To Transplant or Not to Transplant During the SARS-CoV-2 Pandemic? That Is the Question.

The novel coronavirus disease 2019 has grown to be a global public health emergency. The rapid spread of the infection has raised many questions in the oncohematological scientific community regarding the appropriateness of high-dose chemotherapy with autologous stem cell transplantation (ASCT). We here report two cases of patients who received ASCT at our Institute during the epidemic in Italy, affected with Hodgkin lymphoma and germ cell tumor, respectively. The two patients underwent a nasopharyngeal swab for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on hospital admittance and during the period of bone marrow aplasia. They were attended to exclusively by dedicated health care staff who followed specifically implemented protocols for bedside nursing and care. They completed the procedure without unexpected side effect. Our experience demonstrates how ASCT can be performed safely if procedures are reorganized ad hoc to reduce the risk of SARS-CoV-2 infection.

A Comparison of the Conditioning Regimens BEAM and FEAM for Autologous Hematopoietic Stem Cell Transplantation in Lymphoma: An Observational Study on 1038 Patients From Fondazione Italiana Linfomi.

BEAM (carmustine [bis-chloroethylnitrosourea (BCNU)]-etoposide-cytarabine-melphalan) chemotherapy is the standard conditioning regimen for autologous stem cell transplantation (ASCT) in lymphomas. Owing to BCNU shortages, many centers switched to fotemustine-substituted BEAM (FEAM), lacking proof of equivalence. We conducted a retrospective cohort study in 18 Italian centers to compare the safety and efficacy of BEAM and FEAM regimens for ASCT in lymphomas performed from 2008 to 2015. We enrolled 1038 patients (BEAM = 607, FEAM = 431), of which 27% had Hodgkin lymphoma (HL), 14% indolent non-Hodgkin lymphoma (NHL), and 59% aggressive NHL. Baseline characteristics including age, sex, stage, B-symptoms, extranodal involvement, previous treatments, response before ASCT, and overall conditioning intensity were well balanced between BEAM and FEAM; notable exceptions were median ASCT year (BEAM = 2011 versus FEAM = 2013, P < .001), Sorror score ≥3 (BEAM = 15% versus FEAM = 10%, P = .017), and radiotherapy use (BEAM = 18% versus FEAM = 10%, P < .001). FEAM conditioning resulted in higher rates of gastrointestinal and infectious toxicities, including severe oral mucositis grade ≥3 (BEAM = 31% versus FEAM = 44%, P < .001), and sepsis from Gram-negative bacteria (mean isolates/patient: BEAM = .1 versus FEAM = .19, P < .001). Response status at day 100 post-ASCT (overall response: BEAM = 91% versus FEAM = 88%, P = .42), 2-year overall survival (83.9%; 95% confidence interval [CI], 81.5% to 86.1%) and progression-free survival (70.3%; 95% CI, 67.4% to 73.1%) were not different in the two groups. Mortality from infection was higher in the FEAM group (subhazard ratio, 1.99; 95% CI, 1.02 to 3.88; P = .04). BEAM and FEAM do not appear different in terms of survival and disease control. However, due to concerns of higher toxicity, fotemustine substitution in BEAM does not seem justified, if not for easier supply.

Clinical significance of LAIR1 (CD305) as assessed by flow cytometry in a prospective series of patients with chronic lymphocytic leukemia.

Most patients affected by chronic lymphocytic leukemia are diagnosed by flow cytometry. Several immunophenotypic markers have been identified as significant and independent prognostic variables, especially from retrospective cohorts. However, while attractive because their detection is inexpensive and feasible in most laboratories, only few have been validated by independent series. The expression of leukocyte-associated immunoglobulin-like receptor-1 (also known as LAIR1, LAIR-1 or CD305), an inhibitor of B-cell receptor-mediated signaling, has been reported to be lacking in high-risk chronic lymphocytic leukemia. However, its correlation with biological variables and its prognostic significance remain unknown. We investigated 311 consecutive patients, prospectively enrolled since 2007. Methods for studying patients were standardized and included clinical assessment, immunophenotype, fluorescence in situ hybridization, and status of immunoglobulin heavy chain variable region genes. Overall, 22.1% of patients had Binet stage B or C disease, 38.5% had unmutated immunoglobulin genes, 15.1% had high-risk cytogenetic abnormalities, 23.4% were CD38(+), 37.8% CD49d(+), and 59.8% LAIR1(+). Expression of LAIR1 was inversely related to that of CD38 (P=0.0005), but was not associated with CD49d expression (P=0.96). A significantly lower expression of LAIR1 was observed in patients with Binet stage B or C disease (P=0.023), and in the presence of high-risk cytogenetic abnormalities (P=0.048) or unmutated immunoglobulin heavy chain variable region genes (P<0.0001). At univariate analysis LAIR1(+) was significantly associated with longer time to first treatment (P=0.0002). This favorable effect of LAIR1(+) was confirmed by multivariate analysis (hazard ratio=2.1, P=0.03 for LAIR1). Our results indicate that LAIR1 expression is a reliable and inexpensive marker capable of independently predicting time to first treatment in newly diagnosed unselected patients with chronic lymphocytic leukemia.

B-cell receptor configuration and mutational analysis of patients with chronic lymphocytic leukaemia and trisomy 12 reveal recurrent molecular abnormalities.

Trisomy 12 (+12) is the third most frequent cytogenetic aberration in chronic lymphocytic leukaemia (CLL) retrievable both as the sole chromosomal abnormality or in association with additional alterations. NOTCH1 mutations are known to be more prevalent among +12 patients, whereas mutations of FBXW7, a gene involved in NOTCH1 degradation, that lead to the constitutional activation of NOTCH1 have not been investigated in this setting. We analyzed a unicentric cohort of 44 +12 patients with CLL for mutations of TP53, NOTCH1 and FBXW7 genes, and we correlated them with B-cell receptor (BCR) configurations. FBXW7, TP53 and NOTCH1 mutations were identified in 4.5%, 6.8% and 18.2% of patients, respectively. FBXW7 and NOTCH1 mutations appeared in a mutually exclusive fashion, suggesting that both aberrations might affect the same biological pathway. We found that 44.1% of +12 CLL patients had stereotyped B-cell receptors, which is significantly higher than that observed in patients with CLL and no +12 (27%, p = 0.01). Subsets #1, #8, #10, #28 and #59 were the most represented stereotyped patterns, and IGHV4-39*01 was the gene configuration most commonly used. There was a significantly higher risk for Richter's syndrome (RS) transformation in patients with NOTCH1 or FBXW7 mutations, with four of the seven (57%) patients developing RS and characterized at least by one of the two abnormalities. These observations suggest that, similarly to the aberrations of NOTCH1, FBXW7 gene mutations may also result in cell proliferation and evasion from apoptosis in patients with +12 CLL. Together with the extremely high frequency of stereotyped BCRs and RS transformation, these abnormalities appear to cluster in these CLL patients with additional chromosome 12, suggesting a connection with the prognosis of the disease.

Kaposi's Sarcoma: Evaluation of Clinical Features, Treatment Outcomes, and Prognosis in a Single-Center Retrospective Case Series.

Kaposi's sarcoma (KS) is a rare angioproliferative tumor classified in four different clinical-epidemiological forms. The diagnosis is based on histopathological and immunohistochemical analyses. The treatment is heterogeneous and includes several local and systemic therapeutic strategies. Methods: This is a retrospective cohort study including 86 KS patients treated between 1993 and 2022 at the University Hospital of Padua (AOPD) and at the Veneto Institute of Oncology (IOV). The data were extracted from an electronic database. Survival curves were generated using the Kaplan-Meier method, and Cox regression models were employed to explore associations with overall and disease-free survival. The male sex (89.53%), classical variant (43.02%), and cutaneous involvement (77.9%) were predominant. More than 61.6% of patients received a single treatment. Surgery, antiretroviral therapy, and chemotherapy were the mostly adopted approaches. A persistent response was observed in approximately 65% of patients, with a 22% relapse rate (at least 2 years). The overall survival ranges from 90 to 70% at 2 to 10 years after the diagnosis. Iatrogenic KS demonstrated a higher mortality (52.9%). This study reflects our experience in the management of KS. Comorbidities are very frequent, and treatments are heterogeneous. A multidisciplinary approach involving multiple referral specialists is essential for the appropriate management of this disease during diagnosis, treatment, and follow-up.

The combination of rituximab, bendamustine, and cytarabine for heavily pretreated relapsed/refractory cytogenetically high-risk patients with chronic lymphocytic leukemia.

Treatment of patients with B-cell chronic lymphocytic leukemia (CLL) relapsed/refractory (R/R) to conventional treatments is particularly challenging. The combination of bendamustine and cytarabine has demonstrated distinct and synergistic mechanisms of action in preclinical studies on cell lines and primary tumor cells of several B-cell lymphomas, including 17p deleted or TP53 mutated CLL. The efficacy of rituximab (375 mg/m(2) , Day 1), plus bendamustine (70 mg/m(2) , days 1-2), and cytarabine (800 mg/m(2) , Day 1-3; R-BAC), every 28 days for up to four courses, was evaluated in a pilot trial enrolling 13 patients with very selected high-risk R/R CLL. All patients (median age 60 years, range 53-74) had symptomatic Binet stage B or C active disease requiring treatment, were characterized by adverse cytogenetics (17p deletion, 11q deletion, or both), unmutated immunoglobulin heavy-chain variable region, and were heavily pretreated (1-5, median three previous lines). Overall, R-BAC was well tolerated with limited non-hematological toxicity. Major toxicities were transient Grade 3/4 neutropenia and thrombocytopenia in 84% and 85% of patients, respectively. Overall response rate (OR) was 84%, including complete and partial response in 38% and 46% of patients, respectively. Patients with 17p deletion had an OR of 78%. After a median follow-up of 17 months, median progression-free survival was 16 months while median overall survival (OS) was not reached (1-year OS: 75 ± 13%). R-BAC is an active regimen in R/R heavily pretreated high-risk patients with CLL, representing an option for the treatment of patients that are usually refractory to standard therapy.

Double productive immunoglobulin sequence rearrangements in patients with chronic lymphocytic leukemia.

The immunoglobulin heavy chain variable (IGHV) gene mutational status represents a major prognostic marker in chronic lymphocytic leukemia (CLL). Usually, the prognostic implications of IGHV gene analysis can be reliably ascertained but, occasionally, double productive rearrangements have been detected. Clinical presentation and biological features of such cases are unknown. Sixty patients with morphologically and phenotypically monoclonal CLL but double productive IGHV rearrangements were retrospectively identified by mRNA analysis from three Hematology Institutions. Clinical and biological features and survival of these 60 patients were compared with a control group of patients with CLL and single IGHV rearrangement. A prospective registry was used to assess the epidemiology of double productive IGHV among incidental patients with CLL. Using standard criteria to define IGHV-mutated (M) or unmutated (U) cases, 39 of the 60 patients (65%) with double productive IGHV rearrangement had concordant status (23 MM, 16 UU), while 21 (35%) had discordant IGHV status. As compared with M patients, the MM ones had lower CD38 expression, more favorable cytogenetics and more indolent clinical behavior. Cases with UU had similar characteristics of U patients. Discordant cases presented with adverse prognostic features and had an aggressive clinical behavior requiring early treatment, similar to U patients. The prevalence of double IGHV was 3.1%. Patients with CLL with double concordant mutational status (MM or UU) have a clinical course similar to that of the corresponding single IGHV status, while those exhibiting discordant status represent a high risk population. This may help correct stratification within clinical trials.

Isolated erythrocytosis: study of 67 patients and identification of three novel germ-line mutations in the prolyl hydroxylase domain protein 2 (PHD2) gene.

The oxygen sensing pathway modulates erythropoietin expression. In normal cells, intracellular oxygen tensions are directly sensed by prolyl hydroxylase domain (PHD)-containing proteins. PHD2 isozyme has a key role in tagging hypoxia-inducible factor (HIF)-α subunits for polyubiquitination and proteasomal degradation. Erythrocytosis-associated PHD2 mutations reduce hydroxylation of HIF-α. The investigation of 67 patients with isolated erythrocytosis, either sporadic or familial, allowed the identification of three novel mutations in the catalytic domain of the PHD2 protein. All new mutations are germ-line, heterozygous and missense, and code for a predicted full length mutant PHD2 protein. Identification of the disease-causing genes will be of critical importance for a better classification of familial and acquired erythrocytosis, offering additional insight into the erythropoietin regulating oxygen sensing pathway.

High dose chemotherapy followed by autologous hematopoietic stem cell transplantation for advanced germ cell tumors: State of the art and a single-center experience.

BACKGROUND: Evidence for the choice of second line, standard vs high dose chemotherapy, (SDCT, HDCT) for patients with relapsed germ cell tumors (GCTs) comes mainly from retrospective studies. MATERIAL AND METHODS: relevant literature was reviewed, considering as endpoints both survival and long term quality of life (QoL). Patients with metastatic GCT progressing after first-line treatment at our Institution were retrospectively evaluated. RESULTS: HDCT seems to achieve a higher rate of long-term remissions. QoL data for this group of patients are lacking. Our experience on 29 patients was in line with these results. Two-year OS for the 18 patients treated with one or two HDCT/PBSCT procedures was 47.5 %, while 2-year PFS was 44 %. For the 11 receiving SDCT 2-year OS was 36.4 %, and 2-year PFS was 32.7 %. CONCLUSIONS: HDCT/PBSCT confirmed to be effective in treating patients with relapsed GCT, but prospective studies are needed.

High ETV6 Levels Support Aggressive B Lymphoma Cell Survival and Predict Poor Outcome in Diffuse Large B-Cell Lymphoma Patients.

The identification of prognostic factors for aggressive B-cell lymphomas still represents an unmet clinical need. We used forward phase protein arrays (FFPA) to identify proteins associated with overall survival (OS) from diagnostic formalin-fixed paraffin-embedded material of diffuse large B-cell lymphoma (DLBCL) patients (n = 47). Univariate Cox regression analysis identified numerous proteins, including immune check-point molecules (PDCD1, PDCD2 and PD1L2) and BCL2 to be significantly associated with OS. However, only ETV6 and PIM2 proteins persisted following multivariate Cox analysis. Independent validation studies by immunohistochemistry and analysis of public gene expression profiles of DLBCL confirmed a prognostic role for high ETV6 and ETV6/PIM2 ratios in DLBCL. ETV6 is a recurrently mutated/deleted gene in DLBCL for which its function in this disease entity is currently unknown. We find that ETV6 is upregulated during oncogenic transformation of germinal center B-cells and that it regulates DLBCL survival, as its acute loss results in marked apoptosis. Fluctuations in survivin (BIRC5) expression levels were associated with this phenomenon. Furthermore, an inverse correlation between ETV6 and BIRC5 expression levels was found and correlated with a response to the BIRC5 inhibitor, YM155. In conclusion, we present evidence for an oncogenic function of ETV6 in DLBCL.

Simultaneous Care in Oncology: A 7-Year Experience at ESMO Designated Centre at Veneto Institute of Oncology, Italy.

Benefits of early palliative care referral in oncology are well-validated. At the Veneto Institute of Oncology-IRCCS, a simultaneous-care outpatient clinic (SCOC) has been active since 2014, where patients with advanced cancer are evaluated by an oncologist together with a palliative care team. We prospectively assessed SCOC patients' characteristics and SCOC outcomes through internal procedure indicators. Data were retrieved from the SCOC prospectively maintained database. There were 753 eligible patients. The median age was 68 years; primary tumor sites were gastrointestinal (75.2%), genitourinary (15.0%) and other sites (9.8%). Predominant symptoms were psychological issues (69.4%), appetite loss (67.5%) and pain (65.9%). Dyspnea was reported in 53 patients (7%) in the referral form, while it was detected in 226 patients (34.2%) during SCOC visits (p < 0.0001). Median survival of patients after the SCOC visit was 7.3 months. Survival estimates by the referring oncologist were significantly different from the actual survival. Psychological intervention was deemed necessary and undertaken in 34.6% of patients, and nutritional support was undertaken in 37.9% of patients. Activation of palliative care services was prompted for 77.7% of patients. Out of 357 patients whose place of death is known, 69.2% died at home, in hospice or residential care. With regard to indicators' assessment, the threshold was reached for 9 out of 11 parameters (81.8%) requested by the procedure. This study confirmed the importance of close collaboration between oncologists and palliative care teams in responding properly to cancer patients' needs. The introduction of a procedure with indicators allowed punctual assessment of a team's performance.

Complete remission of primary cutaneous anaplastic large cell lymphoma after a short course of brentuximab vedotin.

Primary cutaneous anaplastic large cell lymphoma (PCALCL) is a rare CD30+ lymphoproliferative disorder characterized by the development of lesions ranging from papules to large tumors. Most cases present as localized disease, however multifocal and generalized involvement of the skin can occur. Several treatments have been proposed for PCALCL; however a highly effective standard approach to multifocal disease has not yet been elucidated. The disease expression of CD30 antigen in at least 75% of the tumor makes it an optimal target for immunotherapy. The current study presents a case of a 62-year-old male referred to the University of Padua Dermatology Clinic complaining about nodular and ulcerated lesions involving the frontal area and scalp that were 8 cm in diameter. Doses of 180 mg brentuximab vedotin (BV), which is an antibody drug conjugate binding CD30 antigen, were administered every 21 days. A 75% decrease in dimensions after the first infusion and a complete remission after the second was observed. Disease response appeared to be dose-related and adverse reactions, in particular peripheral neuropathy, may be an effect of cumulative toxicity, meaning that treatment cycle reduction should be considered. Based on the present results, A high dose, short course of BV is recommended as a cost-effective approach for PCALCL. However, further studies are required to assess the efficacy and other potential advantages of this therapeutic regimen.

Rituximab and Bendamustine (BR) Compared with Rituximab, Bendamustine, and Cytarabine (R-BAC) in Previously Untreated Elderly Patients with Mantle Cell Lymphoma.

BACKGROUND: Rituximab plus bendamustine (BR), and rituximab, bendamustine, and cytarabine (R-BAC) are well-known induction therapies in elderly patients with mantle cell lymphoma (MCL), according to clinical guidelines. However, a direct comparison between the two regimens has never been performed. METHODS: In this multicentre retrospective study, we compared the outcome of patients with newly diagnosed MCL, treated with BR or R-BAC. Primary endpoint was 2-year progression-free survival (PFS). Inclusion bias was assessed using a propensity score stratified by gender, age, MCL morphology, and MIPI score. RESULTS: After adjusting by propensity score, we identified 156 patients (53 BR, 103 R-BAC) with median age of 72 (53-90). Median follow-up was 46 months (range 12-133). R-BAC was administered in a 2-day schedule or with attenuated dose in 51% of patients. Patients treated with R-BAC achieved CR in 91% of cases, as compared with 60% for BR (p < 0.0001). The 2-year PFS was 87 ± 3% and 64 ± 7% for R-BAC and BR, respectively (p = 0.001). In terms of toxicity, R-BAC was associated with significantly more pronounced grade 3-4 thrombocytopenia than BR (50% vs. 17%). CONCLUSIONS: This study indicates that R-BAC, even when administered with judiciously attenuated doses, is associated with significantly prolonged 2-year PFS than BR in elderly patients with previously untreated MCL.

Characteristics and clinical correlates of MPL 515W>L/K mutation in essential thrombocythemia.

Among 994 patients with essential thrombocythemia (ET) who were genotyped for the MPLW515L/K mutation, 30 patients carrying the mutation were identified (3.0%), 8 of whom also displayed the JAK2V671F mutation. MPLW515L/K patients presented lower hemoglobin levels and higher platelet counts than did wild type (wt) MPL; these differences were highly significant compared with MPLwt/JAK2V617F-positive patients. Reduced hemoglobin and increased platelet levels were preferentially associated with the W515L and W515K alleles, respectively. MPL mutation was a significant risk factor for microvessel disturbances, suggesting platelet hyperreactivity associated with constitutively active MPL; arterial thromboses were increased only in comparison to MPLwt/JAK2wt patients. MPLW515L/K patients presented reduced total and erythroid bone marrow cellularity, whereas the numbers of megakaryocytes, megakaryocytic clusters, and small-sized megakaryocytes were all significantly increased. These data indicate that MPLW515L/K mutations do not define a distinct phenotype in ET, although some differences depended on the JAK2V617F mutational status of the counterpart.

Older cancer patients and COVID-19 outbreak: Practical considerations and recommendations.

Since the COVID-19 outbreak started, it has been affecting mainly older individuals. Among the most vulnerable older individuals are those with cancer. Many published guidelines and consensus papers deal with prioritizing cancer care. Given the lack of high-quality evidence for management of cancer in older patients also in normal times, it is even more stringent to provide some resources on how to avoid both undertreatment and overtreatment in this population, who as of now is twice challenged to death, due to both a greater risk of getting infected with COVID-19 as well as from cancer not adequately addressed and treated. We hereby discuss some general recommendations (implement triage procedures; perform geriatric assessment; carefully assess comorbidity; promote early integration of palliative care in oncology; acknowledge the role of caregivers; maintain active take in charge to avoid feeling of abandonment; mandate seasonal flu vaccination) and discuss practical suggestions for specific disease settings (early-stage and advanced-stage disease for solid tumors, and hematological malignancies). The manuscript provides resources on how to avoid both undertreatment and overtreatment in older patients with cancer, who as of now is twice challenged to death, due to both a greater risk of getting infected with COVID-19 as well as from cancer not adequately addressed and treated.

Aggressive Merkel Cell Carcinoma After Janus Kinase Inhibitor Ruxolitinib for Polycythemia Vera.

Merkel cell carcinoma (MCC) is a rare neuroendocrine carcinoma of the skin. It is highly aggressive and represents the second most common cause of skin cancer-related death. Ruxolitinib is an orally administered selective inhibitor of Janus associated kinases1 and 2, which is used in the management of patients with symptomatic myelofibrosis and polycythemia vera who are non-responders or intolerant to hydroxyurea. Herein, we report the case of a 47-year-old woman with a 14-year history of chronic myeloproliferative syndrome initially treated with hydroxyurea for 4 years. She was then enrolled in the Response trial and treated for 7 years with ruxolitinib subsequently developing an MCC. This report shows the possibility of development of MCC in patients treated with ruxolitinib. Periodic skin examination is indicated in patients who undergo ruxolitinib therapy, especially if they have a history of skin cancer; dermatologists and oncohematologists should be aware of this possibility in order to introduce appropriate preventive strategies.

Rituximab, bendamustine, and low-dose cytarabine as induction therapy in elderly patients with mantle cell lymphoma: a multicentre, phase 2 trial from Fondazione Italiana Linfomi.

BACKGROUND: The combination of rituximab, bendamustine, and cytarabine (R-BAC) was highly active in a pilot trial of mantle cell lymphoma, but its use was restricted by high haematological toxicity. We aimed to assess the efficacy and safety of an R-BAC regimen with low-dose cytarabine (RBAC500). METHODS: In this multicentre, phase 2 trial, we recruited previously untreated patients with an established histological diagnosis of mantle cell lymphoma from 29 Fondazione Italiana Linfomi centres in Italy. Patients had to be older than 65 years and fit according to the comprehensive geriatric assessment, or aged 60-65 years if they were ineligible for high-dose chemotherapy plus autologous stem-cell transplantation and were fit or unfit. All patients received RBAC500 (rituximab 375 mg/m2 on day 1, bendamustine 70 mg/m2 on days 2 and 3, and cytarabine 500 mg/m2 on days 2-4; all administered intravenously) every 4 weeks for up to six cycles. Primary endpoints were the proportion of patients achieving complete response at the end of treatment and toxicity, defined as the occurrence of any of the stop treatment criteria or of any episode of relevant toxicity. All patients who started at least one cycle of RBAC500 were included in the primary and safety analyses. Using efficacy and toxicity as a composite primary endpoint, we considered the final conclusion positive if more than 28 of 57 patients achieve complete response and fewer than 18 of 57 patients report toxicities. This study is registered with EudraCT, number 2011-005739-23, and ClinicalTrials.gov, number NCT01662050, and is completed. FINDINGS: Between May 2, 2012, and Feb 25, 2014, we enrolled 57 patients (median age 71 years, IQR 67-75). 54 (95%) patients received at least four RBAC500 cycles (three discontinued because of toxicity), and 38 (67%) completed six cycles. Two (4%) had disease progression (one after the fourth cycle and one after the sixth cycle). All 52 (91%, lower limit of one-sided 95% CI 85%) remaining patients achieved complete response at the end of treatment. 23 (40%, upper limit of one-sided 95% CI 53%) of 57 patients had at least one episode of relevant toxicity. The most frequent grade 3-4 haematological toxicities were neutropenia (149 [49%] of 304 cycles) and thrombocytopenia (158 [52%]). Most treatment-related non-haematological adverse events were of grade 1-2, with the most frequent ones being fatigue (14 [25%] patients), nausea or vomiting (12 [21%]), and infusion-related reactions or tumour lysis syndrome (12 [21%]). 41 (72%) patients required a dose reduction. 12 patients died during the study, but no deaths were related to treatment. INTERPRETATION: RBAC500 is an effective treatment for elderly patients with mantle cell lymphoma and, despite not meeting our prespecified safety boundary, haematological toxicity was manageable with appropriate supportive care and dose reduction. Since maintenance therapy is not required, RBAC500 could be considered an option and should be studied in phase 3 trials. FUNDING: Fondazione Italiana Linfomi and Mundipharma.