Prognostic impact of nodal involvement in Waldenström macroglobulinaemia.

The clinical and prognostic implications of nodal involvement (NI) in Waldenström macroglobulinaemia (WM) are largely unknown. In this study, we explored the impact of NI on clinical presentation and outcome in a population-based cohort of 469 patients with WM, consecutively diagnosed between 2000 and 2022. NI was detected in 34% of patients and was associated with symptomatic disease, adverse prognostic factors, an increased risk of transformation, and lymphoma-related death. Our findings indicate that NI is of prognostic significance in WM, suggesting a need for enhanced surveillance in these patients.

Routine Histopathology of Tonsillectomy Specimens, Is It Necessary? A Prospective Observational Study.

Routine histopathology of tonsillectomy specimens is not standard practice due to cost and resource constraints. This study aimed to evaluate the prevalence of abnormal histopathologies in tonsillectomy specimens to determine the necessity of routine histopathology. A prospective observational study was conducted from January 2014 to August 2016 at a general tertiary care center after approval of Institutional Ethics Committee (IEC). Patients scheduled for tonsillectomy surgery as per the AAOHNS 2011 criteria were included in the study. All tonsillectomy specimens were sent for histopathology, and abnormal findings were documented. Statistical analysis was performed. A total of 111 patients were enrolled in this study, and 222 tonsillectomy specimens were analyzed. The most common finding was chronic tonsillitis, which justified the selection criteria in 91.89% of patients. Two patients with chronic tonsillitis were also found to have actinomycosis present on the surface without parenchymal tissue reaction. Abnormal histopathological findings were observed in 9 (8.10%) of patients, leading to further investigations or treatment in 8 cases. These abnormalities included chronic granuloma, non-Hodgkin's lymphoma, early squamous cell carcinoma, and one choristoma. Tonsillar asymmetry, recent onset of symptoms and older age were found to be significantly correlated with abnormal histopathology and malignancy. Routine histopathology in tonsillectomy specimens helps to identify important findings that may require additional treatment. Based on the study we strongly recommend routine histopathology of tonsillectomy specimen. When significant cost constraints exist, risk-based approach can be adopted. Factors such as older age, asymmetry of tonsils, referred otalgia, duration of symptoms (recent onset) and a history of addiction should be considered for proceeding with histopathology. Supplementary Information: The online version contains supplementary material available at 10.1007/s12070-024-04888-1.

Mantle Cell Lymphoma in the Oral Cavity: Exploring the Differential Microscopic Diagnosis of a Rare Case.

Mantle cell lymphoma (MCL) is a rare subtype of B-cell non-Hodgkin's lymphoma (NHL), which generally has an aggressive course. Its pathophysiology seems to be related with the malignant transformation of B-cell mantle zone lymphocytes due to the CCND1 rearrangement. The occurrence of MCL in the oral cavity is especially rare. In this report, we present an exceptional case of oral MCL diagnosed in the palate in a 56-year-old male patient, highlighting its distinct morphological and immunohistochemical features that may assist in the accurate diagnosis.

Higher Microbial Abundance and Diversity in Bronchus-Associated Lymphoid Tissue (BALT) Lymphomas than in Non-Cancerous Lung Tissues.

Purpose: It is well known that the majority of the extranodal marginal zone lymphomas of mucosa-associated lymphoid tissues (MALT lymphomas) are associated with microbiota, e.g., gastric MALT lymphoma with Helicobacter pylori. In general, they are very sensitive to low-dose radiotherapy and chemotherapeutic agents. The microbiota profile is not clearly elucidated in bronchus-associated lymphoid tissue (BALT) lymphoma, a rare type of MALT lymphoma in the lung. Thus, this study aimed to clarify the intratumor microbiome in BALT lymphoma using the third-generation NGS method. Materials and Methods: DNAs were extracted from 12 formalin-fixed paraffin-embedded (FFPE) tumor tissues obtained from BALT lymphoma patients diagnosed between 1990 and 2016. 16S rRNA gene was amplified by polymerase chain reaction. Amplicons were sequenced using a Nanopore platform. Next-generation sequencing analysis was performed to assess microbial profiles. For comparison, FFPE specimens from nine non-cancerous lung tissues were also analyzed. Results: Specific bacterial families including Burkholderiaceae, Bacillaceae, and Microbacteriaceae were associated with BALT lymphoma by a linear discriminant analysis effect size approach. Although the number of specimens was limited, BALT lymphomas exhibited significantly higher microbial abundance and diversity with distinct microbial composition patterns and correlation networks than non-cancerous lung tissues. Conclusion: This study provides the first insight into intratumor microbiome in BALT lymphoma using the third-generation NGS method. A distinct microbial composition suggests the presence of a unique tumor microenvironment of BALT lymphoma.

Fibrin associated large B-cell lymphoma accidentally identified in a breast implant capsule: a molecular report of a rare entity.

Breast implant-associated (BIA) lymphoma is a rare malignancy, typically originating from T-cells; however, few cases of diffuse large B-cell lymphoma (LBCL) have been recently described. These cases share major features: Epstein-Barr virus positivity and a favorable prognosis with surgical intervention alone, hinting at a potential link to fibrin-associated LBCL (FA-LBCL). This study presents the first case of BIA-FA-LBCL in Italy and one of the few assessed from a molecular standpoint so far. We identified two pathogenic mutations in DNMT3A and a variant of uncertain significance (VUS) in JAK2. These findings suggest that dysfunctional epigenetic mechanisms and constitutive activation of the JAK-STAT pathway may underpin BIA-FA-LBCL lymphomagenesis. Finally, we summarized all the previously reported cases in alignment with the updated WHO-HAEM5 classification, shedding further light on the nature of this new entity. This report highlights the rarity of BIA-FA-LBCL and underscores the importance of comprehensive capsule sampling and reporting to national databases for accurate characterization and management of these lymphomas. The study supports the classification of BIA-FA-LBCL within the spectrum of FA-LBCL, emphasizing the need for further research to elucidate its molecular underpinnings and improve clinical outcomes.

Patient With a Diffuse Large B-Cell Non-Hodgkin Lymphoma in the Right Heart Chamber That Caused Cardiogenic Shock Was Well-Responded to Corticosteroids and Chemotherapy.

Heart tumors are sporadic. Secondary heart tumors are 30 times more common than primary ones. Depending on the location and origin of the tumor, clinical pictures vary from asymptomatic to severe manifestations such as arrhythmia, heart failure, pericardial effusion, and cardiogenic shock. We report hereby a rare case who presented with faint clinical symptoms, rapidly progressing to right heart failure within a month. Echocardiography and computed tomography of the chest revealed a tumor in the right heart chamber of 72.0 × 43.0 mm, in addition to large mediastinal lymph and left supraclavicular lymph nodes, cardiogenic shock appeared 4 days after admission. Through examination, it was suspected that this was a cardiac lymphoma. The patient was treated with 2 mg methylprednisolone per kg body weight. Symptoms of cardiogenic shock improved significantly and disappeared after 6 hours of treatment. After supraclavicular lymph node biopsy and immunohistochemistry, the final result was diagnosed as diffuse large B-cell non-Hodgkin lymphoma with large lymphoma in the right heart. The patient received chemotherapy with the R-CHOP regimen (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisolone). Re-examination before the 5th chemotherapy cycle showed no signs of right heart failure, normal self-activity, and no dyspnea on exertion, and the tumor size in the heart on the echocardiogram was 23.8 × 19.1 mm. The report shows that a large right heart tumor with a clinical picture of cardiogenic shock in a patient with diffuse large B-cell non-Hodgkin's lymphoma was well-responded to initial treatment with methylprednisolone at a dose of 2 mg/kg body weight and R-CHOP chemotherapy.

A Curious Case of Pericardial Effusion Diagnosed as Diffuse Large B-cell Lymphoma.

Lymphoma arises from mature B, T, and natural killer (NK) cells. Lymphomas are classified into Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL). Diffuse large B-cell lymphoma (DLBCL) is a type of NHL. It can present with symptoms such as fever, chills, or night sweats, as well as symptoms due to extranodal involvement. Extranodal sites can include the gastrointestinal tract or renal involvement. A higher risk of developing diffuse large B-cell lymphoma (DLBCL) is seen in patients with congenital or acquired immunodeficiency, those on immunosuppression, and those with autoimmune disorders. In this case report, we present a case of pericardial effusion that, upon further evaluation, was diagnosed as diffuse large B-cell lymphoma (DLBCL). A 64-year-old male presented with complaints of retrosternal chest pain that progressed from New York Heart Association (NYHA) Grade II to IV over a month. The chest pain was moderate intensity, dull aching, and non-radiating. It was associated with orthopnea, paroxysmal nocturnal dyspnea, and anasarca. A chest X-ray (posteroanterior {PA} view) showed cardiomegaly with an increased cardiothoracic ratio, mediastinal widening, and pulmonary congestion. Echocardiography revealed moderate non-tappable pericardial effusion. A high-resolution computed tomography (HRCT) chest scan showed moderate pericardial effusion and a homogeneous enhancing mass in the left anterior superior mediastinum. A computed tomography (CT)-guided biopsy was performed to check for lymphoma, thymoma, or tuberculosis. The patient was diagnosed with diffuse large B-cell lymphoma (DLBCL). Owing to the diverse manifestations of diffuse large B-cell lymphoma (DLBCL), prompt diagnosis is required for controlling disease progression.

A Rare Case of T-cell Lymphoblastic Lymphoma: A Diagnostic Predicament.

Lymphomas are the malignant neoplasms of lymphocytes and their precursor cells. Their diagnosis can sometimes be difficult due to their similarity to various other entities. A 10-year-old female reported swelling on the right side of the upper jaw for a month which was associated with mild continuous pain. On examination, a mild diffused swelling was noted on the right middle third of the face region which was firm in consistency and slightly tender. Intraorally, a firm tender swelling was noted on the right side of the hard palate. A proximal caries was noted with 55. A provisional diagnosis of dentoalveolar abscess with 55 was made. A panoramic radiograph showed loss of lamina dura concerning 11, 12, 53, 14, and 55, and loss of floor of the maxillary sinus. Cone-beam computed tomography and computed tomography-paranasal sinus revealed an ill-defined, hypodense osteolytic lesion with irregular borders extending from the 11 to 15 tooth region. Radiographic evaluation was suggestive of an infectious or neoplastic lesion. An incisional biopsy was performed and sent for histopathological and immunohistochemical analysis. A diagnosis of T-cell lymphoblastic lymphoma was made based on the features seen. The patient was sent for chemotherapy and radiotherapy. The reduction in the size of the lesion was noted on follow-up. Lymphoblastic lymphoma is a neoplasm of lymphocytes that is rarely seen in the oral cavity. Early diagnosis and prompt treatment are necessary to prevent further complications.

Chimeric antigen receptor T-cell therapy for haematological malignancies: Insights from fundamental and translational research to bedside practice.

Autologous chimeric antigen receptor (CAR) T-cell therapy has revolutionized the treatment of lymphoid malignancies, leading to the approval of CD19-CAR T cells for B-cell lymphomas and acute leukaemia, and more recently, B-cell maturation antigen-CAR T cells for multiple myeloma. The long-term follow-up of patients treated in the early clinical trials demonstrates the possibility for long-term remission, suggesting a cure. This is associated with a low incidence of significant long-term side effects and a rapid improvement in the quality of life for responders. In contrast, other types of immunotherapies require prolonged treatments or carry the risk of long-term side effects impairing the quality of life. Despite impressive results, some patients still experience treatment failure or ultimately relapse, underscoring the imperative to improve CAR T-cell therapies and gain a better understanding of their determinants of efficacy to maximize positive outcomes. While the next-generation of CAR T cells will undoubtingly be more potent, there are already opportunities for optimization when utilizing the currently available CAR T cells. This review article aims to summarize the current evidence from clinical, translational and fundamental research, providing clinicians with insights to enhance their understanding and use of CAR T cells.

Metabolic tumor volume and the survival of patients with Non-Hodgkin lymphoma treated with chimeric antigen receptor T cell therapy: a meta-analysis.

Background: Chimeric antigen receptor T cell (CAR-T) is a promising treatment for aggressive Non-Hodgkin lymphoma (NHL). The aim of the meta-analysis was to determine the association between metabolic tumor volumes (MTV) derived on positron emission tomography before CAR-T infusion and the survival of patients with NHL. Methods: Relevant observational studies pertaining to the purpose of the meta-analysis were obtained through a search of PubMed, Web of Science, and Embase from inception of the databases to April 1, 2024. The data was combined using a random-effects model that accounted for the potential influence of between-study heterogeneity. Results: Fifteen observational studies were included. Pooled results showed that compared to those with a lower MTV, the NHL patients with a higher MTV before CAR-T infusion were associated with a poor progression-free survival (hazard ratio [HR]: 1.73, 95% confidence interval [CI]: 1.48 to 2.02, p < 0.001; I2 = 20%) and overall survival (HR: 2.11, 95% CI: 1.54 to 2.89, p < 0.001; I2 = 58%). Subgroup analysis showed that the association between MTV and survival of NHL patients after CAR-T was not significantly impacted by study design, methods for determination of MTV cutoff, or analytic models (univariate or multivariate, p for each subgroup all < 0.05). Subgroup analysis suggested a stronger association between MTV and poor survival outcomes in patients with median of lines of previous treatment of 2 or 3 as compared to those of 4 (p for subgroup difference < 0.05). Further meta-regression analyses suggested that the association between MTV and survival was not significantly affected by sample size, age, proportion of men, cutoff value of MTV, follow-up duration, or study quality scores (p all > 0.05). Conclusion: A high MTV at baseline is associated with a poor survival of NHL patients after CAR-T. Systematic Review Registration: https://inplasy.com/, identifier INPLASY (INPLASY202450069).

Extra-Limbic Seronegative Encephalitis Preceding Recurrent Hodgkin's Lymphoma and Gastric Diffuse Large B-Cell Lymphoma: A Case Report.

We describe a patient with extra-limbic seronegative encephalitis with relapsing progressive course as the harbinger of sequential Hodgkin's lymphoma and Diffuse Large B-Cell lymphoma. Diagnosis of probable paraneoplastic neurologic syndrome (PNS) was arrived at by exhaustive elimination of alternative causes and supportive tissue diagnosis. This case highlights the phenotypic variety of paraneoplastic neurologic syndromes associated with hematologic malignancies and the challenges in their recognition, diagnosis, and treatment. We discuss and apply the updated consensus diagnostic criteria for paraneoplastic syndromes to our case as a means of bolstering probability in cases of diagnostic uncertainty.

Left ovarian mass revealing multivisceral lymphoma.

Lymphoma encompasses a range of cancers originating in the lymphatic system, categorized into Hodgkin lymphoma and non-Hodgkin lymphoma. Hodgkin lymphoma classically present as nodal disease, whereas non-Hodgkin lymphoma tends to involve extranodal regions. While it can be part of a systemic lymphoma, isolated nodal involvement is not uncommon. Extranodal lymphoma can affect virtually any organ or tissue, with the spleen, liver, gastrointestinal tract, pancreas, abdominal wall, genitourinary tract, adrenal glands, peritoneal cavity, and biliary tract being among the most commonly involved sites, in decreasing order of frequency. We present a case involving a 54-year-old woman presented with left iliac fossa pain. A sonography was performed, which showed left pelvic mass, magnetic resonance imaging showed left ovarian mass with enlargement of the cervix. Computed tomography revealed enlargement of the pancreas and adrenal glands, along with masses in the kidneys associated with extensive pathological lymph node enlargement in the para-aortic and pelvic regions. The patient underwent biopsy of a para-aortic lymph node, which revealed a diffuse large B cell lymphoma.

Nasal natural killer/T-cell lymphoma mimicking orbital cellulitis: A diagnostic dilemma.

Nasal natural killer/T-cell lymphoma (NK/TCL) is a rare form of malignant non-Hodgkin lymphoma (NHL) with a far more rare involvement of orbit. The orbital involvement has a highly variable clinical presentation. Here, we report one such case of a 40-year-old male patient who presented with swelling in the right upper and lower eyelids with the diminution of vision for 12 days. He had a history of blocked nose for two months. Clinical examination and CT scan of the orbit and paranasal sinuses suggested a diagnosis of right orbital cellulitis with pansinusitis. A combination of intravenous antibiotics was started, and functional endoscopic sinus surgery was done. Histopathology was a suggestive of nasal NK/TCLl NHL. After proper staging, the patient was given chemotherapy and radiotherapy. There was a complete resolution of mass with no recurrence over a follow-up of 10 months.

Non-Hodgkin's Lymphoma Within a Breast Abscess in a Male Patient: A Presentation and Literature Review of a Rare Case.

Breast abscesses are a common cause of presentation to the hospital. These should be treated with caution due to the possibility of rare pathology. We present a rare case of a 59-year-old diabetic gentleman who presented to the emergency department with a two-day history of a large right-sided breast swelling along with an area of induration, consistent with an abscess, extending to the right axillary region. Initial laboratory findings revealed elevated inflammatory markers. He was admitted for intravenous antibiotics. A computed tomography (CT) of the thorax performed on admission showed an ill-defined collection in the subcutaneous tissue of the right breast and axilla and an irregular right-sided peribronchial nodule with multiple enlarged pathological lymph nodes. This patient's case was discussed with tertiary specialist breast services and local respiratory teams. He underwent an ultrasound-guided right axillary lymph node biopsy. The histopathology of this revealed a high-grade malignant non-Hodgkin's lymphoma of the diffuse large B-cell (DLBCL) type. He was referred for a positron emission tomography (PET) scan and hematological oncology services for further treatment in the form of chemotherapy. This case presentation brings forward the importance of considering rare diagnoses and unusual histopathology when assessing a male breast lesion.

[Expression and diagnostic value of lymphocyte subsets and activation status in non-Hodgkin's lymphoma-associated hemophagocytic lymphohistiocytosis].

Objective: To determine the expression and diagnostic value of peripheral blood lymphocytes and functional activation status in non-Hodgkin lymphoma with hemophagocytic lymphohistiocytosis (NHL-HLH) . Methods: We retrospectively analyzed clinical data from 30 newly diagnosed NHL-HLH patients admitted to Jiangsu Province Hospital from September 2022 to September 2023. We assessed peripheral blood lymphocytes and activation status by flow cytometry. Forty newly diagnosed patients with NHL who received treatment at our hospital during the same period and had lymphocyte and functional activation indexes were selected as the control group. The differences in relative and absolute lymphocyte counts and functional activation indexes between the two groups were compared. The optimal cutoff values for continuous variables were calculated from the receiver operating characteristic curve and logistic regression analysis was used to evaluate the risk factors in NHL patients with HLH. Results: A total of 30 NHL-HLH patients were evaluated, including 12 T-cell lymphoma and 18 B-cell lymphoma patients. Forty individuals were in the control group, which included 19 T-cell lymphoma and 21 B-cell lymphoma patients. The absolute counts of CD3(+) T, CD4(+) T, CD8(+) T, and NK cells, along with the relative count of NK cells, were significantly lower in the HLH group compared with that in the control group (all P values<0.01) . The expression of CD38 and HLA-DR on CD8(+) T-cell activated subgroups was significantly higher in the NHL-HLH group compared with that in the control group (CD8(+)CD38(+)/CD8(+) T expression median: 57.4% vs 21.5%, P<0.001; CD8(+)CD38(+)/CD8(+) T expression median: 49.7% vs 33.5%, P=0.028, respectively) . In addition, CD28 expression on CD4(+) and CD8(+) T cells was significantly higher in NHL-HLH patients (P<0.01) . ROC curve and multivariate logistic regression analyses revealed that absolute NK cell count ≤72.0 cells/µl, CD4(+)CD28(+)/CD4(+) T >94.2%, and CD8(+)CD28(+)/CD8(+) T >38.4% were risk factors for predicting the occurrence of NHL-HLH patients. The sensitivity and specificity of the regression model were 86.7% and 86.1%, respectively, with an area under the curve of 0.94 (P<0.001) . Conclusions: In NHL patients with HLH, there was a significant reduction in the absolute number of peripheral blood lymphocyte subpopulations, whereas T-cell function was notably activated. Specifically, absolute counts of NK cells ≤72.0 cells/µl, CD4(+)CD28(+)/CD4(+) T >94.2%, and CD8(+)CD28(+)/CD8(+) T >38.4% were identified as risk factors for predicting the development of NHL-HLH patients. This will assist in early clinical diagnosis and treatment.

Acalabrutinib alone or in combination with rituximab for follicular lymphoma: An open-label study.

Acalabrutinib is a selective, second-generation Bruton tyrosine kinase inhibitor. In this open-label, parallel-group study, patients with relapsed/refractory (R/R) follicular lymphoma (FL) were randomised to either acalabrutinib monotherapy or acalabrutinib plus rituximab. An additional cohort of patients with treatment-naive (TN) FL received only the acalabrutinib-rituximab combination. Acalabrutinib-rituximab was well tolerated and active in R/R and TN FL; in the TN cohort the overall response rate was 92.3% with most remissions lasting over 4 years. Acalabrutinib monotherapy was also well tolerated and active in R/R FL. These results support further study of acalabrutinib alone and in combination with rituximab in FL.

How can we improve the successful identification of patients suitable for CAR-T cell therapy?

INTRODUCTION: In recent years, chimeric antigen receptor T (CAR-T) cell therapy has resulted in a breakthrough in the treatment of patients with refractory or relapsed hematological malignancies. However, the identification of patients suitable for CAR-T cell therapy needs to be improved. AREAS COVERED: CAR-T cell therapy has demonstrated excellent efficacy in hematological malignancies; however, views on determining when to apply CAR-T cells in terms of the evaluation of patient characteristics remain controversial. EXPERT OPINION: We reviewed the current feasibility and challenges of CAR-T cell therapy in the most common hematological malignancies and classified them according to the disease type and treatment priority, to guide clinicians and researchers in applying and investigating CAR-T cells furtherly.

When Maxillofacial CBCT Permits Fortuitously to Diagnose Primary Non-Hodgkin's Lymphoma: A Case Report.

A 47-year-old male with an unremarkable medical history was referred for atypical endodontic pain and treatment of his left upper molars. Clinical and radiographic examinations revealed an extensive, undefined osteolytic area around these teeth. A subsequent bone biopsy diagnosed diffuse large B-cell lymphoma, a high-grade non-Hodgkin's lymphoma. The hematology team prescribed six cycles of chemotherapy, supplemented by two cycles of methotrexate. Practitioners should be alerted by atypical tooth pain to consider 3D imaging to exclude malignant pathology as early as possible. Teaching point: An atypical tooth pain should alert the practitioner and guide them towards 3D imaging to eliminate diagnostic of malignant pathology as early as possible.

Leukemia in pregnancy: Diagnosis and therapeutic approach (Review).

The present study aimed to evaluate the epidemiological, diagnostic and therapeutic data of hematological malignancies in pregnancy. Leukemia in pregnancy is rare, and literature data are not extensive. Risk factors, epidemiology and pathogenesis of these diseases are not fully developed. Furthermore, there is a detailed report on the complications in pregnancy and the overall (per trimester) management of these diseases, specifically their treatment strategy. The possibility of achieving a future pregnancy in women with leukemia is described in the present study. The limited clinical research data currently available is mainly due to the inability to conduct randomized clinical trials for ethical reasons. Further research is needed, firstly due to the importance of these diseases for the pregnant woman and the fetus, and secondly, due to the continuous development of novel anticancer drugs that aim to improve the prognosis of these diseases.

Incidence of Central Nervous System Relapse in Primary Mediastinal Large B-Cell Lymphoma: Implications for Central Nervous System Prophylaxis.

BACKGROUND: Primary mediastinal large B-cell lymphoma (PMBCL) is an uncommon type of aggressive B-cell non-Hodgkin lymphoma. PMBCL shares some clinical and biologic features with nodular sclerosis classic Hodgkin lymphoma (cHL). Central nervous system (CNS) relapse is exceedingly rare in cHL. Therefore, it may be expected that CNS relapse in PMBCL is also uncommon. Herein, we examined the incidence of CNS relapse in patients with PMBCL treated with standard chemoimmunotherapy. PATIENTS AND METHODS: This retrospective single center analysis included 154 patients with newly diagnosed PMBCL seen at Mayo Clinic. The CNS relapse rate was calculated using a competing risk model, with death considered as a competing risk. RESULTS: With a median follow-up of 39 months, 3 patients experienced CNS relapse, all associated with systemic relapse. The cumulative incidence of CNS relapse for the entire cohort was 1.43% (95% CI, 0.3%-4.6%) at 1 year and 2.21% (95% CI, 0.6%-5.8%) at both 2 and 5 years. For those who did not receive CNS prophylaxis (n = 131), the incidence was 0.85% (95% CI, 0.1%-4.2%) at 1 year and 1.80% (95% CI, 0.3%-5.8%) at both 2 and 5 years. All 3 patients who experienced CNS relapse had R-CHOP as frontline therapy; 2 patients did not receive any CNS prophylaxis, while 1 patient received intrathecal CNS prophylaxis. CONCLUSION: The risk of CNS relapse in PMBCL appears to be very low after treatment with standard chemoimmunotherapy, suggesting routine CNS prophylaxis is not necessary.