Implementation of next generation sequencing into pediatric hematology-oncology practice: moving beyond actionable alterations
Hepatosplenic T-cell lymphoma is a rare, clinically aggressive lymphoma. Most cases represent a neoplasm of mature non-activated γδ T cells. Isochromosome 7q i(7)(q10) is thought to be the primary cytogenetic abnormality of this disease. In this paper, we describe a hepatosplenic γδ T-cell lymphoma case, with clonal ring chromosome 7 exemplifying an isochromosome 7q equivalent clonal aberration. A 62-year-old female patient presented with thrombocytopenia, isolated hepatosplenomegaly, and extremely high levels of LDH. Bone marrow work-up demonstrated a sinusoidal cytotoxic T-cell infiltrate with blastic features, while molecular studies verified monoclonal rearrangement for both TCR γ and TCR δ genes. Cytogenetics revealed clonal abnormalities including ring chromosome 7, trisomy 8, and der(19), while FISH analysis detected 7q amplification with partial deletion of 7p in ring chromosome 7. To the best of our knowledge, this is the first reported T-cell lymphoma case with ring chromosome 7.