Molecular Features of HHV8 Monoclonal Microlymphoma Associated with Kaposi Sarcoma and Multicentric Castleman Disease in an HIV-Negative Patient.

Human herpesvirus 8 (HHV8)-associated diseases include Kaposi sarcoma (KS), multicentric Castleman disease (MCD), germinotropic lymphoproliferative disorder (GLPD), Kaposi sarcoma inflammatory cytokine syndrome (KICS), HHV8-positive diffuse large B-cell lymphoma (HHV8+ DLBCL), primary effusion lymphoma (PEL), and extra-cavitary PEL (ECPEL). We report the case of a human immunodeficiency virus (HIV)-negative male treated for cutaneous KS, who developed generalized lymphadenopathy, hepatosplenomegaly, pleural and abdominal effusions, renal insufficiency, and pancytopenia. The excised lymph node showed features of concomitant involvement by micro-KS and MCD, with aggregates of HHV8+, Epstein Barr virus (EBV)-negative, IgM+, and lambda+ plasmablasts reminiscent of microlymphoma. Molecular investigations revealed a somatically hypermutated (SHM) monoclonal rearrangement of the immunoglobulin heavy chain (IGH), accounting for 4% of the B-cell population of the lymph node. Mutational analyses identified a pathogenic variant of KMT2D and variants of unknown significance in KMT2D, FOXO1, ARID1A, and KMT2A. The patient died shortly after surgery. The histological features (HHV8+, EBV-, IgM+, Lambda+, MCD+), integrated with the molecular findings (monoclonal IGH, SHM+, KMT2D mutated), supported the diagnosis of a monoclonal HHV8+ microlymphoma, with features intermediate between an incipient HHV8+ DLBCL and an EBV-negative ECPEL highlighting the challenges in the accurate classification of HHV8-driven lymphoid proliferations.

The application of a multidisciplinary approach in the diagnosis of Castleman disease and Castleman-like lymphadenopathies: A 20-year retrospective analysis of clinical and pathological features.

BACKGROUND: Castleman disease (CD) comprises a group of rare and heterogeneous haematological disorders, including unicentric (UCD) and multicentric (MCD) forms, the latter further subdivided into HHV8-MCD, POEMS-MCD and idiopathic-MCD (iMCD). However, according to the Castleman Disease Collaborative Network guidelines, the diagnosis of CD can only be achieved through collaboration between clinicians and pathologists. METHODS: We applied these clinical and pathological criteria and implement with clonality testing to a retrospective cohort of 48 adult and paediatric Italian patients diagnosed with reactive lymphadenitis with CD-like histological features. RESULTS: We confirmed the diagnosis of CD in 60% (29/48) of the cases, including 12 (41%) UCD and 17 (59%; five HHV8-MCD, three POEMS-MCD and nine iMCD) MCD. Of the remaining 19 cases (40%) with multiple lymphadenopathy, 5 (26%) were classified as autoimmune diseases, 1 (5%) as autoimmune lymphoproliferative disorder, 1 (5%) as IgG4-related disease, 11 (83%) as reactive lymphadenitis and 1 (5%) as nodal marginal zone lymphoma. CONCLUSIONS: Our study emphasizes the importance of the multidisciplinary approach to reactive lymphadenitis with CD-like features in order to achieve a definitive diagnosis and choose the appropriate treatment.

Correction: Bocci et al. Remarkable Remission Rate and Long-Term Efficacy of Upfront Metronomic Chemotherapy in Elderly and Frail Patients, with Diffuse Large B-Cell Lymphoma. J. Clin. Med. 2022, 11, 7162.

In the original publication [...].

A Fondazione Italiana Linfomi cohort study of R-COMP vs R-CHOP in older patients with diffuse large B-cell lymphoma.

Rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) is the most commonly used regimen for the upfront treatment of diffuse large B-cell lymphoma (DLBCL). However, it is associated with cardiotoxicity, especially in older patients. Substituting doxorubicin with non-PEGylated liposomal doxorubicin (R-COMP) may reduce the risk of cardiac events, but its efficacy has never been demonstrated in prospective trials. We describe the characteristics and outcome of patients with DLBCL aged ≥65 years prospectively enrolled in the Elderly Project by the Fondazione Italiana Linfomi and treated with full doses of R-CHOP or R-COMP per local practice. Starting from 1163 patients, 383 (55%) were treated with R-CHOP and 308 (45%) with R-COMP. Patients treated with R-COMP were older (median age, 76 vs 71 years), less frequently fit at simplified geriatric assessment (61% vs 88%; P < .001), and had a more frequent baseline cardiac disorders (grade >1, 32% vs 8%; P < .001). Three-year progression-free survival (PFS) was similar between R-CHOP and R-COMP (70% and 64%); 3-year overall survival was 77%, and 71% respectively. R-CHOP was associated with better PFS vs R-COMP only in the Elderly Prognostic Index (EPI) low-risk group. The two groups had similar rates of treatment interruptions due to toxicities or of cardiac events (P = 1.00). We suggest R-COMP is a potentially curative treatment for older patients with intermediate- or high-risk EPI, even in the presence of a baseline cardiopathy. R-CHOP is confirmed as the standard therapy for low risk patients.

Efficacy of Residual Site Radiation Therapy (ISRT) in Patients with Primary Mediastinal Lymphoma with Deauville Score 4 Following R-CHT: Results of a Retrospective Mono Institutional Study.

BACKGROUND: In order to evaluate the efficacy of residual site radiation therapy (RSRT) in terms of progression-free survival (PFS) and overall survival (OS) in patients with primary mediastinal lymphoma (PMBCL) with Deauville Score 4 (DS 4) following rituximab and chemotherapy treatment (R-ICHT). METHODS: Thirty-one patients with PMBCL were recruited. After completion of R-ICHT, patients were staged with 18F-fluorodeoxyglucose positron-emission tomography, showing DS 4, and were treated with adjuvant RSRT. The chosen techniques for RT delivery were intensity-modulated radiation therapy (IMRT) or three-dimensional conformal RT (3D-CRT). Most patients underwent the first one using cone-beam computed tomography (CBCT). All patients were evaluated every 3 months for the first 2 years and every 6 months afterwards for a period of at least 5 years, with clinical and radiological procedures as required. RESULTS: All patients received RSRT with a dose of 30 Gy in 15 fractions. The median follow-up time of 52.7 months (IQR: 26-64.1 months). The 5-year OS rate was 100%. The 2-year and 5-year PFS rates were 96.7% and 92.5%, respectively. Patients with relapsed disease had been treated with high-dose chemotherapy (HDC) and autologous stem cell transplantation (auto-SCT). CONCLUSION: RSRT in patients with PMBCL treated with ICHT and DS 4 did not impact unfavorably on patient survival.

Effects of ABVD chemotherapy on ovarian function: epidemiology, hormonal dosages and ultrasound morphologic analyses in 270 patients with Hodgkin's disease.

Introduction: Classical Hodgkin Lymphoma (HL) is a lymphoproliferative disease typically diagnosed in the young. The excellent results obtained with current treatment lead to long survival with age-related complications affecting patients' survival and quality of life. One issue affecting HL patients is infertility. This problem can be easily overcome in males with seminal liquid cryopreservation, however, in females it is more complex either in terms of the quality of the cryopreserved material or the patients' age at diagnosis. Moreover, not all chemo- or radio-therapies have the same negative impact on fertility.The main objectives of this study was to collect epidemiological information on HL patients involved in fertility preservation counseling and to analyze the impact of ABVD (adriamycin, bleomycin, vinblastine, and dacarbazine), the standard treatment for HL, on ovarian function, hormonal levels and ovarian and uterine tissue morphologies. Patterns of fertility preservation were also reported. Methods: Data were obtained from 270 female patients at HL onset who were interested in fertility counseling prior to therapy initiation. Each patient was assessed at HL diagnosis for levels of Anti-Mullerian Hormone (AMH), Follicle Stimulating Hormone (FSH), and 17ß-oestradiol (17ß-oe), with additional assessments at 6 and 12 months after chemotherapy. Patients were evaluated with ultrasound scans to study the number of ovarian follicles and the degree of uterine thickness at the same timepoints. Results: The average patient AMH level showed a statistically significant reduction at 6 months after chemotherapy (p=0.05) and by the 12 month time point returned to near pre-chemotherapy values. FSH and 17ß-oe levels did not significantly vary throughout the study period. ABVD chemotherapy was associated with a significant reduction of both ovarian follicles and endometrial thickness at the 6 month time point followed by a recovery at the 12 time point in both ovaries. Different results were observed when patients changed treatment to a more intensive one. Discussion: Based on the results from the hormonal measurements and the follicle echography, it appears that the toxic effect of ABVD on fertility is transient, whereas, in contrast, more intensive therapies may potentially be more harmful and long-lasting.

Correspondence in reference to the previously published manuscript: Reduction of cycles of bendamustine plus rituximab therapy in the cases with good response for indolent B-cell lymphomas.

Takezaki et al. analyzed the outcome of 57 patients with indolent lymphomas treated with Bendamustine plus Rituximab (BR) according to the number of cycles received, showing that patients who discontinued BR after four cycles had similar outcomes compared to patients who received five or six cycles. Considering the similarities but also the differences between indolent lymphomas and chronic lymphocytic leukemia (CLL), we enriched the results obtained with a cohort of CLL patients treated with BR starting from the experience of the Lazio region group on CLL. Out of 115 patients, 97 (84%) received 4-6 cycles of BR, while 18 (16%) received 1-3 cycles. The outcome of the group of patients who received at least 4 cycles was superior in terms of response rate (ORR 96% vs. ORR 83%, p = 0.041; CR 58% vs. CR 28%, p = 0.052 respectively) and PFS [median PFS 52.6 (40.3-64.9) versus 26.2 (19.3-33.0) months, p < 0.001]. The number of patients undergoing 4 cycles of BR (4-cycles group) and 5-6 cycles (over-4-cycles group) was 9 and 88, respectively. Compared to analysis conducted by the Japanese group in indolent lymphomas, in CLL we did not observe any difference between the outcome of the 4-cycles group and the over-4-cycles group in terms of ORR (89% vs. 97%, p = 0.268) and in survival [median PFS 40.8 (13.7-67.8) versus 52.6 (38.7-66.5) months, p = 0.117]. Moreover, we observed that patients who achieved a clinical CR showed overlapping outcomes with patients who received more than 4 cycles [CR vs. non-CR median PFS not reached vs. 11.0 months; over-4-cycles group median PFS 52.6 months (40.3-64.9); p < 0.001]. Nowadays chemoimmunotherapy with BR is reserved to fit elderly CLL patients, and there are many chemo-free treatment options available; therefore, discontinuation after 4 cycles may be permissible in patients who obtained a CR in order to limit toxicity as much as possible.

[18F]FDG PET/CT in Patients Affected by SARS-CoV-2 and Lymphoproliferative Disorders and Treated with Tocilizumab.

OBJECTIVES: Interstitial pneumonia is a severe complication induced by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Several treatments have been proposed alone or, more often, in combination, depending, also, on the presence of other organ disfunction. The most frequently related, well-described, and associated phenomenon is pan-lymphopenia with circulating, high levels of cytokines. We report, here, on two patients with COVID-19 and lymphoproliferative disorders treated with Tocilizumab (a humanized monoclonal antibody against the interleukin-6 receptor) and followed by an [18F]FDG PET/CT to early evaluate the therapy's efficacy. METHODS: One patient with angioimmunoblastic T-lymphoma (A), one with Hodgkin lymphoma (A), and both with positive RT-PCR for SARS-CoV-2 and with similar clinical findings of interstitial pneumonia at the CT scan, were imaged by [18F]FDG PET/CT before and 14 days after a single dose of Tocilizumab. RESULTS: In both patients, the basal [18F]FDG PET/CT showed a diffused lung parenchyma uptake, corresponding to the hyperdense areas at the CT scan. After 2 weeks of a Tocilizumab infusion, patient B had an improvement of symptoms, with normalization of the [18F]FDG uptake. By contrast, patient A, who was still symptomatic, showed a persisting and abnormal distribution of [18F]FDG. Interestingly, both patients showed a low bone marrow uptake of [18F]FDG at the diagnosis and after 15 days, while the spleen uptake was low only in lymphopenic patient A; both are indirect signs of an immune deficiency. CONCLUSIONS: In conclusion, in these two patients, interstitial pneumonia was efficiently treated with Tocilizumab, as demonstrated by the [18F]FDG PET/CT. Our results confirm that interleukin-6 (IL6) has a role in the COVID-19 disease and that anti-cytokine treatment can also be performed in patients with lymphoproliferative disorders.

Remarkable Remission Rate and Long-Term Efficacy of Upfront Metronomic Chemotherapy in Elderly and Frail Patients, with Diffuse Large B-Cell Lymphoma.

The upfront treatment of very elderly and frail patients with diffuse large B-cell lymphoma (DLBCL) is still a matter of debate. Herein, we report results of the metronomic all-oral DEVEC [prednisolone/deltacortene®, vinorelbine (VNR), etoposide (ETO), cyclophosphamide] combined with i.v. rituximab (R). This schedule was administered as a first line therapy in 22 elderly/frail DLBCL subjects (median age = 84.5 years). In 17/22 (77%) patients, the Elderly-IPI-score was high. After a median follow-up of 24 months, 15 patients had died: seven (50%) for causes unrelated to DLBCL or its treatment, six (40%) for progression, and two (13%) for multiorgan failure. Six treatment-pertinent serious-adverse-events occurred. At the end of induction, 14/22 (64%) achieved complete remission; overall survival and event-free survival at 24 months were both 54% (95% CI = 32−72%), while the time to progression was 74% (95% CI = 48−88%). Furthermore, antiproliferative and proapoptotic assays were performed on DLBCL/OCI-LY3 cell-line using metronomic VNR and ETO and their combination. Both metronomic VNR and ETO had concentration-dependent antiproliferative (IC50 = 0.036 ± 0.01 nM and 7.9 ± 3.6 nM, respectively), and proapoptotic activities in DLBCL cells. Co-administration of the two drugs showed a strong synergism (combination index < 1 and dose reduction index > 1) against cell proliferation and survival. This low-dose schedule seems to compare favourably with intravenous-CHEMO protocols used in the same subset. Indeed, the high synergism shown by metronomic VRN+ETO in in vitro studies, explains the remarkable clinical responses and it allows significant dose reductions.

Angioimmunoblastic T-Cell Lymphoma with Exuberant CD30-Positive Follicular Dendritic Cell Proliferation in a SARS-CoV-2 Patient: The Role of Mutational Analysis to Exclude an Associated Follicular Dendritic Cell Sarcoma.

Follicular dendritic cell (FDC) proliferation in angioimmunoblastic T-cell lymphoma (AITL) is still not well defined, challenging the accurate differential diagnosis between the AITL with expanded follicular dendritic cell meshwork and the combined AITL and follicular dendritic cell sarcoma (FDCS). Herein, we reported the case of a 58-year-old male with coexisting SARS-CoV-2 infection and AITL with an exuberant CD30-positive FDC proliferation, in which genetic analysis identified mutations of genes commonly involved in AITL but not in FDC sarcoma (i.e., RHOA, TET2, DNMT3A, and IDH2), thus supporting the reactive nature of the CD30-positive FDC expansion.

Physicians' Perceptions of Clinical Utility of a Digital Health Tool for Electronic Patient-Reported Outcome Monitoring in Real-Life Hematology Practice. Evidence From the GIMEMA-ALLIANCE Platform.

Digital health tools are increasingly being used in cancer care and may include electronic patient-reported outcome (ePRO) monitoring systems. We examined physicians' perceptions of usability and clinical utility of a digital health tool (GIMEMA-ALLIANCE platform) for ePRO monitoring in the real-life practice of patients with hematologic malignancies. This tool allows for the collection and assessment of ePROs with real-time graphical presentation of results to medical staff. Based on a predefined algorithm, automated alerts are sent to medical staff. Participating hematologists completed an online survey on their experience with the platform. Of the 201 patients invited to participate between December 2020 and June 2021 (cut-off date for current analysis), 180 (90%) agreed to enter the platform and had a median age of 57 years. Twenty-three hematologists with a median age of 42 years and an average of 17 years of experience in clinical practice were surveyed. All hematologists agreed or strongly agreed that the platform was easy to use, and 87%, agreed or strongly agreed that ePROs data were useful to enhance communication with their patients. The majority of physicians (78%) accessed the platform at least once per month to consult the symptom and health status profile of their patients. The frequency of access was independent of physician sex (p=0.393) and years of experience in clinical practice (p=0.404). In conclusion, our preliminary results support the clinical utility, from the perspective of the treating hematologist, of integrating ePROs into the routine cancer care of patients with hematologic malignancies.

All-oral metronomic DEVEC schedule in elderly patients with peripheral T cell lymphoma.

PURPOSE: Peripheral T cell lymphomas (PTCLs) have an overall poor prognosis. Indeed, registry data in elderly patients show that the median progression-free survival (mPFS) following first- and second-line therapies are only 6.7 and 3.1 months, respectively. The aim of the study is to show the activity of metronomic chemotherapy, a regular administration of low chemotherapeutic drug doses allowing a favourable toxicity profile, on elderly PTCL patients. METHODS: We report a series of 17 PTCL patients, treated with the all-oral metronomic schedule DEVEC (prednisolone-etoposide-vinorelbine-cyclophosphamide) in four Italian centres. Patients 5/17 (29.4%) were treatment-naïve (naïve) and 12/17 (70.6%) were relapsed-refractory (RR), respectively. The median age was 83 years (range 71-87) and 71.5 years (range 56-85) for naïve and RR, respectively. In vitro activity of metronomic vinorelbine (VNR), etoposide (ETO) and their concomitant combination on HH, a PTCL cell line, was also assessed. RESULTS: Histology: PTCL-not-otherwise-specified = 12; angioimmunoblastic = 2; NK/T nasal type = 1; adult-type leukaemia lymphoma = 1, transformed Mycosis Fungoides = 1. The overall response rate was 80 and 58% in naïve and RR, respectively; whereas the PFS was 20 in naïve (95% CI 0-43) and 11 months (95% CI 4.2-17.8) in RR. The occurrence of relevant adverse events was 23.5%, which was managed with ETO dose reduction. In vitro experiments showed that both metronomic VNR and ETO caused a significant inhibitory activity on HH cells and a strong synergism when administered concomitantly. CONCLUSION: All-oral DEVEC showed an encouraging activity and acceptable toxicity. This schedule deserves further studies in elderly PTCL also for assessing combinations with targeted drugs.

Residual Site Radiotherapy After Immunochemotherapy in Primary Mediastinal B-Cell Lymphoma: A Monoinstitutional Retrospective Study.

AIM: To evaluate the efficacy of residual site radiation therapy (RSRT) on local control (LC), progression-free (PFS) and overall (OS) survival in patients with primary mediastinal lymphoma (PMBCL), following rituximab and chemotherapy treatment (ICHT). PATIENTS AND METHODS: The study included 34 patients with PMBCL treated between 2006 and 2014 with ICHT with/without autologous stem cell transplantation and RSRT. Between the end of ICHT/stem cell transplantation and RSRT, patients were evaluated with 18F-fluorodeoxyglucose positron-emission tomography. The gross tumor volume included morphological mediastinal residual disease after ICHT/SCT. The percentage of LC, PFS and OS were assessed. RESULTS: All patients received RSRT with a median dose of 30 Gy. Median follow-up was 82 months. One patient out of 34 (3%) showed progressive disease 9 months from diagnosis. The 10-year PFS and OS were 97% and 97% respectively. CONCLUSION: RSRT in patients with PMBCL treated with ICHT did not impact unfavorably on LC and patient survival.

The neutrophil/lymphocyte ratio ≥3.5 is a prognostic marker in diffuse large B-cell lymphoma: a retrospective analysis from the database of the Italian regional network 'Rete Ematologica del Lazio per i Linfomi' (RELLI).

In solid tumors and lymphomas, the neutrophil/lymphocyte (N/L) ratio at diagnosis has been shown to be a prognostic factor. The aim of our study was to validate the originally reported N/L ratio cut-point of 3.5 in patients with diffuse large B-cell lymphoma (DLBCL) registered in an Italian real-life database. The prognostic role of the N/L ratio at diagnosis on event-free survival (EFS) and overall survival (OS) was assessed in 505 patients with DLBCL. Patients with an N/L ratio <3.5 (n = 249) had a 4-year EFS probability of 76% and OS probability of 86%, significantly higher than the 4 year EFS rate of 48% and OS rate of 64% in patients with N/L ratio ≥3.5 (n = 256, both p<.0001). The N/L ratio was an independent prognostic factor in the multivariate analysis including the IPI score, and could separate patients with a low/intermediate risk IPI (IPI <3).

The metronomic all-oral DEVEC is an effective schedule in elderly patients with diffuse large b-cell lymphoma.

Metronomic-chemotherapy (M-CHT) has been rarely assessed in non-Hodgkin-lymphoma (NHL). Therefore, in 2011 we started experimenting a new all-oral M-CHT schedule termed DEVEC (Deltacortene®, etoposide, vinorelbine, cyclophosphamide, +/-Rituximab) in diffuse-large-B-cell lymphoma (DLBCL) patients. Methods Patients with stage Ib-IV were enrolled as follows: 1) treatment-naïve, frail ≥65y, or unfit ≥85y; and 2) relapsed/refractory (R/R) ≥55y. Data were prospectively collected from six Italian centres and compared for efficacy to two reference groups, treated with established iv Rituximab-CHT in 1st and 2nd line respectively. Results from April-2011 to March-2018, 17/51(33%) naïve, 21/51(41%) refractory and 13/51(25.5%) relapsed patients started DEVEC; 39/51(76.5%) were de-novo DLBCL; 10/51(19.6%) transformed-DLBCL and 2/51(3.9%) unclassifiable-DLBCL/classical-Hodgkin-lymphoma. The median age was 85y (range=77-93) and 78y (range=57-91) in naïve and R/R respectively and overall the DEVEC patients had very poor features compared to the reference. The rate of grade≥3 haematological-AEs was 43%(95CI=29-58%): G3-neutropenia was the most frequent; grade≥3 extra-haematological-AEs was 13.7% (95%CI=5.4-25.9%), the most frequent was infection. One-year OS and PFS were 67% and 61% for naive, 60% and 50% for reference-naïve respectively; Cox proportional hazard ratio (Cox-PH-ratio) for OS and PFS were 0.69 (95%CI=0.27-1.76;p=.441) and 0.68 (95%CI=0.28-1.62;p=.381) respectively. One-year OS and PFS were 48% and 39% in the R/R, 36% and 17% in the reference-R/R respectively; Cox-PH-ratio for OS and PFS, were 0.76 (95%CI=0.42-1.40; p=.386) and 0.48 (95%CI=0.28-0.82; p=.007) respectively. Conclusion The favourable activity of DEVEC compared to a real-life series and the convenience of an oral administration, may possibly lay the groundwork for a paradigm-shift in the treatment of elderly DLBCL.

A rare BCR-ABL1 transcript in Philadelphia-positive acute myeloid leukemia: case report and literature review.

BACKGROUND: Philadelphia (Ph) chromosome results from the reciprocal translocation t(9;22)(q34.1;q11.2) and is diagnostic for chronic myeloid leukemia (CML). However, this translocation is also found in acute lymphoid leukemia (ALL), as well as in rare cases of acute myeloid leukemias (AML). Most patients with CML harbor either the e13a2 or the e14a2 BCR-ABL fusion product, while a small subset of the cases expresses e1a2 or e19a2 transcripts. Moreover, several atypical BCR-ABL1 transcripts, beside the most common e1a2, e13a2 and e14a2, have been described, mainly in patients with CML. However, ALL and de novo AML may also carry BCR-ABL1 atypical transcripts which will confer a poor prognosis. CASE PRESENTATION: A 78-years old male was admitted at our hospital with clinical and laboratory features allowing to make the diagnosis of AML. No evidence of a preceding CML (splenomegaly or basophilia) was found. The karyotype on G-banded metaphases was 46,XY, t(9;22)(q34;q11). While the molecular analysis was ongoing, the patient started treatment based on hydroxyurea followed by 5-aza-2'-deoxycytidine. The molecular biology analysis revealed the simultaneous presence of the common p190 e1a2 and the rare e6a2 isoforms. Because of persistent pancytopenia and presence of blasts, according to the molecular data, he was then switched to tyrosine kinase inhibitors (TKIs) treatment. Nevertheless, after 2 months, the patient was still refractory to second line treatment dying because of a pulmonary infection. CONCLUSION: The atypical p190 e6a2 transcript seems to be associated in AML with aggressive disease. TKI therapy alone does not seem to control the disease. Prompt observations on these patients carrying rare BCR-ABL1 transcripts may help to establish optimal treatment approaches on these aggressive BCR-ABL1 phenotypes in different setting of patients.

Tumor-associated and immunochemotherapy-dependent long-term alterations of the peripheral blood NK cell compartment in DLBCL patients.

Natural Killer (NK) cells are a key component of tumor immunosurveillance and thus play an important role in rituximab-dependent killing of lymphoma cells via an antibody-dependent cellular cytotoxicity (ADCC) mechanism. We evaluated the phenotypic and functional assets of peripheral blood NK cell subsets in 32 newly-diagnosed diffuse large B-cell lymphoma (DLBCL) patients and in 27 healthy controls. We further monitored long-term modifications of patient NK cells for up to 12 months after rituximab-based immunochemotherapy. At diagnosis, patients showed a higher percentage of CD56dim and CD16+ NK cells, and a higher frequency of GrzB+ cells in CD56dim, CD56bright, and CD16+ NK cell subsets than healthy controls. Conversely, DLBCL NK cell killing and interferon γ (IFNγ) production capability were comparable to those derived from healthy subjects. Notably, NK cells from refractory/relapsed patients exhibited a lower "natural" cytotoxicity. A marked and prolonged therapy-induced reduction of both "natural" and CD16-dependent NK cytotoxic activities was accompanied by the down-modulation of CD16 and NKG2D activating receptors, particularly in the CD56dim subset. However, reduced NK cell killing was not associated with defective lytic granule content or IFNγ production capability. This study firstly describes tumor-associated and therapy-induced alterations of the systemic NK cell compartment in DLBCL patients. As these alterations may negatively impact rituximab-based therapy efficacy, our work may provide useful information for improving immunochemotherapeutic strategies.