Brain Biopsy

Frozen Section/Touch Prep

Brain Biopsy for Suspected Neoplasm

• Is it Abnormal?

• Is it Neoplastic?

• What Type of Neoplasm is it?

• What is the Neoplasm’s Grade?

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?

TOUCH PREP-GLIOBLASTOMA MULTIFORME

TOUCH PREP-CNS LYMPHOMA

TOUCH PREP-PRESENT CASE

TOUCH PREP-PRESENT CASE

H&E

EBER

CD20

Ki67

Diagnosis:

Malignant Lymphoma, High Grade,

Diffuse Large B Cell Type,

EBV positive

CNS Lymphomas

• Primary CNS Lymphoma– Immunosuppressed Patients– Immunocompetent Patients

• Secondary CNS Lymphoma– 10% of systemic non-Hodgkin’s lymphomas

involve CNS– Leptomeninges, epidural space are favored

locations

Primary CNS Lymphoma

• Immunosuppressed 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

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

Quandary

• There are no B lymphocytes normally in the CNS

• How do you get Primary B cell lymphomas in CNS?

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

Argani’s rule of tumor pathology

Stuff happens