1. Frozen Section/Touch Prep
Brain Biopsy
Frozen Section/Touch Prep

2. Brain Biopsy for Suspected Neoplasm
Is it Abnormal?
Is it Neoplastic?
What Type of Neoplasm is it?
What is the Neoplasm’s Grade?

6. Brain Biopsy for Suspected Neoplasm
Is it Abnormal? Yes
Is it Neoplastic? Yes
What Type of Neoplasm is it?
What is the Neoplasm’s Grade?

7. TOUCH PREP-GLIOBLASTOMA MULTIFORME

8. TOUCH PREP-CNS LYMPHOMA

9. TOUCH PREP-PRESENT CASE

10. TOUCH PREP-PRESENT CASE

14. H&E
CD20
EBER
Ki67

15. Diagnosis: Malignant Lymphoma, High Grade, Diffuse Large B Cell Type,
EBV positive

16. CNS Lymphomas Primary CNS Lymphoma Secondary CNS Lymphoma
Immunosuppressed Patients
Immunocompetent Patients
Secondary CNS Lymphoma
10% of systemic non-Hodgkin’s lymphomas involve CNS
Leptomeninges, epidural space are favored locations

17. Primary CNS Lymphoma Immunosuppressed Host Immunocompetent Host
AIDS, s/p transplant, inherited immunodeficiency
95% EBV positive
Median survival=1 year
Immunocompetent Host
Usually >60 years old
10% EBV positive
Median survival=3 years

18. Primary CNS Lymphoma Epidemiology
Incidence increased 10X worldwide due to AIDS
Clinical
10% of patients have a history of another cancer
Respond dramatically to corticosteroids
“ghost tumor”, “sentinel lesion”
Radiology
Often homogeneously enhancing, periventricular
Pathology
Most Diffuse Large B Cell Lymphoma
Hodgkins lymphoma=rare
Treatment
Gross total resection not indicated
Biopsy for diagnosis followed by chemotherapy

19. Quandary There are no B lymphocytes normally in the CNS
How do you get Primary B cell lymphomas in CNS?

20. Primary CNS Lymphoma: Possible Etiologies
B cell transformed elsewhere in body that develops adhesion molecules specific for CNS endothelium
Systemic lymphoma that is eradicated by immune system but is protected in CNS
Clonal B cell neoplasm arising in polyclonal intracerebral inflammatory response

21. Argani’s rule of tumor pathology
Stuff happens