ERBB2 and carcinoma: Conversely, compared to HER2-positive carcinomas, HLBC-FPO score 2+ cases showed a very limited number of differentially mutated genes (2N = 0 and 2E = 1, Fisher’s exact test FDR adjustment), whereas HLBC-1 showed 4 differentially mutated genes (Fig. 4B–D, Additional file 6: Table S4).