<unk>  (FA-DLBCL) is an extremely rare form of the diffuse large B-cell<unk> s (DLBCL). DLBCL are<unk> s in which a particular type of lymphocyte, the B-cell, proliferates excessively, invades multiple tissues, and often causes life-threatening tissue damage. DLBCL have various forms as exemplified by one of its subtypes, diffuse large B-cell<unk> <unk>  with chronic inflammation (DLBCL-CI). DLBCL-CI is an aggressive malignancy that develops in sites of chronic inflammation that are walled off from the immune system. In this protected environment, the B-cells proliferate excessively, acquire malignant gene changes, form tumor masses, and often spread outside of the protected environment. In 2016, the World Health Organization provisionally classified FA-DLBCL as a DLBCL-CI. Similar to DLBCL-CI, FA-DLBCL involves the proliferation of EBV-infected large B-cells in restricted anatomical spaces that afford protection from an individual's immune system. However, FA-DLBCL differs from DLBCL-CI in many other ways, including, most importantly, its comparatively benign nature. Some researchers have suggested that this disease should be regarded as a non-malignant or pre-malignant lymphoproliferative disorder rather than a malignant DLBCL-CI. FA-DLBCL is an Epstein–Barr virus-associated lymphoproliferative disease (EBV+ LPD), i.e. disease in which lymphocytes infected with the Epstein-Barr virus (EBV) proliferate excessively in one or more tissues. EBV infects ~95% of the world's population to cause no symptoms, minor non-specific symptoms, or infectious mononucleosis. The virus then enters a latency phase in which the infected individual becomes a lifetime asymptomatic carrier of the virus. Some weeks, months, years, or decades thereafter, a very small fraction of these carriers develop any one of various EBV-associated benign or malignant diseases. In FA-DLBCL as well as DLBCL-CI, EBV infects B-cells to promote their proliferation and thereby the development of either disease. FA-DLBCL most commonly develops within immunologically sequestered sites such as body cavities (e.g. pseudocysts) and foreign bodies (e.g. artificial heart valves) where<unk> , a breakdown product of the blood clotting factor,<unk> ogen, has deposited. It is almost always discovered as an incidental finding in specimens taken from these sites when they are examined for reasons not directly related to the FA-DLBCL infiltrates. As reviewed in a publication of 2019, the disorder has been diagnoses in 47 individuals who are predominantly elderly males; it is almost uniformly amenable to various treatments and takes a benign course. However, the disease, when occurring within vascular or cardiac sites, does have a risk of being complicated by the development of embolisms due to the dislodgement of blood clots that travel through the vascular system to cause, e.g. strokes.
Fibrin-associated diffuse large B-cell lymphoma
Nodal marginal zone B cell lymphoma
Marginal zone B-cell lymphoma
Pediatric-type follicular lymphoma
Diffuse large B-cell lymphoma
Splenic marginal zone lymphoma
Chronic multifocal Langerhans cell histiocytosis
Epstein–Barr virus positive diffuse large B-cell lymphoma, not otherwise specified