Secondary CNS lymphoma
Secondary CNS lymphoma (SCNSL) refers to central nervous system spread of a lymphoma that originated elsewhere (in contrast to Primary CNS lymphoma). It is typically a non-Hodgkin lymphoma, and may be an isolated recurrence or may be part of a systemic disease at the time of presentation 2. Unlike primary CNS lymphoma it more commonly involves the leptomeninges and is uncommonly detectable on CT/MR, with malignant cells found on CSF aspiration.
Leptomeningeal lymphoma accounts for two thirds of cases of secondary CNS lymphomas, the remaining third presenting like primary CNS lymphomas (parenchymal disease).
The histologic grade of the primary lymphoma influences the risk of developing SCNSL: if the primary lymphoma is classified as indolent, aggressive, or highly aggressive, there is a 3%, 9%, and 27% risk, respectively, of developing SCNSL 2.
SCNSL can manifest with a new-onset headache, cranial nerves palsies (especially the III, IV, VI, and VII), changes in mental status, and even coma and seizures 2.
SCNSL can be divided in those with leptomeningeal involvement, the most common form, those with a parenchymal involvement, or as a combination of the two 2.
Risk factors for a SCNSL are 2:
- the variant of primary lymphoma
- involvement of more than one extranodal site
- serum lactate dehydrogenase level greater than three times the normal limit
- advanced stage of the systemic disease
- high international prognostic index
Contrast enhanced MRI is the modality of choice. Imaging features of leptomeningeal secondary CNS lymphoma include leptomeningeal, dural, subependymal and cranial nerve enhancement. Communicating hydrocephalus may be present.
Parenchymal SCNSL appears quite similar to primary CNS lymphoma, however it can be accompanied by leptomeningeal and subependymal enhancement.
- 1. Haldorsen IS, Espeland A, Larsson EM. Central nervous system lymphoma: characteristic findings on traditional and advanced imaging. AJNR Am J Neuroradiol. 2011;32 (6): 984-92. AJNR Am J Neuroradiol (full text) - doi:10.3174/ajnr.A2171 - Pubmed citation
- 2. DeRosa P, Cappuzzo JM, Sherman JH. Isolated recurrence of secondary CNS lymphoma: case report and literature review. J Neurol Surg Rep. 2014;75 (01): e154-9. doi:10.1055/s-0034-1378152 - Free text at pubmed - Pubmed citation
- overview of lymphoma
WHO classification of tumours of haematopoietic and lymphoid tissues
- Hodgkin lymphoma
- mature B-cell lymphoma
- mature T-cell and NK-cell lymphoma
- post-transplant lymphoproliferative/lymphoproliferation disorders
- location-specific lymphomas
- central nervous system
- head and neck lymphoma
- thoracic lymphoma
- gastrointestinal lymphoma
- hepatobiliary lymphoma
- genitourinary lymphoma
- musculoskeletal lymphoma
- cutaneous lymphoma
- lymphoma staging