[Immunohistochemical and molecular genetic profile of mantle cell lymphoma of the lacrimal gland: a case series of an uncommon tumour of the lacrimal gland].

Background Mantle cell lymphomas (MCL) represent a rare subclass of Non-Hodgkin Lymphoma affecting the lacrimal gland (GL).Aim To extensively describe the immunohistochemical profile of GL-MCL.Material und Methods Single center, retrospective electronic records review of 3 patients with biopsy proven LG-MCL.Results The herein presented case series of three patients comprises a focal case involving solely the lacrimal gland, a symptomatic LG-MCL manifesting as the first sign of a systemic disease as well as a case of LG-MCL presenting as a relapsed systemic lymphoma. The three patients presented positive CD19 and CD20, negative CD10 and CD23. One patient showed an uncommon negativity for CD5. The increased expression of cyclin D1 caused by the classical translocation t(11;14) (q13;q32) in the fluorescence-in-situ-hybridisation were observed in all cases. B-cell-lymphoma-2 protein (BCL-2) and transcription factor SOX-11 (SOX-11) were also overexpressed.Discussion LG-MCL show an immunohistochemical profile corresponding to the classical profile of MCL. Overexpression of molecules for target therapies was found in all cases (CD20 for rituximab, BCL2 for Bruton-kinase-inhibitors and CD19 for CAR-T cell therapy). The removal of the GL can potentially drive to severe complications, even if aimed to confirm diagnosis. Therefore, the choice between GL-biopsy and exstirpation should be carefully evaluated, especially in cases of suspected lymphoma.