RESUMO
The background of this study is FGFR1 belongs to a family of four, high-affinity receptor tyrosine kinase and is a legitimate oncogene associated with uterine, cervical, prostate, bladder, colorectal and lung cancers. It is rarely concomitant in myeloid and lymphoid neoplasms but has an aggressive clinical course with a high mortality rate when present. Cytogenetic abnormalities involving the FGFR1 gene is most frequently observed in AML, MPN with eosinophilia, T-ALL and T-LBL with ZMYM2 gene being the most common fusion partner. Methods of this study was to authors report a series of 4 cases with FGFR1 rearrangements. Results is three patients presented as T-cell Lymphoblastic lymphoma (T-LBL) and one as mixed phenotype acute leukemia (MPAL). The T-LBL cases harboured the FGFR1/ ZMYM2 fusion and the MPAL case harbored the CNTRL/FGFR1 fusion as identified by conventional cytogenetics and confirmed by molecular studies. Conclusion is authors herewith describe the clinical, biochemical, molecular and cytogenetic features observed in these cases.