Extranodal NK/T-cell lymphoma with localized relapse in bone marrow of lower leg detected using PET-CT.

Extranodal natural killer (NK)/T-cell lymphoma (ENKTL) is a rare subtype of non-Hodgkin lymphoma (NHL) with poor prognosis, particularly in relapsed or refractory patients. Thus, timely detection of relapse and appropriate disease management are crucial. We present two patients with ENKTL, wherein positron emission tomography-computed tomography (PET-CT) with total-body coverage after induction therapy, detected newly relapsed regions in the bone marrow of the lower leg prior to progression. Case 1: A 47-year-old woman with nasal obstruction, showing 18F-fluoro-deoxyglucose (FDG) uptake in the nasal cavity (Lugano stage IE). After induction therapy (RT-2/3 DeVIC), PET-CT revealed abnormal uptake only in the right fibula. Case 2: A 68-year-old man with a skin nodule/ulcer and an enlarged right inguinal lymph node was diagnosed with advanced ENKTL. A PET-CT scan revealed abnormal uptake in the subcutaneous mass of the right medial thigh, lymph nodes, and descending colon (Lugano stage IV). After induction therapy, PET-CT revealed new abnormal uptake only in the left tibia. In both patients, CT-guided biopsy confirmed ENKTL recurrence. Moreover, PET-CT with whole-body coverage was useful for the timely assessment of relapse and detection of asymptomatic bone involvement. This approach allowed for modifications to treatment strategies in certain patients.

Vulnerability to APOBEC3G linked to the pathogenicity of deltaretroviruses.

Human retroviruses are derived from simian ones through cross-species transmission. These retroviruses are associated with little pathogenicity in their natural hosts, but in humans, HIV causes AIDS, and human T-cell leukemia virus type 1 (HTLV-1) induces adult T-cell leukemia-lymphoma (ATL). We analyzed the proviral sequences of HTLV-1, HTLV-2, and simian T-cell leukemia virus type 1 (STLV-1) from Japanese macaques (Macaca fuscata) and found that APOBEC3G (A3G) frequently generates G-to-A mutations in the HTLV-1 provirus, whereas such mutations are rare in the HTLV-2 and STLV-1 proviruses. Therefore, we investigated the mechanism of how HTLV-2 is resistant to human A3G (hA3G). HTLV-1, HTLV-2, and STLV-1 encode the so-called antisense proteins, HTLV-1 bZIP factor (HBZ), Antisense protein of HTLV-2 (APH-2), and STLV-1 bZIP factor (SBZ), respectively. APH-2 efficiently inhibits the deaminase activity of both hA3G and simian A3G (sA3G). HBZ and SBZ strongly suppress sA3G activity but only weakly inhibit hA3G, suggesting that HTLV-1 is incompletely adapted to humans. Unexpectedly, hA3G augments the activation of the transforming growth factor (TGF)-ß/Smad pathway by HBZ, and this activation is associated with ATL cell proliferation by up-regulating BATF3/IRF4 and MYC. In contrast, the combination of APH-2 and hA3G, or the combination of SBZ and sA3G, does not enhance the TGF-ß/Smad pathway. Thus, HTLV-1 is vulnerable to hA3G but utilizes it to promote the proliferation of infected cells via the activation of the TGF-ß/Smad pathway. Antisense factors in each virus, differently adapted to control host cellular functions through A3G, seem to dictate the pathogenesis.

A Rare Case of Adult Poorly Differentiated Chordoma of the Skull Base With Rapid Progression and Systemic Metastasis: A Review of the Literature.

Chordoma is a rare tumor that arises from chordal tissue during fetal life. Recently, the concept of poorly differentiated chordoma, a subtype of chordoma characterized by loss of SMARCB1/INI1 with a poorer prognosis than conventional chordomas, was established. It predominantly occurs in children and is rare in adults. Here, we report a rare adult case of poorly differentiated chordoma of the skull base with a unique course that rapidly systemically metastasized and had the shortest survival time of any adult chordoma reported to date. The patient was a 32-year-old male with a chief complaint of diplopia. MRI showed a widespread neoplastic lesion with the clivus as the main locus. Endoscopic extended transsphenoidal tumor resection was performed. Pathological findings showed that the tumor was malignant, and immunohistochemistry revealed a Ki-67 labeling index of 80%, diffusely positive brachyury, and loss of INI1 expression. The final diagnosis was poorly differentiated chordoma. Postoperatively, the residual tumor in the right cavernous sinus showed rapid growth. The patient was promptly treated with gamma knife three fractions. The residual tumor regressed, but the tumor developed systemic metastasis in a short period, and the patient died seven months after diagnosis. This report of a rapidly progressing and fatal adult poorly differentiated chordoma shows the highest Ki-67 labeling index reported to date. Prompt multidisciplinary treatment should be considered when the Ki-67 labeling index is high.

Anti-HTLV-1 immunity combined with proviral load as predictive biomarkers for adult T-cell leukemia-lymphoma.

Human T-cell leukemia virus type 1 (HTLV-1) establishes chronic infection in humans and induces a T-cell malignancy called adult T-cell leukemia-lymphoma (ATL) and several inflammatory diseases such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Persistent HTLV-1 infection is established under the pressure of host immunity, and therefore the immune response against HTLV-1 is thought to reflect the status of the disease it causes. Indeed, it is known that cellular immunity against viral antigens is suppressed in ATL patients compared to HAM/TSP patients. In this study, we show that profiling the humoral immunity to several HTLV-1 antigens, such as Gag, Env, and Tax, and measuring proviral load are useful tools for classifying disease status and predicting disease development. Using targeted sequencing, we found that several carriers whom this profiling method predicted to be at high risk for developing ATL indeed harbored driver mutations of ATL. The clonality of HTLV-1-infected cells in those carriers was still polyclonal; it is consistent with an early stage of leukemogenesis. Furthermore, this study revealed significance of anti-Gag proteins to predict high risk group in HTLV-1 carriers. Consistent with this finding, anti-Gag cytotoxic T lymphocytes (CTLs) were increased in patients who received hematopoietic stem cell transplantation and achieved remission state, indicating the significance of anti-Gag CTLs for disease control. Our findings suggest that our strategy that combines anti-HTLV-1 antibodies and proviral load may be useful for prediction of the development of HTLV-1-associated diseases.

Dose Individualization of Cefepime for Febrile Neutropenia in Patients With Lymphoma or Multiple Myeloma: Implications for Therapeutic Drug Monitoring.

BACKGROUND: Optimal cefepime dosing is a challenge because of its dose-dependent neurotoxicity. This study aimed to determine individualized cefepime dosing for febrile neutropenia in patients with lymphoma or multiple myeloma. METHODS: This prospective study enrolled 16 patients receiving cefepime at a dose of 2 g every 12 hours. Unbound concentrations were determined at 0.5 hours, 7.2 hours [at the 60% time point of the 12 hours administration interval (C7.2h)], and 11 hours (trough concentration) after the first infusion (rate: 2 g/h). The primary and secondary end points were the predictive performance of the area under the unbound concentration-time curve (AUC unbound ) and the effect of unbound cefepime pharmacokinetic parameters on clinical response, respectively. RESULTS: The mean (SD) AUC unbound was 689.7 (226.6) mcg h/mL, which correlated with C7.2h (R 2 = 0.90), and the Bayesian posterior AUC unbound using only the trough concentration (R 2 = 0.66). Although higher exposure was more likely to show a better clinical response, each parameter did not indicate a statistical significance between positive and negative clinical responses ( P = 0.0907 for creatinine clearance (Ccr), 0.2523 for C7.2h, 0.4079 for trough concentration, and 0.1142 for AUC unbound ). Cutoff values were calculated as 80.2 mL/min for Ccr (sensitivity: 0.889, specificity: 0.714), 18.6 mcg/mL for C7.2h (sensitivity: 0.571, specificity: 1.000), and 9.2 mcg/mL for trough concentration (sensitivity: 0.571, specificity: 1.000). When aiming for a time above 100% the minimum inhibitory concentration, both continuous infusion of 4 g/d and intermittent infusion of 2 g every 8 hours achieved a probability of approximately 100% at a minimum inhibitory concentration of 8 mcg/mL. CONCLUSIONS: Therapeutic drug monitoring by sampling at C7.2h or trough can facilitate rapid dose optimization. Continuous infusion of 4 g/d was recommended. Intermittent dosing of 2 g every 8 hours was alternatively suggested for patients with a Ccr of 60-90 mL/min.

Performance evaluation of Espline HTLV-I/II, a newly developed rapid immunochromatographic antibody test for different diagnostic situations.

IMPORTANCE: The World Health Organization estimated that 5-10 million people are infected with human T-cell leukemia virus type 1 (HTLV-1). This number is likely to be underestimated because reliable endemic data are available for only approximately 1.5 billion people worldwide. The point-of-care test is a powerful tool for the easy and quick detection of infections without the requirement for expensive instruments and laboratory equipment. Espline HTLV-I/II, a newly developed rapid immunochromatographic antibody test that was evaluated in this study, might significantly advance our understanding of the global epidemiology of HTLV-1 infection.

Waldenstrom's macroglobulinemia-like B cell lymphoma with MYD88 L265P mutation and t(14;18)(q32;q21) involving IGH-MALT1.

A 65-year-old woman was referred to the hospital for further investigation of weight loss, hyperproteinemia, and anemia. Serum immunofixation electrophoresis revealed IgM-κ M protein. Bone marrow examination revealed an increase in the number of B -cells with immunoglobulin kappa light-chain restriction. Although the MYD88 L265P mutation was identified in bone marrow mononuclear cells, which suggested the diagnosis of Waldenstrom's macroglobulinemia (WM), a fusion signal of IgH-MALT1, which is commonly observed in extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) lymphoma, was also identified. Here, we describe a rare case of low-grade B-cell lymphoma with MYD88 L265P mutations accompanying IgH-MALT1.

Long-term follow-up after R-High CHOP/CHASER/LEED with Auto-PBSCT in untreated mantle cell lymphoma-Final analysis of JCOG0406.

Progression-free survival after R-High CHOP/CHASER/LEED with auto-PBSCT in untreated mantle cell lymphoma in JCOG0406 study. A continuous pattern of relapse was observed.

Lynch syndrome-associated chordoma with high tumor mutational burden and significant response to immune checkpoint inhibitors.

Chordoma is a rare malignant bone tumor arising from notochordal tissue. Conventional treatments, such as radical resection and high-dose irradiation, frequently fail to control the tumor, resulting in recurrence and re-growth. In this study, genetic analysis of the tumor in a 72-year-old male patient with refractory conventional chordoma of the skull base revealed a high tumor mutational burden (TMB) and mutations in the MSH6 and MLH1 genes, which are found in Lynch syndrome. The patient and his family had a dense cancer history, and subsequent germline genetic testing revealed Lynch syndrome. This is the first report of a chordoma that has been genetically proven to be Lynch syndrome. Chordomas usually have low TMB; however, this is an unusual case, because the TMB was high, and immune checkpoint inhibitors effectively controlled the tumor. This case provides a basis for determining the indications for immunotherapy of chordoma based on the genetic analysis. Therefore, further extensive genetic analysis in the future will help to stratify the treatment of chordoma.

Integrated genetic and clinical prognostic factors for aggressive adult T-cell leukemia/lymphoma.

The prognosis of aggressive adult T-cell leukemia/lymphoma (ATL) is poor, and allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative treatment. In order to identify favorable prognostic patients after intensive chemotherapy, and who therefore might not require upfront allo-HSCT, we aimed to improve risk stratification of aggressive ATL patients aged <70 years. The clinical risk factors and genetic mutations were incorporated into risk modeling for overall survival (OS). We generated the m7-ATLPI, a clinicogenetic risk model for OS, that included the ATL prognostic index (PI) (ATL-PI) risk category, and non-silent mutations in seven genes, namely TP53, IRF4, RHOA, PRKCB, CARD11, CCR7, and GATA3. In the training cohort of 99 patients, the m7-ATLPI identified a low-, intermediate-, and highrisk group with 2-year OS of 100%, 43%, and 19%, respectively (hazard ratio [HR] =5.46; P<0.0001). The m7-ATLPI achieved superior risk stratification compared to the current ATL-PI (C-index 0.92 vs. 0.85, respectively). In the validation cohort of 84 patients, the m7-ATLPI defined low-, intermediate-, and high-risk groups with a 2-year OS of 81%, 30%, and 0%, respectively (HR=2.33; P=0.0094), and the model again outperformed the ATL-PI (C-index 0.72 vs. 0.70, respectively). The simplified m7-ATLPI, which is easier to use in clinical practice, achieved superior risk stratification compared to the ATLPI, as did the original m7-ATLPI; the simplified version was calculated by summing the following: high-risk ATL-PI category (+10), low-risk ATL-PI category (-4), and non-silent mutations in TP53 (+4), IRF4 (+3), RHOA (+1), PRKCB (+1), CARD11 (+0.5), CCR7 (-2), and GATA3 (-3).

Validation of the iATL-PI prognostic index in therapeutic decision-making for patients with smoldering and chronic ATL: a multicenter study.

Adult T cell leukemia-lymphoma (ATL) is clinically heterogeneous and is classified into four subtypes: acute, lymphoma, chronic, and smoldering. Recently, a new prognostic index based on the value of soluble interleukin-2 receptor, denoted the "iATL-PI," has been proposed for patients with smoldering and chronic ATL. To evaluate the effectiveness of the iATL-PI, we re-analyzed our previously published data on 176 patients with smoldering or chronic ATL (76 smoldering, 100 chronic) diagnosed between 2010 and 2011, as well data from the subsequent follow-up study on prognosis between 2016 and 2017. The proportions for the low-, intermediate-, and high-risk iATL-PI groups at the time of ATL diagnosis were 44.7%, 48.7%, and 5% for smoldering ATL; 6.3%, 71.9%, and 21.9% for favorable chronic ATL; and 5.9%, 27.9%, and 66.2% for unfavorable chronic ATL, respectively. The survival of patients with smoldering or chronic ATL as a whole was significantly stratified according to the three iATL-PI groups. Most patients with unfavorable chronic ATL in the low iATL-PI risk group had indolent clinical courses. Our results showed that iATL may become a useful tool to predict the prognosis of smoldering and chronic ATL, which have diverse clinical courses.

An open-label, single-arm phase 2 trial of valemetostat for relapsed or refractory adult T-cell leukemia/lymphoma.

Adult T-cell leukemia/lymphoma (ATL) is an aggressive non-Hodgkin lymphoma with poor prognosis and few treatment options for patients with relapsed, recurrent, or refractory disease. We evaluated the efficacy and safety of valemetostat, a potent enhancer of zeste homolog 2 (EZH2) and EZH1 inhibitor, in treating relapsed or refractory (R/R) ATL. This multicenter phase 2 trial enrolled patients with R/R aggressive ATL (acute, lymphoma, unfavorable chronic type). Patients received valemetostat 200 mg/day orally until progressive disease or unacceptable toxicity. The primary end point was overall response rate (ORR) centrally assessed by an independent efficacy assessment committee (IEAC). Secondary end points included best response in disease compartments, duration of response (DOR), pharmacokinetics, and safety. Twenty-five patients (median age, 69.0 years) with a median of 3 prior lines of therapy were enrolled; 24 had prior mogamulizumab treatment. The primary end point was met with a centrally reviewed ORR of 48.0% (90% confidence interval [CI], 30.5-65.9), including 5 complete and 7 partial remissions. Patients pretreated with mogamulizumab had an ORR of 45.8% (4 complete and 7 partial remissions). IEAC-assessed median DOR was not reached (NR) (95% CI, 1.87 to NR; months). Treatment-emergent adverse events (TEAEs) were manageable. TEAEs that occurred in ≥20% of patients included thrombocytopenia, anemia, alopecia, dysgeusia, neutropenia, lymphopenia, leukopenia, decreased appetite, and pyrexia. Grade ≥3 TEAEs included thrombocytopenia, anemia, lymphopenia, leukopenia, and neutropenia. Valemetostat demonstrated promising efficacy and tolerability in heavily pretreated patients, warranting further investigation in treating R/R ATL. This trial was registered at www.clinicaltrials.gov as #NCT04102150.

[Follicular T-cell lymphoma successfully treated with long-term corticosteroid].

Follicular T-cell lymphoma (FTCL) is a rare disease, recently defined in the revised WHO classification Tumours of Haematopoietic and lymphoid tissues (4th edition). Although angioimmunoblastic T-cell lymphoma (AITL) and FTCL share similar T follicular helper (TFH) cell immunophenotypes and gene mutations, the clinical course of FTCL is not well characterized. Herein, we report the case of a 91-year-old woman with FTCL, who was successfully treated with corticosteroid. The patient, who had systemic lymphadenopathy and splenomegaly, was first diagnosed with necrotizing lymphadenitis. Re-biopsy was performed because of her persistent lymphadenopathy, which revealed FTCL. She was treated with corticosteroid because of her advanced age, poor performance, edema, and pleural effusion. After administering 100 mg prednisone, her condition improved and was discharged with prednisone tapering. Six-month positron emission tomography-computed tomography (PET-CT) scan showed complete metabolic remission. With a low dose of prednisone (6-10 mg), she remained disease-free for >3 years. Thus, these findings suggest that corticosteroid treatment is effective in some patients with peripheral T-cell lymphoma of TFH origin, including FTCL.

Predictive impact of soluble interleukin-2 receptor and number of extranodal sites for identification of patients at very high risk of CNS relapse in diffuse large B-cell lymphoma.

There remains an unmet clinical need to identify which patients with diffuse large B-cell lymphoma (DLBCL) would benefit from central nervous system (CNS) prophylaxis, due to the low positive predictive value (PPV; 10%-15%) of the currently available predictive models. To stratify patients at high risk of developing CNS relapse, we retrospectively analyzed 182 patients with DLBCL initially treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP), or a R-CHOP-like regimen. Among them, 17 patients relapsed with CNS involvement, and the 2-year rate of CNS relapse was 7.9%. Upon carrying out multivariate analysis, ≥3 extranodal sites and elevated soluble interleukin-2 receptor (sIL-2R) levels at diagnosis were identified as independent risk factors for CNS relapse. The 2-year and 3.5-year rates of CNS relapse were 57.1% and 78.6%, respectively, in patients with both elevated sIL-2R and ≥3 extranodal sites. Furthermore, combined use of these risk factors of both elevated sIL-2R and ≥3 extranodal sites resulted in a high PPV (71.4%), negative predictive value (93.1%), and overall accuracy (92.3%) for undergoing CNS relapse. In conclusion, we propose a simple and valuable tool to predict patients with DLBCL at very high risk of CNS relapse.

Identification and characterization of a novel enhancer in the HTLV-1 proviral genome.

Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus that causes adult T-cell leukemia/lymphoma (ATL), a cancer of infected CD4+ T-cells. There is both sense and antisense transcription from the integrated provirus. Sense transcription tends to be suppressed, but antisense transcription is constitutively active. Various efforts have been made to elucidate the regulatory mechanism of HTLV-1 provirus for several decades; however, it remains unknown how HTLV-1 antisense transcription is maintained. Here, using proviral DNA-capture sequencing, we found a previously unidentified viral enhancer in the middle of the HTLV-1 provirus. The transcription factors, SRF and ELK-1, play a pivotal role in the activity of this enhancer. Aberrant transcription of genes in the proximity of integration sites was observed in freshly isolated ATL cells. This finding resolves certain long-standing questions concerning HTLV-1 persistence and pathogenesis. We anticipate that the DNA-capture-seq approach can be applied to analyze the regulatory mechanisms of other oncogenic viruses integrated into the host cellular genome.