CNS prophylaxis in lymphoma: Who to target and what therapy to use

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.

Secondary CNS Lymphoma in an Immunocompromised Patient: A Diagnostic Dilemma

Primary lymphoma can occur in the brain and is restricted to the central nervous system (CNS). Secondary lymphoma involves the CNS after affecting other organs in the body. The prognosis is worse for secondary CNS lymphoma. Early diagnosis and treatment are mandatory. We report a case of secondary CNS lymphoma that was misdiagnosed as a cerebral abscess because of its unusual features.

Diagnostics and treatment delay in primary central nervous system lymphoma: What the neurosurgeon should know

PURPOSE

The gold standard for diagnostics in primary central nervous system lymphoma (PCNSL) is histopathological diagnosis after stereotactic biopsy. Yet, PCNSL has a multidisciplinary diagnostic work up, which associated with diagnostic delay and could result in treatment delay. This article offers recommendations to neurosurgeons involved in clinical decision-making regarding (novel) diagnostics and care for patients with PCNSL with the aim to improve uniformity and timeliness of the diagnostic process for patients with PCNSL.

METHODS

We present a mini review to discuss the role of stereotactic biopsy in the context of novel developments in diagnostics for PCNSL, as well as the role for cytoreductive surgery.

RESULTS

Cerebrospinal fluid-based diagnostics are supplementary and cannot replace stereotactic biopsy-based diagnostics.

CONCLUSION

Histopathological diagnosis after stereotactic biopsy of the brain remains the gold standard for diagnosis. Additional diagnostics should not be a cause of diagnostic delay. There is currently no sufficient evidence supporting cytoreductive surgery in PCNSL, with recent studies showing contradictive data and suboptimal study designs.

Diffuse large B-cell lymphoma with contemporary involvement of central and peripheral nervous system: A case report and literature review

Introduction

Simultaneous involvement of the peripheral nervous system (PNS) and central nervous system (CNS) during the same period in diffuse large B-cell lymphoma (DLBCL) is rarely documented. In this particular case, the diagnosis of diffuse large B-cell lymphoma was pathologically confirmed, with invasion into the basal ganglia, diencephalon, and several peripheral nerves. The initial clinical manifestations were dyspnoea and hyperventilation.

Case presentation

The patient presented to the hospital with fatigue, dyspnoea, and limb pain for over 7 months, accompanied by progressive breathlessness and unconsciousness in the last 6 days. Initial treatment with glucocorticoids for Guillain-Barre syndrome (GBS) proved ineffective in controlling the severe shortness of breath and hyperventilation, necessitating the use of ventilator-assisted ventilation. 18-Fluorodeoxyglucose positron emission tomography/computed tomography (18FDG PET/CT) showed that the basal ganglia, brainstem, and multiple peripheral nerves were thickened and metabolically active. There were atypical cells in the cerebrospinal fluid; the pathology indicated invasive B-cell lymphoma, demonstrating a propensity toward diffuse large B-cell lymphoma (DLBCL). After receiving chemotherapy, the patient regained consciousness and was successfully weaned off ventilator assistance but died of severe pneumonia.

Discussion

The early clinical manifestations of DLBCL lack specificity, and multifocal DLBCL complicates the diagnostic process. When a single primary disease cannot explain multiple symptoms, the possibility of DLBCL should be considered, and nervous system invasion should be considered when nervous system symptoms are present. Once nervous system involvement occurs in DLBCL, whether the central or peripheral nervous system, it indicates a poor prognosis.

Irreversible Intrathecal Chemotherapy-induced Myelopathy in a Patient with Diffuse Large B-cell Lymphoma

Intrathecal chemotherapy is often administered for prophylaxis and treatment of central nervous system involvement in hematological malignancies. However, it may rarely cause neurotoxicity as a side effect. We herein report a 74-year-old woman with diffuse large B-cell lymphoma including a spinal lesion. She received systemic and intrathecal chemotherapy. After five doses of intrathecal chemotherapy, she developed intrathecal chemotherapy-induced myelopathy. Intrathecal treatment was discontinued, and she was administered vitamin B12 and folic acid, along with steroid pulses. However, her symptoms did not improve. Intrathecal chemotherapy-induced myelopathy is rare, but may be irreversible; therefore, clinicians should be aware of this potential complication.

How I treat secondary CNS involvement by aggressive lymphomas

Secondary central nervous system (CNS) lymphoma (SCNSL) is a rare but clinically challenging scenario with historically disappointing outcomes. SCNSL refers to lymphoma that has spread into the CNS concurrently with systemic disease or CNS relapse during or after frontline immunochemotherapy, presenting with or without systemic lymphoma. Diffuse large B-cell lymphoma (DLBCL) denotes the most common entity, but an increased incidence is observed in other histologies, such as Burkitt lymphoma and mantle-cell lymphoma. The incidence, timing in disease course, location, evidence supporting the use of CNS prophylaxis, and treatment pathways vary according to histology. No randomized data exist to delineate the best treatment approaches with current recommendations based on retrospective and single-arm studies. However, a regimen comprising immunochemotherapy, incorporating agents that cross the blood-brain barrier, followed by thiotepa-containing conditioning and autologous stem-cell transplant outlined in the international MARIETTA study demonstrated improvement in outcomes, representing a major accomplishment in the care of patients with DLBCL with SCNSL. Anti-CD19 chimeric antigen receptor T cell denotes a paradigm shift in the treatment of patients with systemic aggressive lymphomas, with emerging data also demonstrating efficacy without higher neurotoxicity in those with SCNSL. In this manuscript we discuss 5 clinical scenarios and review the evidence supporting our recommendations.

Central nervous system metastasis in a young female patient with primary mediastinal large B-cell lymphoma: A case report and literature review

BACKGROUND

Primary mediastinal B-cell lymphoma (PMBCL) is a subtype of diffuse large B-cell lymphoma that originates from a B cell in the thymus. It usually affects young female.

CASE DESCRIPTION

A 30-year-old woman presented with mediastinal mass with history of shortness of breath and chest pain. blood analysis showed low levels of hemoglobin, hematocrit, and mean corpuscular volume and high red cell distribution width. A computed tomography (CT)-guided mediastinal core biopsy disclosed primary mediastinal large B-cell lymphoma (PMLBL) with a nongerminal center phenotype and lung tissue infiltrate. Moreover, after undergoing six cycles of rituximab, cyclophosphamide, hydroxydaunomycin, Oncovin, and prednisone (R-CHOP) chemotherapy and mediastinal radiotherapy, the patient presented with headache and visual disturbance due to multiple supratentorial lesions.

CONCLUSION

Till date, only a few cases of central nervous system (CNS) metastasis have been reported in the literature. Moreover, CNS metastasis of refractory PMBCL is an uncommon event with a poor prognosis. Brain metastases are often the ultimate fatal consequence of many aggressive cancers, so early detection and treatment are important.

Neurosurgical Management of Central Nervous System Lymphoma: Lessons Learnt from a Neuro-Oncology Multidisciplinary Team Approach

Central nervous system lymphoma (CNSL) represents one of the most aggressive forms of extranodal lymphoma. The gold standard for CNSL diagnosis remains the stereotactic biopsy, with a limited role for cytoreductive surgery that has not been supported by historical data. Our study aims to provide a comprehensive overview of neurosurgery's role in the diagnosis of systemic relapsed and primary CNSL, with an emphasis on the impact on management and survival. This is a single center retrospective cohort study with data collected between August 2012 and August 2020, including patients referred with a potential diagnosis of CNSL to the local Neuro-oncology Multidisciplinary Team (MDT). The concordance between the MDT outcome and histopathological confirmation was assessed using diagnostic statistics. A Cox regression is used for overall survival (OS) risk factor analysis, and Kaplan-Meier statistics are performed for three prognostic models. The diagnosis of lymphoma is confirmed in all cases of relapsed CNSL, and in all but two patients who underwent neurosurgery. For the relapsed CNSL group, the highest positive predictive value (PPV) is found for an MDT outcome when lymphoma had been considered as single or topmost probable diagnosis. Neuro-oncology MDT has an important role in establishing the diagnosis in CNSL, not only to plan tissue diagnosis but also to stratify the surgical candidates. The MDT outcome based on history and imaging has good predictive value for cases where lymphoma is considered the most probable diagnosis, with the best prediction for cases of relapsed CNSL, questioning the need for invasive tissue diagnosis in the latter group.

Central Nervous System Progression/Relapse in Mature T- and NK-Cell Lymphomas

Non-Hodgkin lymphomas (NHL) are cancers of mature B-, T-, and NK-cells which display marked biological heterogeneity between different subtypes. Mature T- and NK-cell neoplasms are an often-aggressive subgroup of NHL and make up approximately 15% of all NHL. Long-term follow up studies have demonstrated that patients with relapsed/refractory disease have dismal outcomes; in particular, secondary central nervous system (CNS) involvement is associated with higher mortality, though it remains controversial whether this independently confers worse outcomes or if it simply reflects more aggressive systemic disease. Possible risk factors predictive of CNS involvement, such as an elevated lactate dehydrogenase and more than two sites of extranodal involvement, may suggest the latter, though several studies have suggested that discrete sites of anatomic involvement or tumor histology may be independent risk factors as well. Ultimately, small retrospective case series form the basis of our understanding of this rare but devastating event but have not yet demonstrated a consistent benefit of CNS-directed prophylaxis in preventing this outcome. Nonetheless, ongoing efforts are working to establish the epidemiology of CNS progression/relapse in mature T- and NK-cell lymphomas with the goal of identifying clinicopathologic risk factors, which may potentially help discern which patients may benefit from CNS-directed prophylactic therapy or more aggressive systemic therapy.

Sporadic Burkitt Lymphoma of the Thoracic and Lumbar Spinal Canal in an Adult: Oncogenicity and a Literature Review

Burkitt lymphoma (BL) is an aggressive form of lymphoma that occurs due to translocation of the c-myc proto-oncogene on chromosome 8. BL is characterized by three distinct groups: African/endemic variant, immunosuppressive variant, or sporadic variant. Most cases of the sporadic variant occur in patients less than 40 years of age with a median age of 30 at diagnosis and are primarily seen in Caucasians. An immunocompetent 69-year-old male presented with subacute onset weakness in the lower extremities. Magnetic resonance imaging (MRI) of the lumbar spine revealed a mass in the right paraspinal musculature with epidural extension, neural foraminal narrowing, and severe spinal canal stenosis in L2-L5. MRI of the thoracic spine revealed significant T5-T6 cord compression due to metastatic masses. Further diagnostic imaging revealed diffuse lymphadenopathy within the mediastinum and abdomen. Subsequently, the patient underwent a core needle biopsy of the left axillary lymph node, which revealed cluster of differentiation 20 and 10 (CD20 and CD10), c-myc, and B-cell lymphoma 6 (Bcl-6) positive lymphoid cells. A diagnosis of BL was made. The patient was treated with oral steroids and received one round of radiation therapy. The patient opted to forgo any antitumor treatment and was discharged to hospice. Primary lymphomas of the central nervous system (CNS) account for <5% of all CNS tumors. Approximately 5-10% of CNS lymphomas are recorded as BL, with the majority classified as high-grade B-cell lymphomas. Paraspinal involvement with BL is rare and not commonly seen in the sporadic variant.

Isolated CNS relapse of medullary aggressive high-grade B-cell lymphoma on 18F-FDG-PET/CT

This is a case of high-risk, aggressive, high-grade medullary B-cell lymphoma presenting with new onset of neurological dysfunction following initial complete response to the standard chemoimmunotherapy. A whole-body re-staging PET using fluorodeoxyglucose (¹⁸F-FDG) integrated with computed tomography (¹⁸FDG-PET/CT) performed with clinical suspicion of arachnoiditis, eloquently demonstrated unequivocal multifocal FDG uptake by the spinal cord without evidence of systemic recurrence, leading to a clinical diagnosis of secondary CNS lymphoma, which is a rare complication of DLBCL with ominous prognosis. Four cycles of Modified-MATRIX protocol resulted in a halt in fulminant course of the disease and the patient experienced slight reversal of the neurological deficits, although not deemed clinically fit for a repeat ¹⁸FDG-PET/CT due to his poor general well-being. Repeat MRI was suggestive of partial recovery, however. The clinical stability was proven short-lived, and the patient experienced progressive lower limb weakness only 3 weeks after discharge following his last cycle of treatment. Isolated CNS relapse of lymphoma is a rare occurrence in the literature. The CNS recurrence is more often leptomeningeal or confined to the brain parenchyma rather than the spinal cord. The role of ¹⁸FDG-PET/CT in the diagnostic algorithm of secondary CNS lymphoma is unclear and its significance in risk stratification and assessing the response to treatment has not been evaluated. This case report illustrates the imaging findings of a more unusual form of the disease with multifocal intramedullary involvement of the spinal cord, and highlights imaging features of this rare condition with ¹⁸FDG-PET/CT and MRI to support decision making in good clinical practice.

Multiparametric MR Imaging Features of Primary CNS Lymphomas

Objective

Primary central nervous system lymphomas (PCNS) are relatively rare tumors, accounting for about 4% of all brain tumors. On neuroimaging, they are characterized by a low MR signal in T1, isointense in T2, bright uniform contrast enhancement, and diffusion restriction. The aim of this study is to note the lack of effectiveness of the MR/CT perfusion technique in complex multiparametric imaging in the differential diagnosis of primary lymphomas of the central nervous system in comparison with highly malignant gliomas and brain metastases.

Materials and Methods

This prospective study included 80 patients with CNS tumors examined/operated at the Federal Center for Neurosurgery (Tyumen, Russia) from 2018 to 2021. The patients were divided into 4 groups: group 1 consisted of 33 cases with primary CNS lymphomas (10 cases with atypical manifestations according to perfusion parameters and 23 cases of classic CNS lymphomas), group 2 with anaplastic astrocytomas—14 cases, group 3—23 cases with glioblastomas and group 4—10 cases with solitary metastatic lesions. The study was carried out on a General Electric Discovery W750 3T magnetic resonance tomograph, a Canon Aquilion One multispiral X-ray computed tomograph (Gadovist 7.5 ml, Yomeron 400 mg−50 ml). Additionally, immunohistochemical analysis was carried out with the following markers: CD3, CD20, CD34, Ki-67, VEGF.

Results

It has been established that MR/CT perfusion is not a highly sensitive method for visualizing primary CNS lymphomas, as previously thought, but at the same time, the method has a number of undeniable advantages that make it indispensable in the algorithm of a complex multiparametric diagnostic approach for this type of tumor. Nevertheless, PLCNS is characterized by an atypical manifestation, which is an exception to the rule.

Conclusions

The possibilities of neuroimaging of primary lymphomas, even with the use of improved techniques for collecting MR/CT data, are limited and do not always allow reliable differentiation from other neoplasms.

Phase II Study of Gemcitabine, Peg-Asparaginase, Dexamethasone and Methotrexate Regimen for Newly Diagnosed Extranodal Natural Killer/T-Cell Lymphoma, Nasal Type: Final Analysis With Long-Term Follow-Up and Rational Research for the Combination

Patients with extranodal natural killer/T-cell lymphoma (ENKTL), nasal type are benefit from peg-asparaginase, gemcitabine, and methotrexate. Therefore, we conducted a prospective phase II trial using a combination of these drugs as GAD-M regimen in naïve ENKTL patients, simultaneously, explored the combinational mechanism. The GAD-M regimen was administered for 6 cycles sandwiched by radiotherapy for stage I/II and 6 cycles for stage III/IV patients. After 6 cycles, the overall response rate of 36 patients was 91.6%, and the complete remission rate increased to 83.3%. The 3-year progression-free survival (PFS) and overall survival (OS) rates were 74.8% and 77.8%, respectively. The 5-year PFS and OS were 68.3% and 77.8%. No patient suffered from the central nervous system (CNS) relapse. Most patients experienced recoverable liver dysfunction and anemia in this study. The plasma MTX concentration ratio at 12 to 24 hr during the first cycle could be an early predictor of outcomes in ENKTL (PFS, P=0.005; OS, P=0.002). Additionally, we found that high dose MTX (HD-MTX) and gemcitabine had the synergistic effect of ENKTL cell in vitro. Mechanistically, we demonstrated that the combination could lead to obviously apoptosis in ENKTL cell with extremely release of reactive oxygen spices (ROS), which mediated by endoplasmic reticulum stress. In conclusion, the GAD-M regimen could be a new choice to newly diagnosed ENKTL, especially for stage I/II patients. Furthermore, our results showed the synergy effect of HD-MTX with gemcitabine in ENKTL.

Clinical presentation of gastric Burkitt lymphoma presenting with paraplegia and acute pancreatitis: A case report

BACKGROUND

The incidence of gastric Burkitt lymphoma (BL), presenting as paraplegia and acute pancreatitis, is extremely low. BL is a great masquerader that presents in varied forms and in atypical locations, and it is prone to misdiagnosis and missed diagnosis. The prognosis of BL remains poor because of the difficulty in early diagnosis and the limited advances in chemotherapy.

CASE SUMMARY

A 53-year-old man was referred to our hospital from the local county hospital due to abdominal pain for two weeks and weakness in the lower extremities for one day. Magnetic resonance imaging of the abdomen and lumbar spine showed a swollen pancreas and gallbladder, with peripancreatic exudation and liquid collection, indicating acute pancreatitis and acute cholecystitis. Additionally, we observed abnormally thickened lesions of the gastric wall, multiple enlarged retroperitoneal lymph nodes and a well-demarcated, posterolateral extradural mass lesion between T9 and T12, with extension through the spinal foramen and definite bony destruction, suggesting metastasis in gastric malignancy. Subsequent whole-body positron emission tomography/computed tomography examination showed multifocal malignant lesions in the stomach, pancreas, gallbladder, bone, bilateral supraclavicular fossa, anterior mediastinum, bilateral axillary and retroperitoneal lymph nodes. Gastroduodenal endoscopy revealed primary BL with massive involvement of the gastric body and duodenum. The patient refused chemotherapeutic treatment and died one week later due to upper gastrointestinal hemorrhage. Afterward, we reviewed the characteristics of 11 patients with BL involving the stomach, pancreas or spinal cord.

CONCLUSION

Clinicians should be aware that BL can be the potential cause of acute pancreatitis or a rapidly progressive spinal tumor with accompanying paraplegia. For gastric BL, gastroscopy biopsies and pathology are necessary for a definite diagnosis.

Clinical and Therapeutic Implications of Epstein-Barr Virus in HIV-Related Lymphomas

The incidence of lymphomas is increased in people living with HIV (PLWH). Aggressive B-cell non-Hodgkin lymphomas (NHLs) are the most common and are considered an AIDS-defining cancer (ADC). Although Hodgkin lymphoma (HL) is not considered an ADC, its incidence is also increased in PLWH. Among all HIV-related lymphomas (HRL), the prevalence of Epstein-Barr virus (EBV) is high. It has been shown that EBV is involved in different lymphomagenic mechanisms mediated by some of its proteins, contributing to the development of different lymphoma subtypes. Additionally, cooperation between both HIV and EBV can lead to the proliferation of aberrant B-cells, thereby being an additional lymphomagenic mechanism in EBV-associated HRL. Despite the close relationship between EBV and HRL, the impact of EBV on clinical aspects has not been extensively studied. These lymphomas are treated with the same therapeutic regimens as the general population in combination with cART. Nevertheless, new therapeutic strategies targeting EBV are promising for these lymphomas. In this article, the different types of HRL are extensively reviewed, focusing on the influence of EBV on the epidemiology, pathogenesis, clinical presentation, and pathological characteristics of each lymphoma subtype. Moreover, novel therapies targeting EBV and future strategies to treat HRL harboring EBV are discussed.

The treatment of Burkitt lymphoma in adults

Burkitt lymphoma (BL) is a highly aggressive, B-cell, non-Hodgkin lymphoma categorized into endemic, sporadic, and immunodeficiency-associated subtypes. BL has distinct pathologic and clinical features, characterized by rapidly progressive tumors with high rates of extranodal involvement. Next-generation-sequencing analyses have further characterized the genomic landscape of BL and our understanding of disease pathogenesis, although these findings have yet to influence treatment. Although most patients are cured with intensive combination chemotherapy, given the paucity of randomized trials, optimal therapy has not been defined. Furthermore, treatment of elderly patients, patients with central nervous system involvement, or those with relapsed disease remains an unmet need. In this review, we highlight the clinical, pathologic, and genomic features, as well as standard and emerging treatment options for adult patients with BL.

Prognostic Factors, Survival Analyses and the Risk of Second Primary Cancer: A Population-Based Study on Burkitt Lymphoma/Leukemia

Burkitt lymphoma/leukemia (BL/L) is an aggressive oncohematological disease. This study evaluated the population-based prognosis and survival on BL/L as well as if BL/L behaved as a risk factor for the development of second primary cancers (SPCs) and if other first tumors behaved as risk factors for the occurrence of BL/L as an SPC. A retrospective cohort using the Surveillance, Epidemiology and End Results (SEER) Program (2008–2016) was performed. Kaplan–Meier, time-dependent covariate Cox regression and Poisson regression models were conducted. Overall, 3094 patients were included (median, 45 years; IQR, 22–62). The estimated overall survival was 65.4 months (95% CI, 63.6–67.3). Significantly more deaths occurred for older patients, black race, disease at an advanced stage, patients without chemotherapy/surgery and patients who underwent radiotherapy. Hodgkin lymphomas (nodal) (RR, 7.6 (3.9–15.0; p < 0.001)), Kaposi sarcomas (34.0 (16.8–68.9; p < 0.001)), liver tumors (3.4 (1.2–9.3; p = 0.020)) and trachea, mediastinum and other respiratory cancers (15.8 (2.2–113.9; p = 0.006)) behaved as risk factors for the occurrence of BL/L as an SPC. BL/L was a risk factor for the occurrence of SPCs as acute myeloid leukemias (4.6 (2.1–10.4; p < 0.001)), Hodgkin lymphomas (extranodal) (74.3 (10.0–549.8; p < 0.001)) and Kaposi sarcomas (35.1 (12.1–101.4; p < 0.001)). These results may assist the development of diagnostic and clinical recommendations for BL/L.

Development of next-generation tumor-homing induced neural stem cells to enhance treatment of metastatic cancers

Engineered tumor-homing neural stem cells (NSCs) have shown promise in treating cancer. Recently, we transdifferentiated skin fibroblasts into human-induced NSCs (hiNSC) as personalized NSC drug carriers. Here, using a SOX2 and spheroidal culture-based reprogramming strategy, we generated a new hiNSC variant, hiNeuroS, that was genetically distinct from fibroblasts and first-generation hiNSCs and had significantly enhanced tumor-homing and antitumor properties. In vitro, hiNeuroSs demonstrated superior migration to human triple-negative breast cancer (TNBC) cells and in vivo rapidly homed to TNBC tumor foci following intracerebroventricular (ICV) infusion. In TNBC parenchymal metastasis models, ICV infusion of hiNeuroSs secreting the proapoptotic agent TRAIL (hiNeuroS-TRAIL) significantly reduced tumor burden and extended median survival. In models of TNBC leptomeningeal carcinomatosis, ICV dosing of hiNeuroS-TRAIL therapy significantly delayed the onset of tumor formation and extended survival when administered as a prophylactic treatment, as well as reduced tumor volume while prolonging survival when delivered as established tumor therapy.

Phenotypical Characterization and Clinical Outcome of Canine Burkitt-Like Lymphoma

In dogs, Burkitt-like lymphoma (B-LL) is rare tumor and it is classified as a high-grade B-cell malignancy. The diagnosis is challenging because of the similar histologic appearance with other histotypes, no defined phenotypical criteria and poorly described clinical aspects. The aim of the study was to provide a detailed description of clinical and morphological features, as well as immunophenotypical profile of B-LL in comparison with the human counterpart. Thirteen dogs with histologically proven B-LL, for which a complete staging and follow-up were available, were retrospectively selected. Immunohistochemical expression of CD20, PAX5, CD3, CD10, BCL2, BCL6, MYC, and caspase-3 was evaluated. Histologically, all B-LLs showed a diffuse architecture with medium to large-sized cells, high mitotic rate and diffuse starry sky appearance. B-phenotype of neoplastic cells was confirmed both by flow-cytometry and immunohistochemistry. Conversely, B-LLs were negative for BCL2 and MYC, whereas some cases co-expressed BCL6 and CD10, suggesting a germinal center B-cell origin. Disease stage was advanced in the majority of cases. All dogs received CHOP-based chemotherapy with or without immunotherapy. Despite treatment, prognosis was poor, with a median time to progression and survival of 130 and 228 days, respectively. Nevertheless, ~30% of dogs survived more than 1 year. An increased apoptotic index, a high turnover index and caspase-3 index correlated with shorter survival. In conclusion, canine B-LL shows phenotypical differences with the human counterpart along with features that might help to differentiate this entity from diffuse large B-cell lymphoma.

DA-EPOCH-R therapy for high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements in a patient with renal dysfunction

High-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements, also known as double-hit lymphoma, has been reported as refractory to R-CHOP therapy and requires more intensive regimens. However, intensive and safe regimens for patients with renal dysfunction are unknown. Herein, we report the successful use of DA-EPOCH-R therapy for double-hit lymphoma in a 64-year-old man with renal dysfunction. The patient had lymphoma-induced bilateral ureteral obstruction. Although renal dysfunction remained after removing the obstruction using R-CHOP therapy, we completed six cycles of DA-EPOCH-R therapy without any major adverse events. DA-EPOCH-R therapy may be a safe regimen for renal dysfunction patients.

Recurrent small bowel obstruction caused by Burkitt lymphoma in an elderly man: a case report and review of the literature

BACKGROUND

Acute small bowel obstruction is a common surgical emergency usually caused by abdominal adhesions, followed by intraluminal tumors from metastatic disease. Although lymphomas have been known to cause bowel obstruction, Burkitt lymphoma is seldom reported to induce an obstruction in the adult population.

CASE PRESENTATION

A 78-year-old Hispanic man with a history of abdominal interventions presented to our hospital with abdominal pain. Computed tomography revealed a partial small bowel obstruction attributed to local inflammation or adhesions. Medical management with bowel rest and nasogastric decompression resulted in resolution of symptoms and quick discharge. He returned 2 days later with worsening abdominal pain. Repeat imaging showed progression of the partial small bowel obstruction, but with an additional 1.6-cm nodular density abutting the anterior aspect of the gastric antrum and lobulated anterior gastric antral wall thickening. He was taken to the operating room, where several masses were found. Intraoperative frozen sections were consistent with lymphoma, and pathology later revealed Burkitt lymphoma. Disease was found on both sides of the diaphragm by positron emission tomography. After the initial resection and adjuvant chemotherapy, the patient is alive and well about 14 months after resection.

CONCLUSIONS

Small bowel obstruction is uncommonly due to Burkitt lymphoma in the geriatric population and is more frequently seen in the pediatric and young adult populations. Burkitt lymphoma is very aggressive with rapid cell turnover leading to significant morbidity. The rapid recurrence of an acute abdominal process should prompt an investigation for a more sinister cause such as malignancy.

Quantitative proteomic analysis of cerebrospinal fluid from patients with diffuse large B-cell lymphoma with central nervous system involvement: A novel approach to diagnosis

The outcome of patients with diffuse large B-cell lymphoma (DLBCL) with central nervous system (CNS) recurrence is poor. However, there is currently no consensus regarding diagnostic techniques. The aim of the present study was to investigate the cerebrospinal fluid (CSF) protein profile of DLBCL and identify a potential novel method for the early diagnosis of patients with DLBCL at high risk for subsequent CNS involvement. The CSF proteomic profiling of patients with DLBCL and a control group were compared using label-free liquid chromatography-tandem mass spectrometry. Gene Ontology and pathway analyses were conducted using the Database for Annotation, Visualization and Integrated Discovery. The protein interactions were analyzed using the Search Tool for the Retrieval of Interacting Genes/Proteins database. In the present study, a total of 53 differentially expressed proteins with >1 log₂ fold change (false discovery rate <0.01, P<0.05) were identified and quantified. These proteins appeared to be involved in platelet degranulation, innate immune response and cell adhesion. Two hub gene network modules were obtained by protein-protein interaction network analysis. Of these proteins, secreted protein acidic and rich in cysteine (SPARC) and proenkephalin (PENK) were significantly decreased in the CSF of patients with DLBCL, which appeared to be correlated with CNS involvement. The findings of the present study indicate that decreased expression levels of SPARC and PENK in the CSF may serve as early-phase biomarkers to evaluate the risk of CNS involvement in patients with DLBCL, enabling clinicians to offer prophylactic therapy at the time of diagnosis.

Systemic HD-MTX for CNS prophylaxis in high-risk DLBCL patients: a prospectively collected, single-center cohort analysis

We evaluated the efficacy of systemic high-dose methotrexate (HD-MTX) for CNS prophylaxis in a prospectively recruited cohort of DLBCL patients at high risk of CNS relapse. High-risk CNS relapse was defined as the involvement of ≥ 2 extranodal sites with elevated lactate dehydrogenase (LDH); CNS international prognostic index (CNS-IPI) ≥ 4; or involvement of high-risk extranodal sites, including bone marrow, breasts, testes, and paranasal sinuses. Overall, 130 patients who received at least two cycles of standard chemoimmunotherapy were evaluated; of these, 64 patients received additional systemic HD-MTX, either on day 15 of alternating cycles or 2-5 weeks after completion of primary therapy. Patients receiving HD-MTX showed a generally higher risk of CNS relapse than the other 66 patients not receiving prophylaxis. The estimated 2-year cumulative CNS relapse, progression-free survival and overall survival rates were 8.1%, 66.3%, and 77.5%, respectively, in patients who received systemic HD-MTX and 6.9%, 67.4%, and 71.4%, respectively, in patients without prophylaxis, with no significant between-group differences. Although this study does not show that systemic HD-MTX is definitively effective, these results may be of help to other researchers investigating the utility of HD-MTX prophylaxis in mitigating negative risk factors.

An update on Burkitt lymphoma: a review of pathogenesis and multimodality imaging assessment of disease presentation, treatment response, and recurrence

Burkitt lymphoma (BL) is a highly aggressive, rapidly growing B cell non-Hodgkin lymphoma, which manifests in several subtypes including sporadic, endemic, and immunodeficiency-associated forms. Pathologically, BL is classically characterized by translocations of chromosomes 8 and 14 resulting in upregulation of the c-myc protein transcription factor with upregulation of cell proliferation. BL affects nearly every organ system, most commonly the abdomen and pelvis in the sporadic form. Imaging using a multimodality approach plays a crucial role in the management of BL from diagnosis, staging, and evaluation of treatment response to therapy-related complications with ultrasound, computed tomography, magnetic resonance imaging, and positron emission tomography playing roles. In this article, we review the pathobiology and classification of BL, illustrate a multimodality imaging approach in evaluating common and uncommon sites of involvement within the trunk and head and neck, and review common therapies and treatment-related complications.

Characteristics and outcomes of non-Hodgkin's lymphoma patients with leptomeningeal metastases

BACKGROUND

Leptomeningeal metastasis is an uncommon but devastating complication. The incidence of non-Hodgkin's lymphoma has been increasing in recent decades, due to the poor central nervous system penetration of drugs and the prolonged overall survival of patients, leptomeningeal metastases has gradually increased over time. Patients with leptomeningeal metastases have short survival durations and poor quality of life; there are few studies about non-Hodgkin's lymphoma with leptomeningeal metastases. We investigated characteristics and outcomes of non-Hodgkin's lymphoma patients with leptomeningeal metastases.

METHODS

This study included 27 non-Hodgkin's lymphoma patients with leptomeningeal metastases diagnosed at Tianjin Medical University Cancer Institute and Hospital between 2013 and 2016. Statistical analysis was performed to investigate the overall survival of non-Hodgkin's lymphoma with leptomeningeal metastases.

RESULTS

Diffuse large B cell lymphoma was the most common cancer subtype (21/27, 78%), and more than half of the patients showed extranodal involvement (18/27, 67%). Survival analysis has shown extranodal involvement (P = 0.0205), International Prognostic Index (P = 0.0112), performance status (P < 0.0001), parenchymal involvement (P = 0.0330) and received radiotherapy (P = 0.0056) were predictive factors of prognosis for these patients with leptomeningeal metastases. Cox regression analysis has shown patients with concurrent parenchymal involvement and received radiotherapy are correlated with good prognosis.

CONCLUSIONS

Given the small number of patients who were included, this study exhibited limitations with respect to analytical power and the random selection of patients. Nevertheless, this investigation revealed characteristics of non-Hodgkin's lymphoma patients with leptomeningeal metastases and suggested that such patients could benefit from multimodal therapy.

GESIDA/PETHEMA recommendations on the diagnosis and treatment of lymphomas in patients infected by the human immunodeficiency virus

The incidence of non-Hodgkin's lymphoma and Hodgkin's lymphoma is higher in patients with HIV infection than in the general population. Following the introduction of combination antiretroviral therapy (cART), the prognostic significance of HIV-related variables has decreased, and lymphoma-related factors have become more pronounced. Currently, treatments for lymphomas in HIV-infected patients do not differ from those used in the general population. However, differentiating characteristics of seropositive patients, such as the need for cART and specific prophylaxis and treatment of certain opportunistic infections, should be considered. This document updates recommendations on the diagnosis and treatment of lymphomas in HIV infected patients published by GESIDA/PETHEMA in 2008.

Secondary central nervous system lymphoma: spectrum of morphological MRI appearances

BACKGROUND

Secondary central nervous system lymphoma (SCNSL) is a rare and aggressive disease, which is defined as secondary central nervous system (CNS) involvement in patients with systemic lymphoma. According to previous reports, SCNSL presents mostly with leptomeningeal spread; however, our experience differs. In the present study, we demonstrate the diversity of magnetic resonance imaging (MRI) patterns in SCNSL.

PATIENTS AND METHODS

Initial morphological MRI findings in 21 patients (10 women and 11 men with mean age 62.3±16.2 years) with SCNSL were retrospectively evaluated. All patients suffered from neurological symptoms and underwent MRI, and all cases were histologically verified. Twelve patients were treated by corticosteroids at the time of the initial MRI.

RESULTS

Parenchymal lesions were present in 18 of 21 cases (85.7%), solitary meningeal infiltration was present in 1 patient (4.8%), leptomeningeal infiltration in combination with hypophyseal involvement in 1 patient (4.8%), and solitary involvement of the sixth cranial nerve (CN) was found in 1 patient (4.8%). Multiple lesions were present in 11 of 21 cases (52.4%). Diffusion restriction in all or part of the lesion was detected in 14 of 18 cases (77.8%). All parenchymal lesions had an infiltrative appearance and most enhanced homogenously (11 of 17 cases; 64.7%). A combination of parenchymal and meningeal involvement was found in 10 of 21 cases (47.6%). Infiltration of the CNs, basal ganglia, corpus callosum, and ependyma was present in 8 of 21 cases (38.1%) for each of the abovementioned structures; hypothalamic-hypophyseal axis was affected in 7 of 21 cases (33.3%).

CONCLUSION

In contrast to previous reports, SCNSL presented as parenchymal disease. MRI is not sufficient for differentiation between primary and secondary CNS lymphoma.

Secondary central nervous system lymphoma surrounding a region injured by subarachnoid hemorrhage and subsequent aneurysmal clipping

The present case study describes a rare case of secondary central nervous system (CNS) lymphoma that infiltrated the dura and leptomeninges around the area injured by subarachnoid hemorrhage and subsequent aneurysmal clipping. Invasion of the CNS was observed by computed tomography as slurred fissures of the right parietal lobe adjacent to the surgery area. Subdural and subarachnoid enhancement overlapping the area injured by past surgical procedures was observed by contrast-enhanced magnetic resonance imaging. Surgical resection revealed B-cell lymphoma infiltrating the dura and leptomeninges surrounding the post-hemorrhagic area. The patient was subsequently diagnosed with systemic lymphoma and bone marrow invasion, and multiple lymph node swelling. To the best of our knowledge, this is the first report of malignant lymphoma involving the CNS overlapping a previously injured area.

Secondary Central Nerve System Lymphoma With Intratumoral Hemorrhage Suggested as Intravascular Lymphoma by Autopsy: A Case Report

Intravascular large B-cell lymphoma (IVL) is a rare type of extranodal diffuse large B-cell lymphoma (DLBCL), which often infiltrates the central nervous system (CNS) during the clinical course. Cerebral hemorrhage in patients with CNS lymphoma at presentation is rare. Herein, we describe a case of secondary CNS lymphoma with intratumoral hemorrhage, which was suggested as IVL from autopsy findings. A 76-year-old Japanese man with a history of treatment for B-cell non-Hodgkin’s lymphoma was transferred to our hospital in an ambulance for generalized convulsions. Brain CT scan revealed a high-density tumor with edema and intratumoral hemorrhage in the left temporal lobes. He died in a rapid course, and autopsy revealed a focal hemorrhage with diffuse infiltration of lymphoma cells in the left temporal lobe and findings suggestive of IVL. Furthermore, the autopsy revealed a discrepancy in the CD20 immunostaining of lymphoma cells between the brain and other organs. Clinicians should not eliminate CNS lymphoma from the differential diagnosis of intracranial tumor with hemorrhage. Although many patients with IVL have rapidly progressive courses, it is very important to diagnose IVL at the initial onset, even in serious situations, to consider CNS prophylaxis.

Neuroimaging in Central Nervous System Lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare aggressive high-grade type of extranodal lymphoma. PCNSL can have a variable imaging appearance and can mimic other brain disorders such as encephalitis, demyelination, and stroke. In addition to PCNSL, the CNS can be secondarily involved by systemic lymphoma. Computed tomography and conventional MRI are the initial imaging modalities to evaluate these lesions. Recently, however, advanced MRI techniques are more often used in an effort to narrow the differential diagnosis and potentially inform diagnostic and therapeutic decisions.

Case-based review: primary central nervous system lymphoma

Primary CNS lymphoma (PCNSL) is a rare diffuse large B-cell lymphoma originating within the central nervous system. The overall incidence of PCNSL is rising, particularly in the elderly population. Immunosuppression is a strong risk factor, but most patients with this tumor are apparently immunocompetent. Diagnosis of PCNSL can be challenging. Non-invasive or minimally invasive tests such as ophthalmological evaluation and spinal fluid analysis may be useful, but the majority of patients require tumor biopsy for definitive diagnosis. Our knowledge concerning optimum treatment of PCNSL is fragmentary due to paucity of adequately sized trials. Most patients are now initially treated with high-dose-methotrexate-based chemotherapy alone, as the addition of whole-brain radiotherapy at standard doses has not been shown to increase survival and does increase the risk of neurological toxicity. Ongoing trials are addressing issues such as the roles of reduced-dose radiotherapy, the addition of the CD20 antibody rituximab to chemotherapy, high-dose chemotherapy followed by autologous stem cell transplantation, and maintenance therapy in the primary management of PCNSL.

Usefulness of Flow Cytometric Analysis for Detecting Leptomeningeal Diseases in Non-Hodgkin Lymphoma

BACKGROUND

The clinical usefulness of flow cytometry (FCM) for the diagnosis of leptomeningeal diseases (LMD) in non-Hodgkin lymphomas has been suggested in previous studies but needs to be further validated. With this regards, we evaluated the use of FCM for LMD in a series of Korean patients with non-Hodgkin lymphoma.

METHODS

FCM and cytomorphology were conducted using samples obtained from clinically suspected LMD patients, follow-up LMD patients, and those with high risk of developing tumorigenic diseases. We then compared results of FCM and cytomorphology. In total, 55 and 47 CSF samples were analyzed by FCM and cytomorphology, respectively.

RESULTS

Of the samples analyzed, 25.5% (14/55) and 12.8% (6/47) were positive by FCM and cytomorphology, respectively. No samples were determined as negative by FCM but positive by cytomorphology. Seven patients were positive only by FCM and negative by cytomorphology, and six among them were clinically confirmed to have LMD either by follow-up cytomorphology or imaging study.

CONCLUSIONS

We observed a high detection rate of tumor cells by FCM compared with cytomorphology. FCM study can be useful in early sensitive detection of LMD.

Minimally Invasive Diagnosis of Secondary Intracranial Lymphoma

Diffuse large B cell lymphomas (DLBCL) are an aggressive group of non-Hodgkin lymphoid malignancies which have diverse presentation and can have high mortality. Central nervous system relapse is rare but has poor survival. We present the diagnosis of primary mandibular DLBCL and a unique minimally invasive diagnosis of secondary intracranial recurrence. This case highlights the manifold radiological contributions to the diagnosis and management of lymphoma.

Intraocular Relapse with Hypopyon and Retinal Infiltrates after Chemotherapy and Peripheral Blood Stem Cell Transplantation for Extranodal NK/T-Cell Lymphoma

We report a case of intraocular relapse of extranodal NK/T-cell lymphoma with anterior chamber hypopyon and retinal infiltrates. A 55-year-old man developed fever, malaise, anorexia, and hepatosplenomegaly, and was diagnosed with NK/T-cell lymphoma by liver biopsy. He underwent 2 courses of SMILE (dexamethasone, methotrexate, ifosfamide, L-asparaginase, and etoposide) chemotherapy, followed by myeloablative peripheral blood stem cell transplantation, donated by his brother. Two months later, he developed high-grade fever, hepatosplenomegaly, and peritoneal lymphadenopathy, and the relapse with hemophagocytic syndrome was diagnosed by bone marrow biopsy. He underwent 2 courses of SMILE salvage chemotherapy, followed by non-myeloablative peripheral blood stem cell transplantation, donated by his son. Two months later, he noticed blurred vision in both eyes. The right eye had aqueous cells and keratic precipitates, but no retinal lesions. The left eye had hypopyon in the anterior chamber with numerous aqueous cells, and retinal white infiltrates with retinal hemorrhages. The aqueous cells, obtained by anterior chamber paracentesis, were positive for CD3, CD56, and Epstein-Barr virus-encoded RNA, but negative for CD20 by immunocytochemical staining. Head magnetic resonance imaging demonstrated white matter lesions in the anterior to parietal lobes on the right side. The patient underwent intrathecal methotrexate injection and external beam radiation at 40 Gy, covering the entire brain and both eyes. The retinal lesions and hypopyon disappeared. Two months later, the patient died of renal failure, and autopsy demonstrated multi-organ involvement of lymphoma cells. In conclusion, we report a case of NK/T-cell lymphoma relapse with intraocular lesions, after combined chemotherapy and hematopoietic stem cell transplantation.

Central nervous system prophylaxis in diffuse large B-cell lymphoma

Central nervous system (CNS) involvement with diffuse large B-cell lymphoma (DLBCL) is a relatively uncommon manifestation; with most cases of CNS involvement occuring during relapse after primary therapy. CNS dissemination typically occurs early in the disease course and is most likely present subclinically at the time of diagnosis in many patients who later relapse in the CNS. CNS relapse in these patients is associated with poor outcomes. Based on a CNS relapse rate of 5% in DLBCL and weighing the benefits against the toxicities, universal application of CNS prophylaxis is not justified. The introduction of rituximab has significantly reduced the incidence of CNS relapse in DLBCL. Different studies have employed other agents for CNS prophylaxis, such as intrathecal chemotherapy and high-dose systemic agents with sufficient CNS penetration. If CNS prophylaxis is to be given, it should be preferably administered during primary chemotherapy. However, there is no strong evidence that supports any single approach for CNS prophylaxis. In this review, we outline different strategies of administering CNS prophylaxis in DLBCL patients reported in literature and discuss their advantages and drawbacks.

Central nervous system involvement in T-cell lymphoma: A single center experience

Background We characterized the incidence of central nervous system (CNS) involvement, risk factors and outcome in a large single institution dataset of peripheral T-cell lymphoma (PTCL). Methods Retrospective review of the PTCL database at Memorial Sloan Kettering Cancer Center. We identified 231 patients with any subtype of PTCL between 1994-2011 with a minimum six months of follow-up or an event defined as relapse or death. Results Histologies included peripheral T-cell lymphoma-not otherwise specified (PTCL-NOS) (31.6%), angioimmunoblastic (16.9%), anaplastic large cell lymphoma (ALCL), ALK- (12.1%), ALCL, ALK + (6.1%), extranodal NK/T-cell lymphoma (7.4%), adult T-cell leukemia/lymphoma (ATLL) (7.4%), and transformed mycosis fungoides (8.7%). Seventeen patients had CNS disease (7%). Fifteen had CNS involvement with PTCL and two had diffuse large B-cell lymphoma and glioblastoma. Median time to CNS involvement was 3.44 months (0.16-103.1). CNS prophylaxis was given to 24 patients (primarily intrathecal methotrexate). Rates of CNS involvement were not different in patients who received prophylaxis. Univariate analysis identified stage III-IV, bone marrow involvement, >1 extranodal site and ATLL as risk factors for CNS disease. On multivariate analysis, >1 extranodal site and international prognostic index (IPI) ≥ 3 were predictive for CNS involvement. The median survival of patients with CNS involvement was 2.63 months (0.10-75). Conclusions Despite high relapse rates, PTCL, except ATLL, carries a low risk of CNS involvement. Prognosis with CNS involvement is poor and risk factors include: >1 extra nodal site and IPI ≥3.

Current trends in the treatment of primary mediastinal large B-cell lymphoma - an overview

Primary mediastinal large B-cell lymphoma has been recognised as a distinct entity with unique clinical, pathologic, and genetic features. According to WHO 2008 classification it is marked as a variant of diffuse large B-cell lymphoma but shares characteristics with classic Hodgkin lymphoma. Genetic analysis has shown that amplification of the 9p24.1 region is the disease's specific structural alteration. Aggressive behaviour and a tendency to invade surrounding tissues of the thoracic cavity, often causing superior vena cava syndrome, or pleural or pericardial effusions, are the clinical hallmarks of this disease. For a long period of time it has been considered as a disease with poor prognosis, which responds poorly to the conventional treatment created for diffuse large B-cell lymphoma. An elective treatment has not yet been established, but recently the situation has became much more favourable. After the introduction of rituximab the cure rates have risen to over 80%, and the most recent results have demonstrated a new insight with dose-adjusted intensified continuous treatments, in which the cure rates have exceeded 90%. Current trends have led to the introduction of dose-adjusted intensified protocols becoming a standard of care, whereas the use of radiotherapy remains controversial because of the questionable predictive value of post-treatment PET/CT validity. The relapse rate is very low after two years of sustained complete remission. If the disease relapses or is resistant the outcome is very poor regardless of the applied treatment modality.

Prediction of Central Nervous System Relapse of Diffuse Large B-Cell Lymphoma Using Pretherapeutic [18F]2-Fluoro-2-Deoxyglucose (FDG) Positron Emission Tomography/Computed Tomography

Central nervous system (CNS) relapse of diffuse large B-cell lymphoma (DLBCL) is a rare complication, but has a poor prognosis with unknown pathophysiology. Recent trials of CNS prophylaxis have shown to be ineffective, despite patient's selection using several known clinical risk factors. In this study, the authors evaluated the value of pretreatment [F]2-Fluoro-2-deoxyglucose positron emission tomography in predicting CNS relapse in DLBCL patients.The authors analyzed 180 pathologically confirmed DLBCL patients, retrospectively. Patients underwent [F]2-Fluoro-2-deoxyglucose positron emission tomography/computed tomography before first line rituximab to cyclophosphamide, doxorubicin, vincristine, and prednisone therapy. Clinical characteristics were evaluated and total lesion glycolysis (TLG) with a threshold margin of 50% was calculated.Among age, sex, Ann Arbor stage, International Prognostic Index, revised International Prognostic Index, high serum lactate dehydrogenase level, presence of B symptoms, bulky disease (≥10 cm), extranodal lesion involvement, bone marrow involvement, high metabolic tumor volume ( >450 mL), and high TLG50 (>2000), the high TLG50 was the only significant prognostic factor for predicting CNS relapse in a multivariate analysis (P = 0.04). Kaplan-Meir survival analysis between high TLG50 (>2000) and low TLG50 (≤2000) groups revealed significantly different mean progression free survival (PFS) of 1317.2 ± 134.3 days and 1968.6 ± 18.3 days, respectively (P < 0.001).High TLG50 on [F]2-Fluoro-2-deoxyglucose positron emission tomography/computed tomography is the most significant predictor of CNS relapse in un-treated DLBCL patients.

Influence of Rituximab on Central Nervous System Relapse in Diffuse Large B-Cell Lymphoma and Role of Prophylaxis--A Systematic Review of Prospective Studies

Despite the improvement in overall survival in patients with diffuse large B-cell lymphoma (DLBCL) in the rituximab era, the occurrence of central nervous system (CNS) relapse heralds a very poor prognosis. The evidence is conflicting on the incidence and pattern of CNS relapse in the rituximab era compared with before the rituximab era and on the role of CNS prophylaxis. We conducted a systematic analysis of the data from 7 prospective studies, studying the incidence and type of CNS relapse, the role of prophylaxis, and survival after CNS relapse, with and without rituximab-based chemotherapy. No statistically significant difference was found in the incidence of CNS relapse with the use of rituximab-based chemotherapy compared with CHOP (cyclophosphamide, doxorubicin, vincristine [Oncovin], prednisone) chemotherapy. Leptomeningeal disease was more common and the survival after CNS disease was better in the rituximab era. No difference was found in the incidence of isolated CNS relapse. Chemoprophylaxis significantly decreased the incidence of CNS recurrence. The use of rituximab has not influenced the incidence of CNS relapse compared with the use of CHOP. Chemoprophylaxis plays a significant role in high-risk patients with DLBCL in decreasing CNS recurrence. Large randomized clinical trials are warranted to differentiate between intrathecal and systemic chemoprophylaxis.