The value of diagnostic vitrectomy: Histocytopathology techniques for the diagnosis of lymphoma of the retina

Primary large B-cell lymphoma of the retina, vitreous, and central nervous system (CNS), is an intraocular tumor with an unspecific and insidious clinical presentation. Pars plana vitrectomy (PPV) and optical coherence tomography (OCT) are useful diagnostic tools for this malignant process. The aim of this study is to evaluate the diagnostic efficacy of PPV for these intraocular lesions under a modified diagnostic protocol with a clinical pathological correlation with OCT imaging. A total of 115 samples were collected after a vitrectomy procedure (aspiration or vitrectomy cassette). The samples were centrifuged, and the precipitates were collected. A cell block was prepared and analyzed with multiple stains and an immunohistochemistry (IHC) panel, including B- and T-cell markers, as well as light chain markers, to establish the monoclonal nature of the tumor. Of the 115 samples, 9 (7.83%) were diagnosed with large B-cell lymphoma of the retina, vitreous, and CNS. Diagnostic vitrectomies for the large B-cell lymphoma of the retina, vitreous, and CNS is an excellent tool for the diagnosis of this entity. A negative diagnostic PPV with a strong suspicious OCT image, where the neoplastic cells are located between the retinal pigmented epithelium and Bruch’s membrane, the latter procedure should be either repeated or a chorioretinal biopsy be performed. In contrast, a positive vitrectomy using the IHC panel for large B-cell lymphoma of the retina, vitreous, and CNS is pathognomonic of this condition. In addition, the OCT is an important tool to help in the diagnosis of this difficult entity. The diagnostic PPV provided suitable vitreous samples to all patients with undetermined uveitis and/or intraocular tumor suspicion. A morphological and immunohistichemical (IHC) analysis enabled a conclusive diagnosis of retina, vitreous and CNS lymphoma in all patients submitted to the procedure.