[Plasmablastic lymphoma presenting with plasmacytosis and polyclonal hypergammopathy].

A 72-year-old woman presented with generalized lymphadenopathies and plasmacytosis accompanied by polyclonal hypergammopathy. 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) showed FDG accumulation in the systemic lymph nodes, spleen, and multiple bones. Human immunodeficiency virus antibody was negative. Lymph node histologic findings showed a monotonous population of plasma cells with a starry-sky appearance. The cells were positive for CD19, λ, and Epstein-Barr virus-encoded RNA, and negative for CD20 and CD56. The MIB-1 index was 80%. A diagnosis of plasmablastic lymphoma with plasmacytosis and polyclonal hypergammopathy was made, and complete metabolic response was achieved after six cycles of dose-adjusted-EPOCH therapy (etoposide, prednisolone, vincristine, cyclophosphamide, and doxorubicin).

[Multiple myeloma with myelofibrosis at diagnosis and aggressive extramedullary relapse after autologous stem cell transplantation].

A 66-year-old man was diagnosed with symptomatic IgG-λ multiple myeloma based on the presence of anemia, thrombocytopenia, renal dysfunction, and a tumor on the right sixth rib. Bone marrow aspiration yielded a dry tap and biopsy revealed myelofibrosis grade 2. Partial response was achieved with Bd (bortezomib and dexamethasone) and VRd (bortezomib, lenalidomide, and dexamethasone). The patient received autologous stem cell transplantation, but the myeloma relapsed 3 months later, and liver tumors developed as well. DKd (daratumumab, carfilzomib, and dexamethasone) was administered, but the patient died due to disease progression. Autopsy revealed multiple extramedullary lesions in the liver, spleen, gallbladder, adrenal glands, kidneys, and multiple lymph nodes, as well as ascites.

Successful treatment with blinatumomab for acute lymphoblastic leukemia in an older adult patient complicated with hepatocarcinoma.

An 82-year-old man with Philadelphia chromosome-negative acute lymphoblastic leukemia (ALL) complicated by hepatocarcinoma was presented. Remission induction therapy of hyper-CVAD with half dose reduction achieved hematological complete remission (CR), but accompanied with elevated alanine aminotransferase and hyperbilirubinemia. The patient was thought intolerable for hyper-CVAD with half dose reduction due to liver toxicity, and treatment was switched to blinatumomab. Hematological CR was sustained after nine cycles of blinatumomab without exacerbation of liver dysfunction. After five courses of blinatumomab, hepatocarcinoma was treated successfully by trans-arterial chemoembolization. Two years after the diagnosis of ALL, the patient was alive in CR status of ALL.

Gilteritinib as Bridging and Posttransplant Maintenance for Relapsed Acute Myeloid Leukemia with FLT3-ITD Mutation Accompanied by Extramedullary Disease in Elderly.

A 69-year-old woman was diagnosed with acute myeloid leukemia (AML) with an FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) mutation. Complete remission (CR) was achieved after induction therapy, but AML resulted in a hematological relapse two months after the consolidation chemotherapy. Relapse was accompanied by multiple skin lesions that demonstrated leukemic cell infiltration as well as a drooping right eyelid with extroversion of the eye due to right oculomotor palsy. Gilteritinib was started as salvage therapy, and bone marrow blasts decreased to 0.8% after one month. Two months later, the eye symptoms improved, and the patient underwent cord blood transplantation (CBT). The skin lesions disappeared after the conditioning regimen, and the patient achieved CR status with complete donor chimerism at day 28. Gilteritinib was restarted as posttransplant maintenance therapy on day 53 of CBT. No adverse events other than mild hepatotoxicity were observed, and the patient was alive and in CR status, while continuing gilteritinib at one year and seven months after CBT. Bridging and posttransplant maintenance therapy with gilteritinib may be a promising therapeutic option for relapsed AML with the FLT3-ITD mutation in elderly patients.

[Busulfan/thiotepa followed by autologous peripheral blood stem cell transplantation for refractory diffuse large B-cell lymphoma accompanied by hypopyon].

A 54-year-old male patient, who presented with multiple lymphadenopathies, bilateral leg edema, and oscheohydrocele, was diagnosed with diffuse large B-cell lymphoma (DLBCL) stage IVB. His lymphadenopathies disappeared after six courses of R-CHOP therapy, which consist of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone); however, right hypopyon and partly remaining testicular soft tissue masses with fluorodeoxyglucose accumulation were observed. Lymphoma cell infiltration was observed in the aqueous humor of the right anterior chamber and testis, which indicates DLBCL progression. Hypopyon disappeared after the first course of intrathecal chemotherapy combined with R-HDMA therapy, which consists of rituximab and high-dose methotrexate/cytarabine, but recurred in the third course. The patient then underwent busulfan and thiotepa (BuTT) therapy followed by autologous peripheral blood stem cell transplantation (auto-PBSCT) after four courses of R-HDMA therapy. Hypopyon promptly disappeared after BuTT therapy and no hypopyon recurrence was observed 9 months after auto-PBSCT. Therefore, BuTT therapy is effective for hypopyon associated with refractory DLBCL.

Successful treatment with tirabrutinib for relapsed Bing-Neel syndrome following high-dose methotrexate and craniospinal irradiation.

A 63-year-old man was diagnosed with Waldenström's macroglobulinemia (WM). Six courses of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone) resulted in complete remission, but WM relapsed three years after R-CHOP. After six courses of BR (bendamustine, rituximab), the serum IgM level and CRP normalized. Four years after BR, the patient presented with muscle weakness, sensory disturbance, and myoclonus of lower limbs. T2-weighted magnetic resonance imaging (MRI) showed areas of signal hyperintensity with contrast enhancement in the right temporal and parietal lobes in brain parenchyma, medulla, bilateral basal ganglia, white matter of occipital lobe, and thoracic spinal cord at the Th2-11 levels. Open brain biopsy revealed diffuse proliferation of small lymphocytes and plasmacytoid lymphocytes on the brain surface and around cerebral blood vessels, resulting in a diagnosis of Bing-Neel syndrome (BNS). Two courses of R-MPV (rituximab, methotrexate, procarbazine, and vincristine) resulted in progressive disease, but the neurological symptoms and MRI findings improved following craniospinal irradiation of 30.6 Gy. Three years after craniospinal irradiation, T2-weighted MRI showed recurrence of BNS with progression of myoclonus of lower limbs and IgM elevation. Tirabrutinib was started for the second recurrence of WM and progression of BNS. Two months after the initiation of treatment with tirabrutinib, the myoclonus of lower limbs disappeared and the MRI findings showed improvement. Serum IgM levels decreased and no adverse events were observed. Tirabrutinib shows promise as a therapeutic option for relapsed BNS.

[Successful alectinib monotherapy for residual disease after brentuximab vedotin combined chemotherapy in ALK-positive anaplastic large cell lymphoma].

A 28-year-old male patient presented with multiple lymphadenopathies and extranodal masses. He was diagnosed with stage IVB ALK-positive anaplastic large cell lymphoma after the right axillary lymph node biopsy. A partial metabolic response with fluorodeoxyglucose accumulation was observed in the residual disease of the upper left hilar lymph node after eight courses of brentuximab vedotin, cyclophosphamide, adriamycin, and prednisolone. We started alectinib at 600 mg daily, which achieved a complete metabolic response (CMR) after three months. The CMR was maintained and alectinib was continuously administered without adverse events at the last follow up. Alectinib showed high efficacy and tolerability, though the optimal period and long-term adverse effects of administration remain unclear. Therefore, further studies are necessary.

Successful treatment with tirabrutinib for relapsed lymphoplasmacytic lymphoma complicated by Bing-Neel syndrome.

A 53-year-old woman was diagnosed with lymphoplasmacytic lymphoma (LPL)/Waldenström's macroglobulinemia (WM) in 2008. Six courses of R-COP (rituximab, cyclophosphamide, vincristine, and prednisolone) resulted in complete remission, but LPL/WM relapsed in 2015. After six courses of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone), the M-peak disappeared, but the patient presented with muscle weakness and sensory disturbance in the lower extremities. No lesions were apparent in the brain parenchyma, but T2-weighted magnetic resonance imaging (MRI) showed a signal-hyperintense area with contrast enhancement in the spinal cord at the C2-4 and Th2-3 levels, and cerebrospinal fluid (CSF) examination showed only a few mononuclear cells. In 2020, the patient started to require walking assistance, and MRI findings worsened. Neurologically, lower limb muscle strength was reduced (manual muscle test score 3), and sensations of touch and pain were about 30% of normal. Vibratory sensation was absent at the knees and medial malleoli, accompanied by dysuria due to neurogenic bladder. CSF cell count was 15/µl (all mononuclear cells). Bing-Neel syndrome (BNS) was diagnosed and tirabrutinib was started. Within 2 months of treatment, lower extremity muscle strength had normalized and MRI findings had improved. Tirabrutinib may offer a promising therapeutic option for BNS.

[Successful treatment of HHV8-negative effusion-based lymphoma with drainage of pleural effusion].

Two cases of human herpesvirus 8 (HHV8)-negative effusion-based lymphoma (EBL) involving unilateral pleural effusion that regressed only after drainage are reported. Cases 1 and 2 were 91- and 81-year-old men with right and left pleural effusion, respectively. No chemotherapy was administered to either patient because of their advanced age and the presence of cardiac comorbidities. They completely recovered after effusion drainage alone without relapse till the last observation. Thus, this study suggests that some patients with HHV8-negative EBL can be safely managed with effusion drainage alone.

[Intravenous immunoglobulin in combination with ibrutinib for the treatment of IgM-type M protein associated peripheral neuropathy complicated with chronic lymphocytic leukemia].

We report the case of a 79-year-old man with chronic lymphocytic leukemia (CLL) with IgM-kappa type monoclonal gammopathy according to immunophenotypes and a negative result for MYD88 L265P mutation of leukemic cells. Abnormal lymphocytes and IgM increased under observation, and he experienced paresthesia. The diagnosis of IgM-type M protein associated peripheral neuropathy was confirmed by nerve conduction test, and negativity of myelin-associated glycoprotein and glycolipid antibodies. He was placed on intravenous immunoglobulin (IVIg) in combination with ibrutinib. His symptoms dramatically subsided and did not recur. Treatment with IVIg and ibrutinib may be useful for the rare complication of peripheral neuropathy with CLL.