A 46-year-old woman was diagnosed with acute promyelocytic leukemia (APL). The patient was given remission induction therapy with all-trans retinoic acid, and complete remission was achieved. Despite consolidation therapies with arsenic trioxide, daunorubicin and cytosine arabinoside (AraC), and gemtuzumab ozogamicin as well as maintenance therapy with tamibarotene, the patient experienced a relapse 6 months after the start of maintenance therapy. She was then given re-induction therapy with idarubicin+AraC and high-dose AraC, but remission was not achieved. Since the coordination of the unrelated donor had been completed at this time, she then underwent bone marrow transplantation with pre-conditioning of 4 Gy total body irradiation, fludarabine, and busulfan. However, on the 12th day after the transplantation, APL cells appeared in the peripheral blood and the disease progressed rapidly leading to the patient’s death on the 15th day after the transplantation. APL usually has a good prognosis, and relapsed cases are often cured by autologous stem cell transplantation. However, this case was highly refractory to treatment and the patient deteriorated rapidly after the transplantation, suggesting a different pathogenesis from the usual from of APL.

In this study, we report a rare case of immune thrombocytopenic purpura (ITP) associated with the worsening of Kimura’s disease. A 47-year-old Japanese man with a pruritic rash and swollen inguinal lymph nodes was diagnosed with Kimura’s disease on performing a right inguinal lymph node biopsy. Thrombocytopenia ensued after the diagnosis of Kimura’s disease, and fluctuations in the platelet count were observed along with the pathology of Kimura’s disease. The platelet count fluctuated repeatedly with the relapse of Kimura’s disease and a diagnosis of a combination of Kimura’s disease and ITP was made through lymph node regeneration and bone marrow examination. Treatment with prednisolone (1 mg/kg/day) was initiated for Kimura’s disease and ITP, and lymphadenopathy and platelet count improved promptly. Since then, the dose of prednisolone has been gradually reduced, and the disease status of both Kimura’s disease and ITP has been controlled.

An 83-year-old man was diagnosed with hairy cell leukemia (HCL). He was treated with cladribine and achieved partial remission. However, pancytopenia due to HCL bone marrow involvement progressed slowly. Nine years later, he developed rectal cancer. Prior to the surgery, endoscopy-assisted submucosal ink injection was performed to identify the area of lower intestinal lesions. The following day, he developed septic peritonitis with shock status, perhaps due to his neutropenia and ink injection procedures. Surgical resection of the cancer was presumed unfeasible; therefore, radiation was performed. Several months later, bone marrow examination revealed HCL infiltration with reticulin fibrosis. Chemotherapy regimens with purine nucleoside analogs, which are the standard treatments for HCL, might accentuate the progression of his rectal cancer and enhance the development of severe infections. Therefore, interferon (IFN) -α was administered as an alternative therapy. Three months later, pancytopenia resolved, and bone marrow examination revealed a remarkable improvement in HCL infiltration and marrow fibrosis. With IFN-α therapy, the patient successfully underwent surgical resection of the rectal cancer. Using INF-α, a prompt recovery from pancytopenia might be expected even in a patient with advanced HCL, who requires surgical treatment for a concomitant cancer.

In this study, we report a case of a 77-year-old woman who was presented with anemia in the winter of 2002. She was diagnosed with cold agglutinin disease (CAD) and treated with corticosteroids. Further, her hemoglobin levels were maintained between 7.0 g/dl and 8.0 g/dl. In May 2019, mature peripheral blood lymphocytes increased with exacerbation of hemolytic anemia. The lymphocytes were positive for CD19 and CD20, but negative for CD5, CD10, and CD23. Additionally, they were positive for cell surface IgM-κ. The B-cell neoplasm could not be further subclassified due to the lack of BCL2-IgH and BCL1-IgH rearrangement and morphology. The IgM-κ-type M-protein was found in serum, and the direct Coombs test was negative for IgG but positive for C3b/C3d. These findings suggested that small B-cell neoplasm-associated M-protein was involved in the development of CAD through complement activation. Based on the presence of TP53 deletion, the patient was treated with ibrutinib monotherapy. Although hemolysis rapidly improved with a dramatic decrease in lymphocytes, she died from a cerebral hemorrhage. It is assumed that ibrutinib improved CAD through suppression of small B-cell neoplasm-related M-protein. CAD can precede lymphoproliferative disorders; however, the risk of ibrutinib-associated hemorrhage should be noted.

The Japanese Society of Hematology recently published on acute exacerbation of immune-mediated thrombocytopenia (ITP) after mRNA-based severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. In addition, there is a growing concern for the development of the newly diagnosed ITP after SARS-CoV-2 vaccination. Herein, we report two cases of severe thrombocytopenia associated with bleeding tendencies at 4 and 14 days after BNT162b2 mRNA vaccination. Platelet counts returned to normal following platelet transfusion or treatment with intravenous immunoglobulin and dexamethasone. To our knowledge at the time of the draft of this manuscript, nine cases of SARS-CoV-2 vaccine-induced ITP have been reported. Although most patients showed favorable clinical courses similar to that of our cases, critical thrombocytopenia can lead to unfavorable outcomes. A national survey may be required to examine the causal relationship between SARS-CoV-2 vaccination and the emergence of the newly diagnosed ITP and clinical outcomes of vaccine-induced thrombocytopenia.

A 95-year-old male developed general subcutaneous petechiae, tongue hematoma, and melena two days after receiving the second BNT162b2 mRNA COVID-19 vaccine. Two days later, his platelet count decreased to below 1,000/µl. Laboratory testing was positive for a slight increase in D-dimer, Helicobacter pylori (H. pylori) immunoglobulin G (IgG) antibody, lupus anticoagulant, and anticardiolipin IgG antibody levels. There were no severe infections or symptomatic thrombosis. Platelet transfusions were transiently effective. He was diagnosed with newly developed immune thrombocytopenia (ITP). We administered prednisolone (PSL) at 0.5 mg/kg/day and intravenous immunoglobulin (IVIG) at 0.4 g/kg/day. From the following day, his platelet count rapidly increased, with an improvement in bleeding tendency. H. pylori was eradicated after platelet count recovery. Thrombocytopenia did not relapse although PSL was tapered three months later. Causes of thrombocytopenia after SARS-CoV-2 vaccination include ITP, vaccine-induced immune thrombotic thrombocytopenia, and thrombotic thrombocytopenic purpura. Differential diagnosis is important to determine the proper therapy. Case reports of newly diagnosed ITP after SARS-CoV-2 vaccination have been increasing recently. In these cases, including ours, the responses to steroids and IVIG were good. Further follow-up studies are needed to manage thrombocytopenia following SARS-CoV-2 vaccination.