Rare central nervous system lymphomas

Primary Diffuse Large B-Cell Lymphoma of the Central Nervous System-Outcomes in Finland: A Nationwide Population-Based Study

Primary central nervous system lymphoma (PCNSL) is a rare and aggressive malignancy commonly presenting with a rapid disease course and poor prognosis. Recent clinical trials have indicated improved treatment outcomes in a highly selected patient population. However, real-world data focusing on long-term, population-based outcomes remain largely unexplored. We analyzed trends in relative survival (RS) in patients diagnosed with PCNSL in Finland from 1995 to 2018. We identified 718 PCNSL patients from the comprehensive Finnish Cancer Registry (FCR) (51% males, median age 67.8 years). For the entire cohort, 5-year overall survival (OS) and RS rates were 21% and 22%, respectively. The 2-year RS was 39% for patients younger than 75 years and 14% for older patients. A gradual increase in the 2-year RS rate was observed over successive chronological diagnostic periods. Age above 75 years at diagnosis (HR 3.65, 95% CI: 2.73-4.89) and diagnosis during a calendar period of 1995-2006 (HR 1.30, 95% CI: 1.10-1.53) were associated with a significantly increased risk of death. An increase in the number of patients diagnosed with PCNSL during the study period was confirmed, and the prognosis of patients diagnosed after the age of 75 years continues to be dismal.

Correlation between immune microenvironment and clinicopathological characteristics and prognosis of primary large B-cell lymphoma of immune-privileged sites

OBJECTIVES

To explore the correlation between tumor-associated macrophages (TAMs), tumor-infiltrating lymphocytes (TILs), and tumor-associated angiogenesis (TAA) in the tumor microenvironment with the clinicopathological characteristics and prognosis of primary large B-cell lymphoma of immune-privileged sites (LBCL-IP).

METHODS

A total of 46 cases of LBCL-IP from the Department of Pathology, the Third Affiliated Hospital of Xinjiang Medical University, from January 2010 to February 2024, were collected, along with clinical and follow-up data of LBCL-IP patients. Immunohistochemistry and triple immunofluorescence were used to detect related proteins of TAMs, TILs, and TAA, and to analyze the correlation between TAMs, TILs, TAA, and the polarization of TAMs with the clinical and prognostic factors of LBCL-IP patients.

RESULTS

There are 30 cases (65.2 %) showed high expression of CD68 proteins, 32 cases (69.6 %) showed high expression of CD163 proteins, 19 cases (41.3 %) showed high expression of CD4 proteins, 34 cases (73.9 %) showed high expression of CD8 proteins, and 25 cases (54.3 %) showed high expression of CD34 proteins. A total of 28 cases (60.9 %) showed CD68+CD163+/CD68+CD86+≥1. The chi-square tests showed that high expression of CD163 proteins was positively correlated with elevated LDH and BMG values, and the count of CD68+CD163+/CD68+CD86+≥1 was positively correlated with ECOG scores ≥2, Ann Arbor staging III-IV, and increased BMG value. High expression of CD8 proteins was positively correlated with a Ki-67 proliferation index ≥70 %, and high MVD values were positively correlated with Ann Arbor staging III-IV. The Kaplan-Meier estimator analysis showed that LBCL-IP patients with low expression of CD68 proteins, high expression of CD163 proteins, CD68+CD163+/CD68+CD86+≥1, low expression of CD8 proteins, high MVD values, ECOG scores ≥2, Ann Arbor staging III-IV, LDH ≥250 U/L, BMG ≥2.2 mg/L, and IPI scores ≥2 had shorter survival times. Multivariate Cox regression analysis showed that low expression of CD8 proteins, CD68+CD163+/CD68+CD86+≥1, LDH ≥250 U/L, and ECOG scores ≥2 are independent risk factors affecting the survival of LBCL-IP patients.

CONCLUSION

M2-polarized TAMs and low infiltration of CD8+ TILs were more strongly correlated with poor clinical pathological indicators and worse prognosis, and MVD values may serve as an aiding means for the diagnosis and prognostic prediction of LBCL-IP disease.

Advances in Primary Central Nervous System Lymphoma

PURPOSE OF REVIEW

Optimal initial management can have a significant impact in long-term outcome in primary CNS lymphoma. This article reviews recent advances and the state of the field.

RECENT FINDINGS

Genomic analysis of CSF cell-free DNA has emerged as a new diagnostic tool for PCNSL. Treatment options have likewise evolved, with mature data from first-line chemotherapy-based prospective trials disclosing excellent results in younger (< 60-65) patients, with a cure achieved in a majority. However, results in older patients remain dismal, with several new salvage options under investigation including BTK pathway-targeted therapies, and CAR-T cell treatments. Meanwhile, low-dose radiation has emerged as an additional alternative for consolidation therapy. For younger PCNSL patients, the goal of treatment is now a cure, with the next frontier being the development of therapies affording optimized neurocognitive outcome and lower toxicity. Treatment for older patients remains however an unmet need, with several promising clinical trials ongoing.

Posterior fossa Hodgkin's lymphoma radiographically mimicking an arteriovenous malformation: illustrative case

BACKGROUND

Intracranial Hodgkin's lymphoma (HL) is an exceedingly rare condition that is at an increased risk of misdiagnosis and mismanagement, especially when initial radiographic evidence points to an alternative pathology.

OBSERVATIONS

The authors describe the case of a 75-year-old female who presented with a posterior fossa lesion initially concerning for a vascular malformation on computed tomography imaging due to perilesional hypervascularity. Subsequent angiography revealed a developmental venous anomaly (DVA) but no arteriovenous shunting. The patient's clinical history combined with magnetic resonance imaging findings prompted a tissue biopsy, which demonstrated a rare case of central nervous system (CNS) HL. The neoangiogenesis of this CNS HL with an adjacent DVA contributed to the original radiographic misdiagnosis of an arteriovenous malformation. HL's angiogenic potential, coupled with the proangiogenic environment induced around DVAs, may have contributed to this rare CNS HL metastasis to the cerebellum. The potential misdiagnosis of posterior fossa CNS HL has also been seen in several prior cases reviewed herein.

LESSONS

Hypervascular tumors, especially when associated with an adjacent DVA, should also be considered when first evaluating suspected intracranial vascular lesions. Although rare, CNS HL should be included in the differential diagnosis for patients with a prior history of HL. https://thejns.org/doi/10.3171/CASE24238.

Intracranial Involvement of Systemic Hodgkin Lymphoma: A Case Report and Literature Review

A 27-year-old male patient, previously diagnosed with Hodgkin lymphoma (HL), presented with gait disturbance. Brain MRI showed a 4.5 cm mass lesion in the right occipital lobe, suggesting either intracranial involvement of HL or a potential meningioma. Despite high-dose methotrexate and steroid treatment, the patient's symptoms persisted, and imaging showed an enlarging mass, leading to surgical intervention. Histopathological examination confirmed central nervous system (CNS) involvement of HL. Postoperatively, the patient underwent whole-brain radiotherapy and demonstrated marked clinical improvement. Our literature review from 1980 to 2023 identified only 46 cases of intracranial HL (IC-HL), underscoring its rarity. Lymphomas represent 2.2% of brain tumors, with 90%-95% being diffuse large B-cell lymphoma (DLBCL). In contrast, the incidence of CNS-HL patients is a mere 0.02%. Notably, IC-HL and intracranial DLBCL have differences in their typical locations and treatment strategies. Unlike DLBCL, which predominantly appears in the supratentorial region (87%), IC-HL is found there in 61.5% of cases. Additionally, 33.3% of IC-HL cases occur in the cerebellum, with 43.5% associated with posterior circulation regions. Furthermore, while biopsy followed by chemotherapy induction is a common strategy for DLBCL, 81.8% of IC-HL cases underwent surgical resection, and only 18.1% had a biopsy alone. The distinct characteristics of IC-HL tumors, including their larger size, attachment to the dura, and fibrotic nature with clear boundaries, might account for the preference for surgical intervention. The unique features of IC-HL compared to DLBCL highlight the need for distinct considerations in diagnosis and management.