Interim PET-guided ABVD or ABVD/escalated BEACOPP for newly diagnosed advanced-stage classic Hodgkin lymphoma (JCOG1305).

This single-arm confirmatory study (JCOG1305) aimed to evaluate the utility of interim positron emission tomography (iPET)-guided therapy for newly diagnosed advanced-stage classic Hodgkin lymphoma (cHL). Patients aged 16-60 years with cHL received two cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) and then underwent an iPET scan (PET2), which was centrally reviewed using a five-point Deauville scale. PET2-negative patients continued an additional four cycles of ABVD, whereas PET2-positive patients switched to six cycles of escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (eBEACOPP). The co-primary endpoints were 2-year progression-free survival (PFS) among all eligible and PET2-positive patients. Ninety-three patients were enrolled between January 2016 and December 2019. One patient was ineligible because of a diagnostic error. The median age of the 92 eligible patients was 35 (interquartile range, 28-48) years. Forty (43%) patients had stage III disease, and 43 (47%) had stage IV disease. The remaining nine (10%) patients had stage IIB disease with risk factors. Nineteen PET2-positive (21%) patients received eBEACOPP, 18 completed six cycles of eBEACOPP, 73 PET2-negative (79%) patients continued ABVD, and 70 completed an additional four cycles of ABVD. With a median follow-up period of 41.1 months, the 2-year PFS of 92 eligible patients and 19 PET2-positive patients were 84.8% (80% confidence interval [CI], 79.2-88.9) and 84.2% (80% CI, 69.7-92.1), respectively. Both primary endpoints were met at the prespecified threshold. This study demonstrates that iPET-guided therapy is a useful treatment option for younger patients with newly diagnosed advanced-stage cHL. Registration number: jRCTs031180218.

An update on the developments in the treatment of adult T-cell leukemia-lymphoma: current knowledge and future perspective.

Adult T-cell leukemia-lymphoma is defined as peripheral T-cell lymphoma caused by the human T-cell leukemia virus type I. Adult T-cell leukemia-lymphoma is classified into indolent (favorable chronic or smoldering) or aggressive (acute, lymphoma or unfavorable chronic) types. This review discusses the therapeutic developments for patients with adult T-cell leukemia-lymphoma and unmet issues in treating adult T-cell leukemia-lymphoma. For indolent adult T-cell leukemia-lymphoma, a watchful waiting strategy is recommended until the disease progresses to aggressive adult T-cell leukemia-lymphoma. For aggressive adult T-cell leukemia-lymphoma, multi-agent chemotherapy with or without allogeneic hematopoietic stem cell transplantation has been recommended. However, many patients with adult T-cell leukemia-lymphoma relapse, and their prognosis is poor. Recently, novel agents, including mogamulizumab, lenalidomide, brentuximab vedotin, tucidinostat and valemetostat, have been approved for patients with relapsed or refractory aggressive adult T-cell leukemia-lymphoma, and the combination of mogamulizumab with multi-agent chemotherapy or brentuximab vedotin with cyclophosphamide, doxorubicin and prednisone has been approved for patients with untreated aggressive adult T-cell leukemia-lymphoma in Japan. Importantly, the aging of patients with adult T-cell leukemia-lymphoma has recently been reported, and no standard of care for elderly patients with adult T-cell leukemia-lymphoma has been established. New evidence must be obtained from prospective clinical trials to improve the prognosis of patients with adult T-cell leukemia-lymphoma.

Dose-escalation part of Phase I study of single-agent mosunetuzumab in Japanese patients with relapsed/refractory B-cell non-Hodgkin lymphoma.

OBJECTIVE: This dose-escalation part of an ongoing Phase I study assessed the tolerability, safety and pharmacokinetics of mosunetuzumab in Japanese patients with relapsed/refractory B-cell non-Hodgkin lymphoma (NHL). METHODS: Mosunetuzumab was administered intravenously, with step-up dosing in a 3 + 3 design, on Days 1, 8 and 15 of Cycle 1, and Day 1 of each subsequent 21-day cycle for up to 17 cycles to patients across five cohorts with different target doses (2.8, 6.0, 13.5, 27.0 or 60.0 mg). RESULTS: As of 5 July 2022, 23 patients had received mosunetuzumab. The median patient age was 63.0 years, 56.5% of patients were male, and 69.6% of patients had diffuse large B-cell lymphoma, 17.4% had transformed follicular lymphoma (FL) and 13.0% had FL. The median number of prior lines of therapy was 4. Mosunetuzumab was well tolerated and there were no deaths. The most common adverse events (any grade) were neutropenia/neutrophil count decreased (47.8%) and cytokine release syndrome (34.8%). Most cytokine release syndrome events were Grade 1/2 (one Grade 3), and most occurred within 24 hours of the first dose of mosunetuzumab. The apparent half-life of mosunetuzumab was 4.1-5.0 days. Two patients achieved a complete response, and 11 patients achieved a partial response. CONCLUSIONS: This study demonstrated that mosunetuzumab has an acceptable safety profile and antitumor activity in Japanese patients with relapsed/refractory B-cell NHL. The recommended Phase II dose of 1.0/2.0/60.0/60.0/30.0 mg was tolerable and there were no new or different safety signals compared with the global Phase I study.

Two-year outcomes of tirabrutinib monotherapy in Waldenström's macroglobulinemia.

The phase II study of tirabrutinib monotherapy at a daily dose of 480 mg under fasting conditions for treatment-naïve and relapsed/refractory Waldenström's macroglobulinemia (ONO-4059-05 study) demonstrated a promising efficacy and tolerable safety profile. We conducted an unplanned analysis with a median follow-up of 24.8 months to update the efficacy and safety results and to report patient-reported quality of life. Of 27 enrolled patients, 22 patients continued receiving the study drug. The major response assessed by an independent review committee was observed in 25 patients (93%), including one and five patients who newly achieved complete response and very good partial response, respectively, after the primary analysis. The progression-free and overall survival rates at 24 months were 92.6% and 100%, respectively. Serum IgM levels in all patients except one declined and were maintained at low levels, although transient increases occurred after temporal interruption of the study drug. The disease-related symptoms including recurrent fever and hyperviscosity mostly disappeared. Health-related quality of life, assessed by cancer-specific questionnaires, was mostly maintained. Grade 3-4 neutropenia, lymphopenia, and leukopenia were newly recognized in three, two, and one patient, respectively. Grade 3 treatment-related hypertriglyceridemia was also recognized. Nine patients experienced grade 1-2 bleeding events (33%), one patient experienced grade 2 treatment-related atrial fibrillation, and one patient experienced grade 1 treatment-related hypertension. Treatment-related skin adverse events were observed in 14 patients (52%). Taken together, tirabrutinib has durable efficacy with an acceptable safety profile for treatment-naïve and refractory/relapsed Waldenström's macroglobulinemia.

Prognostic implication of CTLA-4, PD-1, and PD-L1 expression in aggressive adult T-cell leukemia-lymphoma.

The prognosis of patients with aggressive adult T cell leukemia-lymphoma (ATLL) is dismal even with intensive chemotherapy. Allogeneic hematopoietic stem cell transplantation (HSCT) is a promising option for patients with aggressive ATLL, but the posttransplant outcome remains unsatisfactory. Hence, to further improve clinical outcomes, novel therapeutic approaches are needed. The clinical significance of immune checkpoint protein expression has not been well-established in aggressive ATLL. This study aims to identify the association between the expression profile of immune checkpoint proteins on ATLL cells and clinical outcomes. This retrospective study cohort included 65 patients with aggressive ATLL diagnosed between 2001 and 2015 at the National Cancer Center Hospital, Tokyo, Japan. Formalin-fixed paraffin-embedded tissue was used to immunohistochemically determine the expression of immune checkpoint proteins and assess the impact of expression profile on the probability of overall survival from diagnosis or HSCT. The current analysis shows that cytotoxic T lymphocyte antigen-4 (CTLA-4), programmed death-1 (PD-1), and programmed death-ligand 1 (PD-L1) expressions were adverse prognostic factors in patients with aggressive ATLL. Experiments that assess the efficacy of immune checkpoint inhibitors are warranted to alleviate the adverse impacts associated with negative immune checkpoints.

Aberrant PD-L1 expression through 3'-UTR disruption in multiple cancers.

Successful treatment of many patients with advanced cancer using antibodies against programmed cell death 1 (PD-1; also known as PDCD1) and its ligand (PD-L1; also known as CD274) has highlighted the critical importance of PD-1/PD-L1-mediated immune escape in cancer development. However, the genetic basis for the immune escape has not been fully elucidated, with the exception of elevated PD-L1 expression by gene amplification and utilization of an ectopic promoter by translocation, as reported in Hodgkin and other B-cell lymphomas, as well as stomach adenocarcinoma. Here we show a unique genetic mechanism of immune escape caused by structural variations (SVs) commonly disrupting the 3' region of the PD-L1 gene. Widely affecting multiple common human cancer types, including adult T-cell leukaemia/lymphoma (27%), diffuse large B-cell lymphoma (8%), and stomach adenocarcinoma (2%), these SVs invariably lead to a marked elevation of aberrant PD-L1 transcripts that are stabilized by truncation of the 3'-untranslated region (UTR). Disruption of the Pd-l1 3'-UTR in mice enables immune evasion of EG7-OVA tumour cells with elevated Pd-l1 expression in vivo, which is effectively inhibited by Pd-1/Pd-l1 blockade, supporting the role of relevant SVs in clonal selection through immune evasion. Our findings not only unmask a novel regulatory mechanism of PD-L1 expression, but also suggest that PD-L1 3'-UTR disruption could serve as a genetic marker to identify cancers that actively evade anti-tumour immunity through PD-L1 overexpression.

Phase 1 study of tazemetostat in Japanese patients with relapsed or refractory B-cell lymphoma.

BACKGROUND: Tazemetostat is a selective and orally available inhibitor of enhancer of zeste homolog 2 (EZH2), a histone methyltransferase and epigenetic regulator of cellular differentiation programs. We carried out a phase I study of tazemetostat in Japanese patients with relapsed or refractory B-cell non-Hodgkin-type lymphoma (B-NHL) to evaluate its tolerability, safety, pharmacokinetics, and preliminary antitumor activity. METHODS: Tazemetostat was given orally at a single dose of 800 mg on the first day and 800 mg twice daily (BID: total 1600 mg/d) on following days in a 28-day/cycle manner. Tazemetostat dose-limiting toxicity (DLT) was evaluated up to the end of the first treatment cycle. Archival tumor tissues were analyzed for hotspot EZH2 mutations. RESULTS: As of 15 January 2018, seven patients (four follicular lymphoma [FL] and three diffuse large B-cell lymphoma [DLBCL]) were enrolled. The median age was 73 (range, 59-85) years, and the median number of prior chemotherapy regimens was three (range, one to five). No DLT was observed (one patient was not evaluable due to early disease progression). The common treatment-related adverse events (AEs) were thrombocytopenia and dysgeusia (three patients each; 42.9%). No treatment-related serious AEs were observed. The objective response rate was 57% (4/7 patients), including responses in three of four patients with FL and one of three patients with DLBCL. An EZH2 mutation was detected in one patient with FL responding to treatment. CONCLUSIONS: Tazemetostat at 800 mg BID showed an acceptable safety profile and promising antitumor activity in Japanese patients with relapsed or refractory B-NHL.

Clinicopathological factors and tumor microenvironment markers predicting watch-and-wait discontinuation in 82 patients with follicular lymphoma.

OBJECTIVES: In this study, we aimed to determine the clinicopathological factors influencing the treatment-free period in patients with follicular lymphoma (FL) using a watch-and-wait (WW) strategy. METHODS: We retrospectively assessed histopathological parameters of 82 patients with FL. RESULTS: The median time from diagnosis to WW discontinuation was 62 months (range, 3-138), and median follow-up was 86 months (range, 3-183). Intermediate or high-risk Follicular Lymphoma International Prognostic Index score (P = .012), non-duodenal-type (P = .011), higher numbers of interfollicular CD4+ (P = .038) and intrafollicular FOXP3+ cells (P = .024) in the tumor microenvironment, and Ki-67 index ≥10% (P = .031) were significant adverse factors for WW discontinuation in univariate analyses. CONCLUSION: Patients with adverse factors for WW discontinuation should be carefully observed during follow-up.

The role of local radiotherapy following rituximab-containing chemotherapy in patients with transformed indolent B-cell lymphoma.

OBJECTIVES: This study aimed to evaluate the outcomes of local radiotherapy (LRT) in patients with histologic transformation (HT) following rituximab-containing chemotherapy. METHODS: We retrospectively analysed 92 patients with biopsy-confirmed HT undergoing rituximab-containing chemotherapy at our institution between 2003 and 2015. RESULTS: Of the 36 patients with limited-stage disease at diagnosis of HT, 29 (78%) received LRT. The estimated 5-year progression-free survival (PFS) rate was significantly better in patients who underwent LRT than in those who did not (93% and 42%, respectively; P < 0.05). Multivariate analyses employing age, sex, performance status, LRT and treatment response demonstrated that LRT was an independent prognostic factor for PFS (hazard ratio [HR]: 11.8; 95% confidence interval [CI]: 1.28-108.1; P < 0.05). Of the 32 patients who underwent LRT for HT lesion treatment, 31 (97%) did not show disease progression within radiation fields; among them, 27 patients (84%) survived without disease progression during the follow-up period. One patient developed hypothyroidism due to LRT; the others had no acute or late-onset complications of LRT. CONCLUSIONS: Our data support the recommendation of LRT for HT lesion treatment following rituximab-containing chemotherapy in select patients with localised HT, as a rational treatment approach with potentially limited toxicity.

Use of Core-Needle Biopsy for the Diagnosis of Malignant Lymphomas in Clinical Practice.

INTRODUCTION: Excisional biopsy (EB) is considered the gold standard for lymphoma diagnosis. Although recent advances in interventional radiology enable sampling with core-needle biopsy (CNB), only few studies evaluated the utility of CNB compared to that of EB. METHODS: We analyzed patients with lymphoma who had a diagnostic biopsy at the National Cancer Center Hospital during 2002-2017. We investigated the clinical and pathological characteristics of CNB in 2017. RESULTS: The proportion of CNB utility in total biopsy procedures had increased from 11 to 48% during the 15 years. In 2017, CNB was opted more frequently than EB for a biopsy of superficial, abdominal, or anterior mediastinal lesions. Only one out of 72 patients who had CNB required re-biopsy with EB because of insufficiency. The incidence of complications was comparable between CNB and EB: 2 (4%) cases of minor bleeding with CNB and 1 (8%) case of minor bleeding with EB. The median time from the first visit to biopsy was significantly shorter with CNB (5.5 days) than with EB (15 days). CONCLUSION: There is an increasing trend in the utility of CNB. CNB is a less invasive method with shorter time to biopsy and can be considered an alternative to EB.

Single response assessment of transplant-ineligible multiple myeloma: a supplementary analysis of JCOG1105 (JCOG1105S1).

BACKGROUND: The International Myeloma Working Group response criteria require two consecutive assessments of paraprotein levels. We conducted an exploratory analysis to evaluate whether a single response assessment could be a substitute for the International Myeloma Working Group criteria using data from JCOG1105, a randomized phase II study on melphalan, prednisolone and bortezomib. METHODS: Of 91 patients with transplant-ineligible newly diagnosed multiple myeloma, 79 patients were included. We calculated the kappa coefficient to evaluate the degree of agreement between the International Myeloma Working Group criteria and the single response assessment. RESULTS: Based on the International Myeloma Working Group criteria, 11 (13.9%), 20 (25.3%), 36 (45.6%) and 12 (15.2%) patients had stringent complete response/complete response, very good partial response, partial response and stable disease, respectively. Based on the single response assessment, 17 (21.5%), 19 (24.1%), 35 (44.3%) and 8 (10.1%) patients had stringent complete response/complete response, very good partial response, partial response and stable disease, respectively. The kappa coefficient was 0.76 (95% confidence interval, 0.65-0.88), demonstrating good agreement. The single response assessment was not inferior to the International Myeloma Working Group criteria in the median progression-free survival (3.8 and 2.9 years) in stringent complete response/complete response patients, suggesting that the single response assessment was not an overestimation. CONCLUSIONS: The single response assessment could be a substitute for the current International Myeloma Working Group criteria for transplant-ineligible newly diagnosed multiple myeloma.

Usefulness of hematopoietic progenitor cell monitoring to predict autologous peripheral blood stem cell harvest timing: A single-center retrospective study.

INTRODUCTION: In autologous peripheral blood stem cell harvest (APBSCH), CD34-positive cells have been measured to assess the numbers of hematopoietic stem cells, but measurement requires specialized equipment. Recently, there was a report that peripheral blood hematopoietic progenitor cells (HPCs) are useful indicators of the presence of hematopoietic stem cells. We examined the usefulness of HPC monitoring to predict APBSCH timing. METHODS: We retrospectively analyzed the relationship between HPC and collected CD34-positive cells in 84 consecutive patients who underwent APBSCH. RESULTS: According to the receiver operating characteristics curve for the collection of ≥2 × 106 CD34-positive cells/kg, the HPC cut-off value on the day before collection was 21/µL, while that on the day of collection was 41/µL. No significant factors were found in the univariate analysis except for the HPC count on the day before collection (p < 0.001) and the day of collection (p < 0.001). According to the multivariate analysis, the HPC count on the day before collection (p < 0.001) and the day of collection (p < 0.001) were also factors that strongly influenced the quantity of CD34-positive cells collected. CONCLUSION: Our results suggest that the HPC count on not only the day of collection but also the day before collection is a good indicator for appropriate APBSCH timing.

Diagnostic utility and prognostic significance of the Ki-67 labeling index in diffuse large B-cell lymphoma transformed from follicular lymphoma: a study of 76 patients.

The diagnosis of histological transformation of follicular lymphoma can be challenging and ambiguous. We investigated the distribution of the Ki-67 labeling index of histological transformation of follicular lymphoma and determined its cutoff value to predict poor outcomes. The diagnostic criteria for histological transformation were a diffuse pattern of proliferation and a proportion of large lymphoma cells ≥20%. Of the 1121 patients with follicular lymphoma, 171 (15%) showed histological transformation to diffuse large B-cell lymphoma. Of these, 76 patients, whose biopsies were obtained from the sites with the highest maximum standardized uptake values, according to the positron emission tomography findings, were included. The Ki-67 index ranged from 16.8% to 98.4% (median, 60.6%). In patients with histological transformation, the most significant differences were found in progression-free survival (p = 0.087, 58% vs. 87% at 2 years) and overall survival (p = 0.024, 53% vs. 85% at 5 years) when a 70% cutoff was used. Additionally, overall survival was significantly shorter in patients with histological transformation with maximum standardized uptake values of ≥20 (p < 0.0001) and absence of a follicular lymphoma component (p = 0.004). A Ki-67 index of ≥70% was a significant adverse factor for overall survival in patients with histological transformation of follicular lymphoma and may predict poor outcomes.

[Development and prospects of molecular targeted agents for malignant lymphoma].

It has been 20 years since the clinical introduction of rituximab, a monoclonal anti-CD20 antibody. Rituximab combination chemotherapy has substantially improved the prognosis of nearly all B-cell malignancies. Twenty years following the clinical introduction of rituximab, the era of molecular targeted agents and development of novel molecular targeted agents, including monoclonal antibody based on the molecular pathology, has been promoted. In recent years, CAR-T therapy and immune checkpoint inhibitors have been introduced in the clinical practice of malignant lymphoma. On the other hand, there are many histopathological subtypes that cannot directly receive the benefits of immunotherapy, and sufficient improvement in the prognosis of these subtypes is not seen. Therefore, further elucidation of molecular pathology and development of novel molecular targeted agents are crucial for the improvement of their prognosis. In this review, molecular targeted agents introduced into clinical practice in recent years, which revolutionized the treatment of malignant lymphoma, and molecular targeted agents expected to be introduced in clinical practice in the near future are discussed.

[Current treatment strategies for peripheral T-cell lymphoma].

Peripheral T-cell lymphoma (PTCL) is a heterogeneous group of aggressive non-Hodgkin lymphomas (NHLs) with poor prognoses as compared with those of B-cell NHLs. CHOP or CHOP-like regimen has been considered to be the standard treatment for almost all pathological subtypes of PTCL; however, these regimens result in low complete response rate and short progression-free survival (PFS). Due to these insufficient results with CHOP-based chemotherapy, there is an urgent need for more effective and newer therapeutic strategies. The positive results of the ECHELON-2 study, which demonstrated significantly longer PFS with brentuximab vedotin plus CHP therapy in the frontline treatment for CD30-positive PTCLs, have a great impact on our clinical practice. At present, translational research is being actively conducted to elucidate molecular biology in PTCLs, and deep understanding of the underlying molecular mechanism of PTCLs would produce changes in disease classification. Until now, clinical development of novel agents based on the clinical classification has been carried out for all PTCL subtypes, but from now, treatment development based on molecular biology will be strongly required.

A multicenter, open-label, phase II study of tirabrutinib (ONO/GS-4059) in patients with Waldenström's macroglobulinemia.

Tirabrutinib is a second-generation Bruton's tyrosine kinase inhibitor with greater selectivity than ibrutinib. Here, we conducted a multicenter, phase II study of tirabrutinib in patients with treatment-naïve (Cohort A) or with relapsed/refractory (Cohort B) Waldenström's macroglobulinemia (WM). Patients were treated with tirabrutinib 480 mg once daily. The primary endpoint was major response rate (MRR; ≥ partial response). Secondary endpoints included overall response rate (ORR; ≥ minor response), time to major response (TTMR), progression-free survival (PFS), overall survival (OS), and safety. In total, 27 patients (18 in Cohort A; 9 in Cohort B) were enrolled. The median age was 71 y, and the median serum immunoglobulin M level was 3600 mg/dL. Among the patients, 96.2% had the MYD88L265P mutation. MRR and ORR were 88.9% and 96.3%, respectively (Cohort A: MRR, 88.9%; ORR, 94.4%; Cohort B: MRR, 88.9%; ORR, 100%). Median TTMR was 1.87 mo. PFS and OS were not reached with a median follow-up of 6.5 and 8.3 mo for Cohorts A and B, respectively. The most common adverse events (AEs) were rash (44.4%), neutropenia (25.9%), and leukopenia (22.2%), with most AEs classified as grade 1 or 2. Grade ≥ 3 AEs included neutropenia (11.1%), lymphopenia (11.1%), and leukopenia (7.4%). No grade 5 AEs were noted. All bleeding events were grade 1; none were associated with drug-related atrial fibrillation or hypertension. Although the follow-up duration was relatively short, the study met the primary endpoint. Therefore, tirabrutinib monotherapy is considered to be highly effective for both untreated and relapsed/refractory WM with a manageable safety profile. (JapicCTI-173646).

Prognostic relevance of integrated genetic profiling in adult T-cell leukemia/lymphoma.

Adult T-cell leukemia/lymphoma (ATL) is a heterogeneous group of peripheral T-cell malignancies characterized by human T-cell leukemia virus type-1 infection, whose genetic profile has recently been fully investigated. However, it is still poorly understood how these alterations affect clinical features and prognosis. We investigated the effects of genetic alterations commonly found in ATL on disease phenotypes and clinical outcomes, based on genotyping data obtained from 414 and 463 ATL patients using targeted-capture sequencing and single nucleotide polymorphism array karyotyping, respectively. Aggressive (acute/lymphoma) subtypes were associated with an increased burden of genetic and epigenetic alterations, higher frequencies of TP53 and IRF4 mutations, and many copy number alterations (CNAs), including PD-L1 amplifications and CDKN2A deletions, compared with indolent (chronic/smoldering) subtypes. By contrast, STAT3 mutations were more characteristic of indolent ATL. Higher numbers of somatic mutations and CNAs significantly correlated with worse survival. In a multivariate analysis incorporating both clinical factors and genetic alterations, the Japan Clinical Oncology Group prognostic index high-risk, older age, PRKCB mutations, and PD-L1 amplifications were independent poor prognostic factors in aggressive ATL. In indolent ATL, IRF4 mutations, PD-L1 amplifications, and CDKN2A deletions were significantly associated with shorter survival, although the chronic subtype with unfavorable clinical factors was only marginally significant. Thus, somatic alterations characterizing aggressive diseases predict worse prognosis in indolent ATL, among which PD-L1 amplifications are a strong genetic predictor in both aggressive and indolent ATL. ATL subtypes are further classified into molecularly distinct subsets with different prognosis. Genetic profiling might contribute to improved prognostication and management of ATL patients.

Immunohistochemical CD20-negative change in B-cell non-Hodgkin lymphomas after rituximab-containing therapy.

CD20- change after rituximab-containing therapy is considered one of the main reasons of rituximab resistance of B-cell non-Hodgkin lymphomas (B-NHLs). However, the clinicopathological characteristics of B-NHL with CD20- change are not entirely understood. In this study, 252 B-NHL patients who were CD20+ at initial diagnosis, whose diseases relapsed or were refractory after rituximab-containing therapy, and who were re-biopsied between 2000 and 2018, were included. The median number of rituximab administration was 11 (range, 1-48). Completely negative (cCD20-) and partially negative (pCD20-) change of CD20 was observed in 49 (20%) and 16 (6%) cases, respectively. Among cCD20- and pCD20- cases, 74% and 62% of the cases changed to CD20- at the second relapse or later, respectively. Overall survival was significantly shorter in cCD20- follicular lymphoma (FL) cases than in CD20+ FL cases. Seven histopathological patterns, such as CD20- change without histological change, histological transformation (HT) to CD20- diffuse large B-cell lymphoma, and proliferation of plasmablastic/plasmacytoid tumor cells, were associated with CD20- change. HT occurred more frequently in FLs with CD20- change than in FLs continuously expressing CD20 (P < 0.0001), regardless of the timing of HT. Nine out of 25 cases (36%) showed regain or heterogeneous regain of CD20 expression. In conclusion, 20% and 6% of the 252 B-NHL cases show cCD20- and pCD20- changes with 7 histological patterns after rituximab-containing therapy. Because changes in morphology and CD20 expression after rituximab-containing therapy vary, and recovery of CD20 expression is not rare, careful follow-up and re-biopsy in B-NHL patients are recommended.

[A Case of Erdheim-Chester Disease that was Difficult to Differentiate from Meningioma].

OBJECTIVE: Erdheim-Chester disease(ECD)is a rare type of non-Langerhans histiocytosis. We report a surgical case of ECD with multiple lesions at the falx cerebri, tentorium cerebelli, and in the suprasellar region, with a literature review. CASE REPORT: A 70-year-old woman presented with frequent falling and difficulty in standing. Her past medical history revealed ovarian cystectomy, transient thrombocytopenia, hypertension, left lower leg pain, and overactive bladder. Her head CT and MRI findings revealed well-defined mass lesions, suspected of meningioma, at the falx cerebri and tentorium cerebelli. Craniotomy and near total resection of the tumor at the falx cerebri was performed, leaving a hard portion of the tumor on the right falx. Intraoperative findings showed a solid and hard tumor, which was extremely difficult to decompress. Although the histopathological diagnosis was originally a metaplastic meningioma, considering her complaints of lower leg pain, we suspected ECD and performed a right tibial biopsy. The right tibial biopsy revealed ECD. Twenty-two months after the operation, the patient exhibited a marked enlargement of the tentorium lesion and a new lesion in the suprasellar region. Resection of the tentorial lesion was performed. The second intraoperative findings were similar to those of the first. The histopathological diagnosis of the tentorial lesion was ECD. After the surgeries, steroid therapy and radiation therapy were performed, but only with temporary improvement. CONCLUSION: ECD is a rare disease; therefore, accumulation of clinical data to establish its treatment is necessary.

Phase I study of tirabrutinib (ONO-4059/GS-4059) in patients with relapsed or refractory B-cell malignancies in Japan.

We evaluated the safety, efficacy, pharmacokinetics, pharmacodynamics and predictive biomarkers of tirabrutinib, a second-generation, enhanced-selectivity Bruton's tyrosine kinase inhibitor in Japanese patients with relapsed/refractory B-cell non-Hodgkin lymphoma (B-cell NHL) and chronic lymphocytic leukemia (CLL). This was an open-label, multicenter, phase I study. Seventeen patients (male N = 8) with a median age of 70 years were enrolled in 4 dose cohorts (160 mg once daily [N = 3], 320 mg once daily [N = 3], 480 mg once daily [N = 4] and 300 mg twice daily [N = 7]); 4 patients had continued tirabrutinib administration as of 4 January 2018. The maximum tolerated dose was not reached. Pneumonitis (N = 1) was the dose-limiting toxicity for 300 mg twice daily. Common adverse events (AEs) were rash (35.3%) and vomiting (29.4%). Eight patients (47.1%) developed grade ≥3 AEs: neutropenia (23.5%), anemia (11.8%) and leukopenia (11.8%) were frequent. The overall response rate (≥PR) was 76.5% (13/17 patients), including 4 DLBCL patients with no CD79A/B or MYD88 mutations, and 1 CLL patient with a TP53 mutation, providing promising data for future developments. Of 16 patients with measurable lesions during the screening period, 12 showed ≥50% reductions in tumor diameter. In many patients, the tumor size decreased soon after beginning treatment. The maximum serum concentration for tirabrutinib was 611, 1220, 1280 and 886 ng/mL on Day 1 and 484, 971 1940, and 961 ng/mL on Day 28 for Cohorts 1-4, respectively. Tirabrutinib pharmacokinetics were linear, with little accumulation following multiple doses. Tirabrutinib was well tolerated and showed promising efficacy for B-cell NHL/CLL.