[Primary Intraocular Lymphoma: Relevance of Diagnostic Vitrectomy].

Primary intraocular lymphomas are rare tumours that can be further subdivided into primary vitreoretinal and the even rarer primary uveal lymphoma. The incidence of primary vitreoretinal lymphoma (PVRL) has increased during the last few decades. Differential diagnostic distinction between lymphoma and posterior uveitis is often difficult, so that adequate diagnosis and treatment is often delayed. This is fatal, because PVRL is often associated with primary central nervous lymphoma. To confirm the diagnosis, prior treatment of cytological or histological detection of lymphoma cells is the gold standard. Therefore, a diagnostic vitrectomy should be performed with vitreous biopsy and sometimes transretinal biopsy. Cytokine analysis, as well as flow cytometry and molecular tests, are only additional methods that can be employed in case enough tumour material is available. After the diagnosis has been made, an interdisciplinary treatment concept must be developed by oncologists and ophthalmologists together.