NCIt definition : An indolent, low-grade B-cell non-Hodgkin lymphoma that arises from the choroid, iris,
or ciliary body. It is characterized by the presence of a diffuse infiltrate of small,
round lymphocytes. Lymphoid follicles with germinal centers may be present. In the
past these tumors were termed 'reactive lymphoid hyperplasia'. Now they are considered
low-grade B-cell lymphomas, most commonly extranodal marginal zone lymphomas of mucosa-associated
lymphoid tissue.;