Lymphomas can arise from most any lymphatic tissue (lymph nodes, spleen, thymus, mucosa associated lymphoid tissue (MALT). The eye is a fairly rare place to get lymphoma but it does happen. The medical term for this is an Extranodal Lymphoma as it arises outside the lymph nodes.
Non Hodgkin's lymphoma can start in the eye. It is called ocular lymphoma when it did not start elsewhere including the central nervous system (CNS) (brain etc.) These lymphomas are all quite rare. Isolated ocular lymphoma apparently is increasing in frequency, maybe due to occurrence in some AIDS patients. It represents a difficult extranodal site to treat.
Ocular lymphomas should not be confused with other cancers that can might strike the eye or related tissue or spread to the eye from another location.
The most common presenting ocular symptoms are blurred vision and floaters. Pain and conjunctival hyperemia (engorgement of blood vessels around the eye) are rare. Vision is often decreased. Biomicroscopic exam often shows mild anterior segment inflammation with cells and flare and keratic precipitates. Vitreous cells occurring in sheets are characteristic. Although the disease may begin with one eye, bilateral (both eye) involvement is common after several months.
Doctors may look for Interleukin-10, a growth and differentiation factor for B lymphocytes to determine if the condition is lymphoma instead of another eye condition which may be attracting lymphocytes such as an infection. A recent 2004 study suggests that CDR3 polymorphism analysis is recommended to confirm clonality.
The disease treatment may include external beam radiation, chemotherapy, or both.
Radioimmunotherapy regimens such as Zevalin show promising results in clinical trials for many types of B-cell NHLs.