericardial lesion analysis showed mutations in five genes: CD79A (R131fs*61), SETD2 (F1132fs*22), MLH1 (N168fs*4), MSH2 (F58Ilefs*27), TP53 (R175H), as well as a high tumour mutational burden and an intermediate microsatellite status. The gene discussed is MSH2; the disease is neoplasm.