Axial FLAIR MRI. Lymphomatous involvement of the corpus callosum. Primary CNS lymphoma invades areas that are in contact with the ventricles or meninges (in this case the corpus callosum).
CNS Lymphoma
Primary CNS lymphoma
- Accounts for <5% of brain tumors.
- Invades the brain parenchyma, especially the periventricular regions and superficial brain regions (areas that are in contact with the cerebral ventricles or meninges) and is typically contrast enhancing on imaging.
- Common clinical presentations: encephalopathy/lethargy, headache, focal neurological deficits.
- AIDS is an important risk factor for Primary CNS lymphoma.
- If the patient has both CNS lymphoma and HIV, then Epstein-Barr virus (EBV) will be detectable in the tumor, itself, and in the CSF. These are typically B cell lymphomas. It's believed that the lymphoma results from EBV transformation of activated B cells in the setting of poor T cell defense against the EBV-infected B cells.
- EBV is NEGATIVE in the vast majority (>90%) of immunocompetent patients.
- Histopathology demonstrates diffusely infiltrative atypical (large) lymphocytes in an angiocentric (perivascular) pattern. The cells have prominent nucleoli, frequent mitoses, and scant cytoplasm.
- Radiographically demonstrate enhancing (often intensely) lesions that are more commonly single (less commonly multiple) and are periventricular in location.
- Note that lymphoma responds dramatically to steroids, so it can help with tumor mass but should be avoided PRIOR to biopsy.
- Highly aggressive tumor with poor prognosis: typically < 1 year (often, just several months); 5-year survivial rate: 25 - 45%.
- Immunocompromised hosts have a worse prognosis.
- Treatment:
- Radiation
- Chemotherapy: cytosine, arabinoside, intrathecal methotrexate
- If HIV +, anti-retroviral therapy key to therapy
- Note that CNS lymphoma is almost never indicated because of the deep white matter (typically, periventricular) location of the tumor.
Secondary CNS Lymphoma
- Occurs from CNS invasion of systemic lymphoma
- Accordingly, it more commonly invades the leptomeninges (~2/3 of the time) and only invades the brain parenchyma 1/3 of the time.
- In addition to the leptomeninges, secondary CNS lymphoma infiltrates subependymal regions, accumulates along dura mater, and encases the cranial nerves.
Neuromuscle complications of systemic lymphoma
- Non-Hodgkin lymphoma is associated with inflammatory myopathies: more commonly with dermatomyositis but also with polymyositis.
References
- Adesina, Adekunle M., Tarik Tihan, Christine E. Fuller, and Tina Young Poussaint. Atlas of Pediatric Brain Tumors. Springer, 2016.
- Aki, Hilal, Didem Uzunaslan, Caner Saygin, Sebnem Batur, Nukhet Tuzuner, Ali Kafadar, Seniz Ongoren, and Buge Oz. “Primary Central Nervous System Lymphoma in Immunocompetent Individuals: A Single Center Experience.” International Journal of Clinical and Experimental Pathology 6, no. 6 (May 15, 2013): 1068–75.
- Gray, Frangoise, Charles Duyckaerts, and Umberto De Girolami. Escourolle and Poirier’s Manual of Basic Neuropathology. OUP USA, 2013.
- Haldorsen, et. al. Central Nervous System Lymphoma: Characteristic Findings on Traditional and Advanced Imaging. American Journal of Neuroradiology. 2010.
- Mansour, et. al. MR imaging features of intracranial primary CNS lymphoma in immune competent patients. Cancer Imaging201414:22
- Newton, Herbert B. Handbook of Brain Tumor Chemotherapy, Molecular Therapeutics, and Immunotherapy. Academic Press, 2018.
- Perry, Arie. “WHO’s Arrived in 2016! An Updated Weather Forecast for Integrated Brain Tumor Diagnosis.” Brain Tumor Pathology 33, no. 3 (July 1, 2016): 157–60. https://doi.org/10.1007/s10014-016-0266-4.
- Prayson, Richard A., and Mark L. Cohen. Practical Differential Diagnosis in Surgical Neuropathology. Springer Science & Business Media, 2000.
Image Reference
- Histopathological Slide
- Histopathologic Image of CNS B-Cell Lymphoma. Stereotactic Biopsy. H & E Stain. January 20, 2006. No machine-readable source provided. Own work assumed (based on copyright claims). KGH assumed. https://commons.wikimedia.org/wiki/File:CNS_lymphoma_(1)_B-cell_type.jpg.