Philadelphia chromosome-positive B-lymphoblastic lymphoma successfully treated with chemotherapy regimen containing imatinib: A rare case report and literature review.

Rationale B-lymphoblastic lymphoma (B-LBL) with BCR/ABL mutation (Ph+ B-LBL) is a rare type of cancer in both childhood and adults. Its clinical manifestations are similar to those of other types lymphoma. However, the targeted therapy can substantially improve the outcome of Ph+ B-LBL. Patient concerns A 19-year-old male with blood type O, Rh+ was admitted into our hospital on August 14, 2018, due to a recurrent fever and hypocytosis for 6 months. Diagnoses Routine blood exam showed pancytopenia. Bone marrow sample flow cytometry (FCM) exam showed abnormal cells were 2.27% of the nucleated cells, and was classified as the abnormal early B-lineage lymphoblastic cells. FISH testing showed the BCR/ABL positive cells were 13.6%. Karyotype analysis showed the 46, XY, t(9;22)(q34;q11). Molecular analysis of BCR/ABL mutation on ABL kinase showed that BCR/ABL T315I mutation. Patient was diagnosed with B-LBL with BCR/ABL mutation (Ph+ B-LBL). Interventions The patient was given chemotherapy with VDPI regimen (Vinorelbine, daunorubicin, prednisone, imatinib). Outcomes The patient achieved complete remission after 2 courses' treatment, followed by one course of clarithromycin regimen and another two courses of VDPI regimen. Patient remains in complete remission as of March 10, 2021. Lessons In B-LBL, a BCR/ABL mutation can happen in some of these patients. It is important to guide the pathologist to perform appropriate gene mutation detection, in addition to routine Immunohistochemistry test, to ensure an accurate diagnosis and use the targeted agent for treatment. According to the literature and our results, it seems that intensive chemotherapy plus TKI regimen is effective in inducing complete remission, and allo-SCT should be used as a long-term strategy.