Use of a real-world synthetic control arm for direct comparison of lisocabtagene maraleucel and conventional therapy in relapsed/refractory large B-cell lymphoma.

This study used a real-world population as a synthetic comparator for the single-arm TRANSCEND NHL 001 study (TRANSCEND; NCT02631044) to evaluate the efficacy of lisocabtagene maraleucel (liso-cel) compared with conventional (noncellular) therapies in patients with relapsed/refractory (R/R) large B-cell lymphoma (LBCL). Inclusion and exclusion criteria for the real-world study closely matched the enrollment criteria in TRANSCEND. The analytic comparator cohort was created by matching and balancing observed baseline characteristics of real-world patients with those in TRANSCEND using propensity score methodology. Efficacy outcomes comparing liso-cel- (n = 257) and conventional therapy-treated (n = 257) patients, respectively, significantly favored liso-cel: overall response rate (74% vs 39%; p < 0.0001), complete response rate (50% vs 24%; p < 0.0001), median overall survival (23.5 vs 6.8 months; p < 0.0001), and median progression-free survival (3.5 vs 2.2 months; p < 0.0001). These results demonstrated a statistically significant and clinically meaningful benefit of liso-cel in patients with third- or later-line R/R LBCL relative to conventional therapies.Clinical trial registration: ClinicalTrials.gov identifier: NCT02631044.

Immunogenicity of COVID-19 Vaccinations in Hematological Patients: 6-Month Follow-Up and Evaluation of a 3rd Vaccination.

Here we analyzed SARS-CoV-2-specific antibodies and T-cell responses after two coronavirus disease 2019 vaccinations over a six-month period in patients with hematological malignancies and assessed the effect of a third vaccination in a subgroup. Sixty-six patients and 66 healthy controls were included. After two vaccinations seroconversion was seen in 52% and a T-cell-specific response in 59% of patients compared with 100% in controls (p = 0.001). Risk factors for a poor serological response were age (<65a), history of anti-CD20 therapy within the year preceding vaccination, CD19+ B-cells < 110/µL, and CD4+ T-cells > 310/µL. The magnitude of T-cell response was higher in patients <65a and with CD19+ B-cells < 110/µL. Patients and healthy controls demonstrated a significant decrease in SARS-CoV-2 S antibody levels over the period of six months (p < 0.001). A third vaccination demonstrated a strong serological response in patients who had responded to the previous doses (p < 0.001). The third vaccination yielded seroconversion in three out of 19 patients in those without serological response. We conclude that both humoral and cellular responses after SARS-CoV-2 immunization are impaired in patients with hematological malignancies. A third vaccination enhanced B-cell response in patients who previously responded to the second vaccination but may be of limited benefit in patients without prior seroconversion.

SARS-CoV-2-related mortality and treatment delays for cancer patients in Austria : Findings of a multicentric nationwide study.

BACKGROUND: Cancer patients infected with severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) have an increased risk of mortality. Here, we investigated predictive factors for coronavirus disease 2019 (COVID-19) associated mortality in patients with neoplastic diseases treated throughout Austria. METHODS: In this multicentric nationwide cohort study, data on patients with active or previous malignant diseases and SARS-CoV­2 infections diagnosed between 13 March 2020 and 06 April 2021 were collected. Collected data included the stage of the malignant disease and outcome parameters 30 days after the diagnosis of SARS-CoV­2 infection. RESULTS: The cohort consisted of 230 individuals of which 75 (32.6%) patients were diagnosed with hematologic malignancies and 155 (67.4%) with solid tumors. At a median follow-up of 31 days after COVID-19 diagnosis, 38 (16.5%) patients had died due to COVID-19. Compared to survivors, patients who died were older (62.4 vs. 71.4 years, p < 0.001) and had a higher ECOG performance status (0.7 vs. 2.43, p < 0.001). Furthermore, higher neutrophil counts (64.9% vs. 73.8%, p = 0.03), lower lymphocyte counts (21.4% vs. 14%, p = 0.006) and lower albumin levels (32.5 g/l vs. 21.6 g/l, p < 0.001) were observed to be independent risk factors for adverse outcomes. No association between mortality and systemic antineoplastic therapy was found (p > 0.05). In 60.6% of the patients, therapy was postponed due to quarantine requirements or hospital admission. CONCLUSION: Mortality of Austrian cancer patients infected with SARS-CoV­2 is comparable to that of other countries. Furthermore, risk factors associated with higher mortality were evident and similar to the general population. Treatment delays were frequently observed.

The frequency of differentiated CD3+CD27-CD28- T cells predicts response to CART cell therapy in diffuse large B-cell lymphoma.

Background: Chimeric antigen receptor T (CART) cell therapy targeting the B cell specific differentiation antigen CD19 has shown clinical efficacy in a subset of relapsed/refractory (r/r) diffuse large B cell lymphoma (DLBCL) patients. Despite this heterogeneous response, blood pre-infusion biomarkers predicting responsiveness to CART cell therapy are currently understudied. Methods: Blood cell and serum markers, along with clinical data of DLBCL patients who were scheduled for CART cell therapy were evaluated to search for biomarkers predicting CART cell responsiveness. Findings: Compared to healthy controls (n=24), DLBCL patients (n=33) showed significant lymphopenia, due to low CD3+CD4+ T helper and CD3-CD56+ NK cell counts, while cytotoxic CD3+CD8+ T cell counts were similar. Although lymphopenic, DLBCL patients had significantly more activated HLA-DR+ (P=0.005) blood T cells and a higher frequency of differentiated CD3+CD27-CD28- (28.7 ± 19.0% versus 6.6 ± 5.8%; P<0.001) T cells. Twenty-six patients were infused with CART cells (median 81 days after leukapheresis) and were analyzed for the overall response (OR) 3 months later. Univariate and multivariate regression analyses showed that low levels of differentiated CD3+CD27-CD28- T cells (23.3 ± 19.3% versus 35.1 ± 18.0%) were independently associated with OR. This association was even more pronounced when patients were stratified for complete remission (CR versus non-CR: 13.7 ± 11.7% versus 37.7 ± 17.4%, P=0.001). A cut-off value of ≤ 18% of CD3+CD27-CD28- T cells predicted CR at 12 months with high accuracy (P<0.001). In vitro, CD3+CD8+CD27-CD28- compared to CD3+CD8+CD27+CD28+ CART cells displayed similar CD19+ target cell-specific cytotoxicity, but were hypoproliferative and produced less cytotoxic cytokines (IFN-γ and TNF-α). CD3+CD8+ T cells outperformed CD3+CD4+ T cells 3- to 6-fold in terms of their ability to kill CD19+ target cells. Interpretation: Low frequency of differentiated CD3+CD27-CD28- T cells at leukapheresis represents a novel pre-infusion blood biomarker predicting a favorable response to CART cell treatment in r/r DLBCL patients.

Functional Precision Medicine Provides Clinical Benefit in Advanced Aggressive Hematologic Cancers and Identifies Exceptional Responders.

Personalized medicine aims to match the right drug with the right patient by using specific features of the individual patient's tumor. However, current strategies of personalized therapy matching provide treatment opportunities for less than 10% of patients with cancer. A promising method may be drug profiling of patient biopsy specimens with single-cell resolution to directly quantify drug effects. We prospectively tested an image-based single-cell functional precision medicine (scFPM) approach to guide treatments in 143 patients with advanced aggressive hematologic cancers. Fifty-six patients (39%) were treated according to scFPM results. At a median follow-up of 23.9 months, 30 patients (54%) demonstrated a clinical benefit of more than 1.3-fold enhanced progression-free survival compared with their previous therapy. Twelve patients (40% of responders) experienced exceptional responses lasting three times longer than expected for their respective disease. We conclude that therapy matching by scFPM is clinically feasible and effective in advanced aggressive hematologic cancers. SIGNIFICANCE: This is the first precision medicine trial using a functional assay to instruct n-of-one therapies in oncology. It illustrates that for patients lacking standard therapies, high-content assay-based scFPM can have a significant value in clinical therapy guidance based on functional dependencies of each patient's cancer.See related commentary by Letai, p. 290.This article is highlighted in the In This Issue feature, p. 275.

How I manage autoimmune cytopenias in patients with lymphoid cancer.

Autoimmune conditions can occur in a temporary relationship with any malignant lymphoma. In many instances, treatment at diagnosis is not required, but symptomatic autoimmune conditions represent an indication for treatment, particularly in chronic lymphoproliferative diseases. Treatment is selected depending on the predominant condition: autoimmune disease (immunosuppression) or lymphoma (antilymphoma therapy). Steroids and anti-CD20 antibodies are effective against both conditions and may suppress the autoimmune complication for a prolonged period. The efficacy of B-cell receptor inhibitors has provided us with novel insights into the pathophysiology of antibody-producing B cells. Screening for underlying autoimmune conditions is part of the lymphoma workup, because other drugs, such as immunomodulators and checkpoint inhibitors, should be avoided or used with caution. In this article, we discuss diagnostic challenges and treatment approaches for different situations involving lymphomas and autoimmune cytopenias.

Influence of TP53 Mutation on Survival of Diffuse Large B-Cell Lymphoma in the CAR T-Cell Era.

Refractory/relapsed diffuse large B-cell lymphoma (DLBCL) is associated with poor outcome. The clinical behavior and genetic landscape of DLBCL is heterogeneous and still not fully understood. TP53 mutations in DLBCL have been identified as markers of poor prognosis and are often associated with therapeutic resistance. Chimeric antigen receptor T-cell therapy is an innovative therapeutic concept and represents a game-changing therapeutic option by supporting the patient's own immune system to kill the tumor cells. We investigated the impact of TP53 mutations on the overall survival of refractory/relapsed DLBCL patients treated with comparable numbers of therapy lines. The minimum number of therapy lines was 2 (median 4), including either anti-CD19 CAR T-cell therapy or conventional salvage therapy. A total of 170 patients with DLBCL and high-grade B-cell lymphoma with MYC, BCL2, and/or BCL6 rearrangements (DHL/THL), diagnosed and treated in our hospital between 2000 and 2021, were included. Twenty-nine of them received CAR T-cell therapy. TP53 mutations were found in 10/29 (35%) and 31/141 (22%) of patients in the CAR T-cell and conventional groups, respectively. Among the 141 patients not treated with CAR T cells, TP53 mutation was an independent prognostic factor for overall survival (OS) (median 12 months with TP53 vs. not reached without TP53 mutation, p < 0.005), but in the CAR T cell treated group, this significance could not be shown (median OS 30 vs. 120 months, p = 0.263). The findings from this monocentric retrospective study indicate that TP53 mutation status does not seem to affect outcomes in DLBCL patients treated with CAR T-cell therapy. Detailed evaluation in large cohorts is warranted.

Combined chemosensitivity and chromatin profiling prioritizes drug combinations in CLL.

The Bruton tyrosine kinase (BTK) inhibitor ibrutinib has substantially improved therapeutic options for chronic lymphocytic leukemia (CLL). Although ibrutinib is not curative, it has a profound effect on CLL cells and may create new pharmacologically exploitable vulnerabilities. To identify such vulnerabilities, we developed a systematic approach that combines epigenome profiling (charting the gene-regulatory basis of cell state) with single-cell chemosensitivity profiling (quantifying cell-type-specific drug response) and bioinformatic data integration. By applying our method to a cohort of matched patient samples collected before and during ibrutinib therapy, we identified characteristic ibrutinib-induced changes that provide a starting point for the rational design of ibrutinib combination therapies. Specifically, we observed and validated preferential sensitivity to proteasome, PLK1, and mTOR inhibitors during ibrutinib treatment. More generally, our study establishes a broadly applicable method for investigating treatment-specific vulnerabilities by integrating the complementary perspectives of epigenetic cell states and phenotypic drug responses in primary patient samples.

Aggressive B-cell lymphomas in patients with myelofibrosis receiving JAK1/2 inhibitor therapy.

Inhibition of Janus-kinase 1/2 (JAK1/2) is a mainstay to treat myeloproliferative neoplasms (MPN). Sporadic observations reported the co-incidence of B-cell non-Hodgkin lymphomas during treatment of MPN with JAK1/2 inhibitors. We assessed 626 patients with MPN, including 69 with myelofibrosis receiving JAK1/2 inhibitors for lymphoma development. B-cell lymphomas evolved in 4 (5.8%) of 69 patients receiving JAK1/2 inhibition compared with 2 (0.36%) of 557 with conventional treatment (16-fold increased risk). A similar 15-fold increase was observed in an independent cohort of 929 patients with MPN. Considering primary myelofibrosis only (N = 216), 3 lymphomas were observed in 31 inhibitor-treated patients (9.7%) vs 1 (0.54%) of 185 control patients. Lymphomas were of aggressive B-cell type, extranodal, or leukemic with high MYC expression in the absence of JAK2 V617F or other MPN-associated mutations. Median time from initiation of inhibitor therapy to lymphoma diagnosis was 25 months. Clonal immunoglobulin gene rearrangements were already detected in the bone marrow during myelofibrosis in 16.3% of patients. Lymphomas occurring during JAK1/2 inhibitor treatment were preceded by a preexisting B-cell clone in all 3 patients tested. Sequencing verified clonal identity in 2 patients. The effects of JAK1/2 inhibition were mirrored in Stat1-/- mice: 16 of 24 mice developed a spontaneous myeloid hyperplasia with the concomitant presence of aberrant B cells. Transplantations of bone marrow from diseased mice unmasked the outgrowth of a malignant B-cell clone evolving into aggressive B-cell leukemia-lymphoma. We conclude that JAK/STAT1 pathway inhibition in myelofibrosis is associated with an elevated frequency of aggressive B-cell lymphomas. Detection of a preexisting B-cell clone may identify individuals at risk.

Ultra-early response assessment in lymphoma treatment: [18F]FDG PET/MR captures changes in glucose metabolism and cell density within the first 72 hours of treatment.

PURPOSE: To determine whether, in patients with Hodgkin lymphoma (HL) or non-Hodgkin lymphoma (NHL), [18F]FDG PET/MR can capture treatment effects within the first week after treatment initiation, and whether changes in glucose metabolism and cell density occur simultaneously. METHODS: Patients with histologically proven HL or NHL were included in this prospective IRB-approved study. Patients underwent [18F]FDG PET/MR before, and then 48-72 h after (follow-up 1, FU-1) and 1 week after (FU-2) initiation of the first cycle of their respective standard chemotherapy (for HL) or immunochemotherapy (for NHL). Standardized [18F]FDG uptake values (SUVmax, SUVmean) and apparent diffusion coefficients (ADCmin, ADCmean) based on diffusion-weighted MRI, and metabolic and morphological tumour volumes (MTV, VOL) were assessed at each time-point. Multilevel analyses with an unstructured covariance matrix, and pair-wise post-hoc tests were used to test for significant changes in SUVs, ADCs, MTVs and VOLs between the three time-points. RESULTS: A total of 58 patients (11 with HL and 47 with NHL) with 166 lesions were analysed. Lesion-based mean rates of change in SUVmax, SUVmean, ADCmin, ADCmean, MTV and VOL between baseline and FU-1 were -46.8%, -33.3%, +20.3%, +14%, -46% and -12.8%, respectively, and between baseline and FU-2 were -65.1%, -49%, +50.7%, +32.4%, -61.1% and -24.2%, respectively. These changes were statistically significant (P < 0.01) except for the change in VOL between baseline and FU-1 (P = 0.079). CONCLUSION: In lymphoma patients, [18F]FDG PET/MR can capture treatment-induced changes in glucose metabolism and cell density as early as 48-72 h after treatment initiation.

Gender-Specific Aspects in Patients with Multiple Myeloma Undergoing Autologous Stem Cell Transplantation: A Single-Center Experience.

OBJECTIVE: Limited data exist on gender-specific aspects in hematologic malignancies and have been obtained mostly in non-Hodgkin lymphomas. The objective of this study was to investigate gender-specific aspects in patients with multiple myeloma (MM) undergoing autologous stem cell transplantation (ASCT). METHODS: A retrospective data analysis of 191 patients with MM who underwent ASCT was performed. Data collected from clinical records included age, sex, stage, induction therapy, outcome of induction, kind of stem cell mobilization, response to induction therapy and ASCT, cytogenetic aberrations, progression-free survival, and overall survival. RESULTS: Eighty-one patients (42%) were female, whereas 110 patients were male (58%). No differences between female and male patients could be observed according to the international staging system (ISS) (e.g. , ISS III: 14.8 vs. 17.3%), type of paraprotein, and cytogenetic aberrations (e.g., Del(13q): 32.7 vs. 28.9%). Five-year overall survival rates, when calculated from time to ASCT until death, were 27.2 and 36.4% and, when calculated from time to diagnosis until death, were 34.6 and 44.5%, respectively, and did not differ between groups according to ISS subgroups. CONCLUSION: Prognosis and baseline characteristics were identical and no differences could be observed between female and male patients with MM undergoing ASCT.

Lymphoma in Danon disease with chronic rhabdomyolysis treated with EPOCH-R: A case report.

Rare disorders often represent a challenge for clinicians and require close collaboration of an interdisciplinary team.We present the complex case of a 22-year-old male with Danon disease and late-onset of posttransplant lymphoproliferative disorder after heart transplantation. The critical aspects of his condition were: pre-existing rhabdomyolysis; infiltration of muscle and gut with lymphoma; advanced clinical stage with bulky disease; nonresponsiveness to the reduction of immunosuppression and rituximab monotherapy; expected cardiotoxicity of anthracyclines. Therefore, the patient was treated with the EPOCH-R protocol, which includes continuous administration of doxorubicin over 4 days, instead of R-CHOP, in which the anthracycline is given in a short single infusion. Complete remission was achieved after the third cycle; rhabdomyolysis did not increase and heart function was not affected. The patient received a total of 6 cycles and is still in metabolic complete remission.We conclude that patients with Danon disease can be treated with anthracycline-containing chemotherapy and that continuous infusion of EPOCH-R does not exacerbate pre-existing rhabdomyolysis.

What Makes a Good Palliative Care Physician? A Qualitative Study about the Patient's Expectations and Needs when Being Admitted to a Palliative Care Unit.

OBJECTIVE: The aims of the study were to examine a) patients' knowledge of palliative care, b) patients' expectations and needs when being admitted to a palliative care unit, and c) patient's concept of a good palliative care physician. METHODS: The study was based on a qualitative methodology, comprising 32 semistructured interviews with advanced cancer patients admitted to the palliative care unit of the Medical University of Vienna. Interviews were conducted with 20 patients during the first three days after admission to the unit and after one week, recorded digitally, and transcribed verbatim. Data were analyzed using NVivo 10 software, based on thematic analysis enhanced with grounded theory techniques. RESULTS: The results revealed four themes: (1) information about palliative care, (2) supportive care needs, (3) being treated in a palliative care unit, and (4) qualities required of palliative care physicians. The data showed that patients lack information about palliative care, that help in social concerns plays a central role in palliative care, and attentiveness as well as symptom management are important to patients. Patients desire a personal patient-physician relationship. The qualities of a good palliative care physician were honesty, the ability to listen, taking time, being experienced in their field, speaking the patient's language, being human, and being gentle. Patients experienced relief when being treated in a palliative care unit, perceived their care as an interdisciplinary activity, and felt that their burdensome symptoms were being attended to with emotional care. Negative perceptions included the overtly intense treatment. CONCLUSIONS: The results of the present study offer an insight into what patients expect from palliative care teams. Being aware of patient's needs will enable medical teams to improve professional and individualized care.

Cannabinoid Receptors Are Overexpressed in CLL but of Limited Potential for Therapeutic Exploitation.

The cannabinoid receptors 1 and 2 (CNR1&2) are overexpressed in a variety of malignant diseases and cannabinoids can have noteworthy impact on tumor cell viability and tumor growth. Patients diagnosed with chronic lymphocytic leukemia (CLL) present with very heterogeneous disease characteristics translating into highly differential risk properties. To meet the urgent need for refinement in risk stratification at diagnosis and the search for novel therapies we studied CNR expression and response to cannabinoid treatment in CLL. Expression levels of CNR1&2 were determined in 107 CLL patients by real-time PCR and analyzed with regard to prognostic markers and survival. Cell viability of primary CLL cells was determined in suspension and co-culture after incubation in increasing cannabinoid concentrations under normal and reduced serum conditions and in combination with fludarabine. Impact of cannabinoids on migration of CLL cells towards CXCL12 was determined in transwell plates. We found CNR1&2 to be overexpressed in CLL compared to healthy B-cells. Discriminating between high and low expressing subgroups, only high CNR1 expression was associated with two established high risk markers and conferred significantly shorter overall and treatment free survival. Viability of CLL primary cells was reduced in a dose dependent fashion upon incubation with cannabinoids, however, healthy cells were similarly affected. Under serum reduced conditions, no significant differences were observed within suspension and co-culture, respectively, however, the feeder layer contributed significantly to the survival of CLL cells compared to suspension culture conditions. No significant differences were observed when treating CLL cells with cannabinoids in combination with fludarabine. Interestingly, biologic activity of cannabinoids was independent of both CNR1&2 expression. Finally, we did not observe an inhibition of CXCL12-induced migration by cannabinoids. In contrast to other tumor entities, our data suggest a limited usability of cannabinoids for CLL therapy. Nonetheless, we could define CNR1 mRNA expression as novel prognostic marker.

Incidence of intensive care unit admission, outcome and post intensive care survival in patients with diffuse large B-cell lymphoma.

Some patients with diffuse large B-cell lymphoma (DLBCL) require intensive care unit (ICU) admission prior to or during chemotherapy. We analyzed all unscheduled ICU admissions in 331 consecutive patients (18-93 years) with newly diagnosed DLBCL. Thirty-seven patients (11.2%) required ICU treatment primarily due to hemodynamic (37.8%) or respiratory failure (24.3%). Bulky disease and high IPI score were predictive of ICU admission in the early course. ICU and hospital survival was 75.7% and 70.3%, respectively. Overall survival in ICU patients with newly diagnosed DLBCL was worse compared to non-ICU-patients (40.7% vs. 72.7% at two years). However, survival of high-risk patients (IPI 3-5), continuous complete remission, and disease-free survival did not differ. Post-ICU survival was poor in patients with relapsed/refractory DLBCL (0.1-10 months). Our observations favor unrestricted ICU support in DLBCL patients undergoing first-line therapy. ICU referral of patients with refractory/relapsed disease must be evaluated in the context of the hematologic prognosis.

Impact of Single or Combined Genomic Alterations of TP53, MYC, and BCL2 on Survival of Patients With Diffuse Large B-Cell Lymphomas: A Retrospective Cohort Study.

MYC and BCL2 translocations as well as TP53 deletion/mutation are known risk factors in diffuse large B-cell lymphoma (DLBCL) but their interplay is not well understood.In this retrospective cohort study, we evaluated the combined prognostic impact of TP53 deletion and mutation status, MYC and BCL2 genomic breaks in tumor samples of 101 DLBCL patients. The cohort included 53 cases with MYC rearrangements (MYC+).TP53 deletions/mutations (TP53+) were found in 32 of 101 lymphomas and were equally distributed between MYC+ and MYC- cases (35.8% vs. 27.1%). TP53+ lymphomas had lower responses to treatment than TP53- (complete remission 34.4% vs. 60.9%; P = 0.01). TP53 alteration was the dominant independent prognostic factor in multivariate analysis (P = 0.01). Overall survival (OS) varied considerably between subgroups with different genomic alterations: Patients with sole MYC translocation, and interestingly, with triple MYC+/BCL2+/TP53+ aberration had favorable outcomes (median OS not reached) similar to patients without genomic alterations (median OS 65 months). In contrast, patients with MYC+/BCL2+/TP53- double-hit lymphomas (DHL) (28 months), MYC+/BCL2-/TP53+ lymphomas (10 months) or sole TP53 mutation/deletion (12 months) had a poor median OS. Our findings demonstrate differences in OS of DLBCL patients depending on absence or presence of single or combined genetic alterations of MYC, BCL2, and TP53. Cooccurrence of TP53 and BCL2 aberrations ameliorated the poor prognostic impact of single TP53+ or BCL2+ in MYC positive patients.This pilot study generates evidence for the complex interplay between the alterations of genetic pathways in DLBCL, which goes beyond the concept of DHL. The variable survival of DLBCL patients dependent on single or combined alterations in the TP53, MYC, and BCL2 genes indicates the need for comprehensive genomic diagnosis.

Evaluation of Diffusion-Weighted Magnetic Resonance Imaging for Follow-up and Treatment Response Assessment of Lymphoma: Results of an 18F-FDG-PET/CT-Controlled Prospective Study in 64 Patients.

PURPOSE: To determine the value of diffusion-weighted MRI (DWI-MRI) for treatment response assessment in 2-[18F]fluoro-2-deoxy-D-glucose (FDG)-avid lymphoma. EXPERIMENTAL DESIGN: Patients with FDG-avid Hodgkin (HL) or non-Hodgkin lymphoma (NHL) at pretherapeutic 18F-FDG-PET/CT, who had also undergone pretherapeutic whole-body DWI-MRI, were included in this prospective study. Depending on the histologic lymphoma subtype, patients received different systemic treatment regimens, and follow-up DWI-MRI and 18F-FDG-PET/CT were performed at one or more time points, depending on the clinical course. For each follow-up DWI-MRI, region-based rates of agreement, and rates of agreement in terms of treatment response (complete remission, partial remission, stable disease, or progressive disease), relative to the corresponding 18F-FDG-PET/CT, were calculated. RESULTS: Sixty-four patients were included: 10 with HL, 22 with aggressive NHL, and 32 with indolent NHL. The overall region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.4%. For the 51 interim examinations (performed after 1-3 therapy cycles), region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.2%, and for the 48 end-of-treatment examinations, agreement was 99.8%. No significant differences, in terms of region-based agreement between DWI-MRI and 18F-FDG-PET/CT, were observed between the three lymphoma groups (HL, aggressive NHL, indolent NHL; P = 0.25), or between interim and end-of-treatment examinations (P = 0.21). With regard to treatment response assessment, DWI-MRI agreed with 18F-FDG-PET/CT in 99 of 102 follow-up examinations (97.1%), with a κ value of 0.94 (P < 0.0001). CONCLUSIONS: In patients with FDG-avid lymphoma, DWI-MRI may be a feasible alternative to 18F-FDG-PET/CT for follow-up and treatment response assessment.

Evaluation of diffusion-weighted MRI for pretherapeutic assessment and staging of lymphoma: results of a prospective study in 140 patients.

PURPOSE: To determine the value of diffusion-weighted MRI (DWI-MRI) for pretherapeutic imaging of fluorodeoxyglucose (FDG)-avid lymphoma and lymphoma with variable FDG avidity. EXPERIMENTAL DESIGN: Treatment-naïve patients with lymphoma who were referred for whole-body staging were included in this prospective study. Group A included patients with FDG-avid lymphoma (e.g., Hodgkin, diffuse large B-cell, and follicular lymphoma), whereas Group B included patients with lymphoma of variable FDG avidity [e.g., extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT)]. All patients underwent DWI-MRI and 18F-FDG- positron emission tomography/computed tomography (PET/CT). Region-based sensitivity and agreement with Ann Arbor staging, relative to the reference standard, were calculated for DWI-MRI, and, in Group B, also 18F-FDG-PET/CT and contrast-enhanced (CE-) CT. RESULTS: In Group A (100 patients), DWI-MRI had a region-based sensitivity of 97%, and with regard to staging, agreed with the reference standard in 94 of 100 patients (κ, 0.92). In Group B (40 patients; 38 MALT lymphomas and 2 small lymphocytic lymphomas/chronic lymphocytic leukemias), DWI-MRI, 18F-FDG-PET/CT, and CE-CT had region-based sensitivities of 94.4%, 60.9%, and 70.7%, respectively. With regard to staging in Group B, DWI-MRI, 18F-FDG-PET/CT, and CE-CT agreed with the reference standard in 37 of 40, 26 of 40, and 24 of 40 patients, with κ values of 0.89, 0.52, and 0.43, respectively. CONCLUSIONS: In patients with FDG-avid lymphoma, DWI-MRI seems to be only slightly inferior to 18F-FDG-PET/CT with regard to pretherapeutic regional assessment and staging. In patients with lymphoma subtypes that show a variable FDG avidity (e.g., MALT lymphoma), DWI-MRI seems to be superior to both 18F-FDG-PET/CT and CE-CT.