Adult T-cell leukemia-lymphoma (ATL) is one of the most intractable peripheral T-cell neoplasms caused by human T-cell leukemia virus type I (HTLV-1) infection. Recently, the incidence of HTLV-1 infection and ATL has increased in non-endemic metropolitan areas in Japan. This retrospective study evaluated the clinical features and outcomes of patients with aggressive ATL aged 70 years or younger treated at a core hospital in Tokyo between 2004 and 2016. The median follow-up was 124.4 months for survivors. Among the 71 patients, 46 (64.8%) underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT). The 3 year overall survival rate was 45.7% in allo-HSCT group versus 0% in non-allo-HSCT group. Patients who achieved complete/partial remission before allo-HSCT had a significantly better survival rate than those with stable/progressive disease (51.4% vs 27.3%). The 2 year cumulative incidence of relapse/progression and non-relapse mortality after allo-HSCT was 41.3% and 21.7%, respectively. In this study, a large percentage of patients underwent allo-HSCT and achieved favorable outcomes. As cases continue to rise in metropolitan areas, core hospitals will play a critical role in ATL treatment.

Despite the emergence of monoclonal antibodies, the prognosis of patients with multiple myeloma (MM) with extramedullary disease remains poor. The present report describes a rare case of daratumumab-refractory MM that was successfully treated with elotuzumab, pomalidomide and dexamethasone. A 66-year-old male patient diagnosed with MM was treated with bortezomib, lenalidomide and dexamethasone, followed by high-dose chemotherapy and autologous stem cell transplantation. Thereafter, the patient was treated with lenalidomide and dexamethasone as maintenance therapy. This was changed to daratumumab, bortezomib and dexamethasone when new paraskeletal lesions were identified, resulting in marked tumor shrinkage. After 15 months, an increase in serum monoclonal protein levels, development of a skeletal lesion in the right second rib and extramedullary disease of the right thoracic mediastinal lymph nodes were noted. Treatment with elotuzumab, pomalidomide and dexamethasone (EPd) resulted in expeditious symptomatic improvement and regression of the lesions. Notably, during daratumumab, bortezomib and dexamethasone treatment, lymphocyte counts gradually increased to a level at which elotuzumab was sufficiently effective. EPd might be a promising strategy for the treatment of patients with relapsed extramedullary MM while on daratumumab treatment.

Since the field of drug discovery has seen a rise in the use of primary tumor specimens (PTS) derived from patients with hematological malignancies as live materials in ex vivo drug treatments in late 2010s, they have discovered many intriguing phenotypes of AML cells that can lead to therapeutic insights of this disease category. However, when we consider the fact that current methods in ex vivo drug screenings are not using the most updated culture and cell processing methodology, it is highly expected that modernization of cell processing and analyzing procedures will enable us to detect phenotypes of PTS at a higher resolution. Herein, we have installed our own updated methods in multimodal categories. Even though the number of primary tumor specimens in the screening cohort is not comparable to the ones in other studies using AML PTS, (24 cases of AML, 3 cases of CML, and 1 case of MPN, while we ongoingly recruit more cells), our approach is characterized by its full-automation both in cell processing and data acquisitions using multicolor flow cytometry, as well as updated ex vivo culture methods after optimization using different culture media. We harvested cells for flow cytometry as of day 0, 3, and 6. In a monotherapy section, 24 compounds (6 conventional chemotherapy drugs, 10 epigenetic inhibitors, 4 kinase inhibitors including a FLT3 inhibitor, 3 signal transduction inhibitors, and Venetoclax) were included, while 3 different combination therapies (IDR+ AraC, Ven + 5-Aza, and Ven + AraC) were performed using 6x6 matrix layouts. Drugs were prepared in 384-well plates using a computationally controlled drug dispenser. Using those updated systems, we could discover; 1) Those fully-automated high-throughput platform needs their own optimizations regarding seeding numbers, liquid handling methods, and optimal plastic vessels with low inherent variations of results. 2) PTS are well tolerable to up to 6 days of ex vivo culture 3) Choosing optimal time points for each of the drugs ensures more accurate representation of their drug activities. For example, epigenetic inhibitors have tendency to show better results on day 6 rather than day 3. 4) Multicolor flow cytometry provides previously unseen differences in drug activity profiles upon different clusters, which had not been visible from bulk-grade sensitivity profiling, such as colorimetric viability assay. Those specimens were genetically profiled by whole genome/ exome sequencing, as well as other multi-omics analyses (Bulk RNA seq, methylome analysis, and scRNA seq). 5) Optimizations of ex vivo culture methods not only ensure our better quality of these 6-day drug effects, but also extend the possibility of PTS for further applications by allowing leukemia stem cell fractions to be maintained in vitro for longer periods of time. They include long-term culture and ex vivo expansion of leukemic stem cells using the most updated serum-free liquid culture, and further gene modifications using various vectors. Collectively, our platform for DSS confers next-generation use of primary patient-derived biomaterials so that even a small- to middle-sized group can conduct these complexed assays to test their hypotheses based on primary specimens, which had been possible only in high-volume multi-institutional alliances.

PDF file - 67KB, FISH analysis of HTLV-1-infected cells.

PDF file - 51KB, Representative flow cytometric analysis of a patient with smoldering-type ATL (patient no. 12).

PDF file - 64KB, Summary of this study.

PDF file - 41KB, Temporal changes in the data of a chronic-type ATL patient.

XLSX file - 47KB, Clinical profile and flow cytometry data of patients with HTLV-1 infection and normal controls.

PDF file - 29KB, Proportion of each subpopulation in the CADM1 vs. CD7 plot in normal controls.

A 72-year-old woman was diagnosed with extranodal NK/T cell lymphoma of the right nasal cavity and received sequential radiochemotherapy comprising focal radiotherapy and THP-COP chemotherapy. Showed a complete tumor response to the treatment; however, the tumor recurred in the contralateral right nasal cavity 15 years after the initial treatment. This was judged to be a marginal recurrence in the radiation field. After four cycles of dexamethasone, methotrexate, ifosfamide, L-asparaginase, and etoposide (SMILE) chemotherapy, a second complete response was achieved. It is possible that another recurrence occurs in the future, and if the lesion is localized at the time of recurrence, it may be possible to control the disease again. Careful follow-up is considered necessary.

Lineage switches in acute leukemia occur rarely, and the underlying mechanisms are poorly understood. Herein, we report the case of an elderly patient with leukemia in which the leukemia started as B-cell acute lymphoblastic leukemia (B-ALL) and later changed to B- and T-cell mixed phenotype acute leukemia (MPAL) and acute myeloid leukemia (AML) during consecutive induction chemotherapy treatments. A 65-year-old woman was initially diagnosed with Philadelphia chromosome-negative B-ALL primarily expressing TdT/CD34/HLA-DR; more than 20% of the blasts were positive for CD19/CD20/cytoplasmic CD79a/cytoplasmic CD22/CD13/CD71.The blasts were negative for T-lineage markers and myeloperoxidase (MPO). Induction chemotherapy with the standard regimen for B-ALL resulted in primary induction failure. After the second induction chemotherapy regimen, the blasts were found to be B/T bi-phenotypic with additional expression of cytoplasmic CD3. A single course of clofarabine (the fourth induction chemotherapy regimen) dramatically reduced lymphoid marker levels. However, the myeloid markers (e.g., MPO) eventually showed positivity and the leukemia completely changed its lineage to AML. Despite subsequent intensive chemotherapy regimens designed for AML, the patient’s leukemia was uncontrollable and a new monoblastic population emerged. The patient died approximately 8 months after the initial diagnosis without experiencing stable remission. Several cytogenetic and genetic features were commonly identified in the initial diagnostic B-ALL and in the following AML, suggesting that this case should be classified as lineage switching leukemia rather than multiple simultaneous cancers (i.e., de novo B-ALL and de novo AML, or primary B-ALL and therapy-related myeloid neoplasm). A complex karyotype was persistently observed with a hemi-allelic loss of chromosome 17 (the location of the TP53 tumor suppressor gene). As the leukemia progressed, the karyotype became more complex, with the additional abnormalities. Sequential target sequencing revealed an increased variant allele frequency of TP53 mutation. Fluorescent in situ hybridization (FISH) revealed an increased number of mixed-lineage leukemia (MLL) genes, both before and after lineage conversion. In contrast, FISH revealed negativity for MLL rearrangements, which are well-known abnormalities associated with lineage switching leukemia and MPAL. To our best knowledge, this is the first reported case of acute leukemia presenting with lineage ambiguity and MLL gene amplification.

Chronic neutrophilic leukemia (CNL) is a rare myeloproliferative neoplasm (MPN) characterized by sustained mature neutrophilic leukocytosis. Recently, presence of colony-stimulating factor 3 receptor (CSF3R) mutations has been added to the diagnostic criteria for CNL. Anti-inflammatory effects of the JAK1/2 inhibitor ruxolitinib relieve constitutional symptoms associated with MPN, such as fatigue, night sweats, and fever. We present a case of CNL harboring CSF3R-T618I mutation exacerbated by concomitant bilateral renal abscesses, which was refractory to antibiotics, at the time of initial diagnosis. In this case, ruxolitinib rapidly improved not only CNL but the infection, due to its anti-inflammatory potency.

Myelodysplastic syndrome (MDS) is a clonal disorder of hematopoietic stem cells (HSCs), characterized by ineffective hematopoiesis and frequent progression to leukemia. It has long remained unresolved how MDS cells, which are less proliferative, inhibit normal hematopoiesis and eventually dominate the bone marrow space. Despite several studies implicating mesenchymal stromal or stem cells (MSCs), a principal component of the HSC niche, in the inhibition of normal hematopoiesis, the molecular mechanisms underlying this process remain unclear. Here, we demonstrate that both human and mouse MDS cells perturb bone metabolism by suppressing the osteolineage differentiation of MSCs, which impairs the ability of MSCs to support normal HSCs. Enforced MSC differentiation rescues the suppressed normal hematopoiesis in both in vivo and in vitro MDS models. Intriguingly, the suppression effect is reversible and mediated by extra cellular vesicles (EVs) derived from MDS cells. These findings shed light on the novel MDS EV-MSC axis in ineffective hematopoiesis.

COVID-19 often contributes to thrombus formation in microvessels, resulting in damaged vital organs. In this study, we report a case of COVID-19 associated with acquired thrombotic thrombocytopenic purpura (TTP). A 44-year-old man with a history of systemic lupus erythematosus presented with COVID-19 and concomitant hemolytic anemia and a marked thrombocytopenia. The patient was diagnosed with acquired TTP because ADAMTS13 inhibitor was detected and ADAMTS13 activity below the sensitivity level. The patient developed agitated neuropsychiatric symptoms, such as aphasia, disorientation, and delirium, which improved after a plasma exchange, prednisolone, and rituximab administration. Only a few reports have revealed COVID-19 with TTP, and this is the first case in Japan. Although acquired TTP rarely develops, it is an important complication of COVID-19, and thus, it should be promptly diagnosed and treated as soon as possible.

An 88-year-old woman was diagnosed with multiple myeloma received third-line chemotherapy, including DBd (daratumumab [DARA], bortezomib, and dexamethasone [Dex]), and the myeloma was in remission. Sulfamethoxazole/trimethoprim (ST) prophylaxis was discontinued because the dose of Dex was reduced to 20 mg every 4 weeks after 21 cycles of DBd. After 28 cycles of DBd, altered consciousness with fever ensued, and she was referred to the emergency department where Listeria monocytogenes (LM) meningitis was diagnosed. CD38 inactivation is associated with increased LM susceptibility. In patients on Dara-based chemotherapy, antibiotic prophylaxis should be considered using ST, which has activity against Listeria.

A 50-year old man with a 1-year history of eosinophilia presented with an eosinophil count exceeding 13,800/mm3 in the peripheral blood at the first visit. Bone marrow examination revealed that eosinophils accounted for 30% of the nucleated cell count, and G-band karyotyping analysis detected t (5;14)(q33;q22). Using peripheral blood FISH test, he was found to have platelet-derived growth factor receptor β (PDGFRB) locus rearrangement at 5q32-33. The level of eosinophils in the peripheral blood reduced markedly 3 days after the initiation of Imatinib mesylate, 400 mg daily. This treatment was administered for 2 years, after which the peripheral blood FISH test was negative for PDGFRB. In this disease, although most cases are with t (5;12), those with t (5;14) are relatively rare, and the long-term course of this translocation is unknown.

A man in his early 70s visited a previous hospital because of pancytopenia and was diagnosed with acute myeloid leukemia based on a bone marrowexamination. The karyotype was 46,XY, t(9;22)(q34;q11.2)[2/20], and real-time polymerase chain reaction(PCR)revealed minor bcr-abl chimeric mRNA. Finally, the patient was judged as having Philadelphia chromosome- positive acute myeloid leukemia, and remission induction chemotherapy with the JALSG AML 201 protocol was initiated in combination with dasatinib to achieve complete remission. After 3 courses of consolidation chemotherapy, the anticancer drugs were discontinued because of deterioration of his general condition and renal insufficiency. Six months after the initial treatment, he was referred to our department, and no evidence of recurrence was confirmed on bone marrow examination. However, 2 months later, right massive pleural effusion was detected, and he was admitted to the department of pneumology at our hospital. Thoracoscopic pleural biopsy was performed at the time of chest tube insertion, and he was diagnosed with acute myeloid leukemia extramedullary recurrence. Peripheral myeloblasts appeared and increased rapidly, accompanied by further exacerbation of renal function; thus, he received palliative care at the department of hematology and oncology.

A man in his late teens presented to our hospital with left-sided chest pain. CT showed a 12 cm sized anterior mediastinal tumor and tiny nodules in the bilateral lower lobe of the lungs. The patient also had elevated serum AFP and hCG levels. Pathological findings of the CT-guided biopsy specimen suggested a yolk sac tumor, and no testicular abnormality was seen on ultrasound. Following whole body examination, he was diagnosed with primary mediastinal non-seminomatous germ cell tumor. After sperm cryopreservation, 4 courses of BEP(bleomycin[BLM]plus etoposide[ETP]plus cisplatin[CDDP]) chemotherapy were administered to normalize the tumor markers. The mediastinal tumor shrank but was still widely in contact with the left pulmonary artery. He underwent mediastinal tumor resection and segmentectomy of the left upper lobe via a median sternotomy. The maximum tumor size was 9 cm in diameter, and pathological examination of the specimen revealed only an immature teratoma with no malignant findings. At the same time, both the lower lung nodules were resected and pathologically identified as intrapulmonary lymph nodes. No recurrence was observed, but 6 months after surgery, he made an emergency visit to our department due to dyspnea. Bilateral pneumothorax was detected, and chest tube insertion was rapidly performed that improved with only right chest drainage. Cytology of the right hemorrhagic pleural effusion showed no evidence of malignancy. It was possible that a postoperative right-to-left shunt of the anterior mediastinum was present, leading to bilateral pneumothorax.

High-dose methotrexate therapy(HDMTX)is effective against lymphoid malignancies. However, delayed elimination of methotrexate(MTX)after HDMTX administration may lead to severe adverse drug reactions. We surveyed the drugs coadministered with MTX and the incidence of delayed MTX elimination in patients treated with HDMTX in a clinical setting. We analyzed the plasma MTX concentration in 110 samples after 55 cycles of HDMTX in 33 patients. Delayed MTX elimination was defined as a plasma MTX concentration ≥1.0 mmol/L at 48 h after the start of HDMTX administration or ≥0.1 mmol/L at 72 h after the start of HDMTX administration. The incidence of the combined use of drugs affecting MTX excretion and drugs that exhibited typical renal excretion was 84.8%(n=28). The incidence of delayed MTX elimination was 39.4%(n=13). MTX-induced acute kidney injury occurred in 9 patients, all of whom also exhibited delayed MTX elimination. Therefore, when prescribing HDMTX, it is important to monitor adverse events, including acute kidney injury, which may be induced by prolonged MTX blood concentrations.

Both adult T-cell leukemia/lymphoma (ATL) and human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) can be induced by HTLV-1, but concurrent development has been rarely reported. We present the case of a 55-year-old female who developed cranial nerve symptoms after a 20-year history of HAM/TSP. Although multiple white matter lesions were observed on brain magnetic resonance imaging, no abnormalities were seen on a systemic computed tomography scan. Quantitative flow-cytometric analysis of cell populations in the cerebrospinal fluid (CSF) revealed that most of the infiltrating cells were not inflammatory cells, but HTLV-1-infected CD4 + CADM-1 + T-cells completely lacking CD7 expression. As stepwise downregulation of CD7 is correlated with disease progression from HTLV-1 carrier to aggressive ATL, the CSF cells were classified as aggressive ATL; these cells exhibited a more progressed phenotype than those in peripheral blood (PB). HAM/TSP disease activity was estimated to be low. From these and other examinations, we made a diagnosis of acute-type ATL, which unusually developed in the central nervous system at initial onset prior to systemic progression. In ATL cases with a challenging diagnosis, immunophenotypic characterization of CSF and PB is valuable for differential diagnosis and understanding disease status.