Rearrangements involving KMT2A are common in de novo and therapy-related acute myeloid and lymphoblastic leukemias. There is a diverse recombinome associated with KMT2A involving at least 135 partner genes, with more being discovered due to advances in molecular genetic diagnostics. KMT2A-ARHGEF12 fusion has only rarely been reported, in five cases of acute leukemia and a single case of high-grade B-cell lymphoma. We present a 12-year-old boy with high-grade B-cell lymphoma and KMT2A-ARHGEF12 fusion, whose clinical, morphologic, phenotypic and genotypic profile is strikingly similar to the other case of high grade B cell lymphoma, both otherwise perfectly mimicking Burkitt lymphoma.

涉及重排KMT2A是常用从头和治疗相关的急性髓细胞和淋巴细胞白血病。有一个与KMT2A相关的多样化重组体，涉及至少 135 个伙伴基因，由于分子遗传诊断学的进步，更多的基因被发现。KMT2A-ARHGEF12融合很少被报道，在 5 例急性白血病和 1 例高级别 B 细胞淋巴瘤中。我们介绍了一名患有高级别 B 细胞淋巴瘤和KMT2A-ARHGEF12融合的 12 岁男孩，其临床、形态学、表型和基因型特征与另一例高级别 B 细胞淋巴瘤极为相似，否则两者都非常相似伯基特淋巴瘤。