Lymphoma of the central nervous system originating from the septum pellucidum region: Two case reports with literature review.

RATIONALE: Non-Hodgkin lymphoma affecting the brain, eyes, and cerebrospinal fluid without systemic spread is known as primary central nervous system lymphoma (PCNSL). While intracerebroventricular PCNSL is commonly found in the lateral ventricles and the third and fourth ventricles, the occurrence of PCNSL originating from the septum pellucidum is extremely rare. PATIENT CONCERNS: Two patients presented with recent memory loss and high cranial pressure. DIAGNOSES: Magnetic resonance imaging revealed a clear enhancing lesion in the septum pellucidum region. Pathological examination confirmed that both cases were primary large B-cell lymphoma GCB (germinal center B-cell-like) subtypes located in an "immune-privileged" area. INTERVENTIONS: Both patients underwent total tumor resection, and the procedures were successfully completed without surgical complications. OUTCOMES: Over a 1-year period, treatment included four cycles of high-dose methotrexate combined with temozolomide. During the follow-up period (19-23 months), no recurrence of the lymphoma was observed. LESSONS: In cases of PCNSL in the septum pellucidum, it is crucial to consider it as a potential differential diagnosis for intraventricular tumors. Surgical interventions should focus on maximizing tumor resection while ensuring the protection of critical structures like the fornix and peripheral neural components. The role of surgery compared to biopsy, as well as the long-term complications, necessitates extended follow-up. Additionally, an individualized treatment approach, considering factors such as age, Karnofsky performance score, and organ function assessment, can lead to positive outcomes.

Metformin protects fibroblasts from patients with GNE myopathy by restoring autophagic flux via an AMPK/mTOR-independent pathway.

UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) myopathy is an autosomal recessive disease characterized by rimmed vacuoles (RVs). Previous studies have shown that metformin protects against several neuromuscular disorders. In the present study, we summarize the clinical features of three GNE patients with the p.D207V mutation. The pathogenesis of GNE myopathy is described, and the significance of metformin in this disease is observed. Skin biopsy-derived fibroblasts from patients with GNE myopathy, carrying a D207V mutation in GNE, were cultured. GNE fibroblasts and control fibroblasts were treated under normal culture conditions, serum starvation conditions, or serum starvation + metformin conditions. Histopathological and immunohistochemical analyses of muscle samples showed that autophagy was involved in the formation of RVs in the muscle of patients. Starved GNE fibroblasts showed decreased autophagy-related proteins and impaired autophagic flow (p < 0.05). The mRFP-GFP-LC3 assay showed that the fusion of autophagosomes with lysosomes was partially blocked in GNE cells. Notably, metformin treatment upregulated the expression of autophagy proteins, increased the number of autolysosomes (p < 0.001), and influenced the viability of GNE cells (p < 0.001). Furthermore, adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) and phosphorylated (p)-AMPK expression levels were upregulated in serum-starved GNE fibroblasts, while the mammalian target of rapamycin (mTOR) and p-mTOR expression levels were downregulated in both groups. Metformin treatment inhibited the AMPK-mTOR signaling pathway. Our results suggest that metformin plays a protective role in the GNE fibroblast by restoring autophagic flux and through the AMPK/mTOR-independent pathway.

Lymphomatoid granulomatosis with the central nervous system involvement as the main manifestation: a case report.

BACKGROUND: Lymphomatoid granulomatosis (LyG) is a rare extralymphatic lymphoproliferative disease characterized by lymphocytic invasion into vascular walls and damage to blood vessels. The lungs are affected in 90% of LyG cases, followed by the skin, central nervous system (CNS), kidneys and liver. CASE PRESENTATION: Here we report a case of a young woman with LyG, with CNS involvement as the initial clinical manifestation. Computer tomography (CT) scans showed multiple nodular, patchy and flocculent high-density shadows in both lungs without mediastinal lymph node enlargement. Magnetic resonance imaging (MRI) scans showed multiple abnormal signal intensities in the right cerebellar hemisphere, frontal, parietal and temporal lobes, and dorsal brainstem, which became patchy and annular after enhancement. The post-operative pathological analysis of lesion samples confirmed the diagnosis of grade II LyG. CONCLUSIONS: LyG should be concerned in young adults showing multiple radiological brain and lung lesions. Resection and postoperative medication of steroid hormones and IFN-α may be effective in the treatment of LyG.