A 22-year-old man sought medical advice for a swelling in the right side of the neck in December 2011. Histopathological examination of the lymph node biopsy initially suggested reactive lymphadenitis, on account of the only sparse presence of tumor cells. Bone marrow examination was performed in February 2012 revealed findings consistent with a diagnosis of T-cell lymphoblastic leukemia/lymphoma (T-LBL), and the patient was begun on remission induction therapy. The bone marrow showed an immature thymocytic pattern: cytoplasmic CD3+, surface CD3-, CD5+, CD4-, and CD8-. Re-assessment of the lymph node specimens revealed the same phenotype of the cells in the lymph node as that of the blasts in the bone marrow. In addition, a chromosomal aberration t(7;14)(p15;q32) was noted. The lymph node biopsy specimens were examined by paraffin-embedded tissue section-fluorescence in situ hybridization (PS-FISH), which revealed a fusion signal of T-cell receptor (TCR)γ gene (7p15) with T-cell leukemia/lymphoma 1A (TCL1A) gene (14q32.13). There have been at least 10 reported cases of T-LBL with t(7;14)(p15;q32), including the present case. However, this is the first reported case in which TCRγ-TCL1A translocation was confirmed by FISH.
Keywords: T lymphoblastic leukemia/lymphoma; TCL1A; TCR gamma; immature thymocytic pattern; t(7;14)(p15;q32).