Intravascular Large B-Cell Lymphoma.

Context.—: Intravascular large B-cell lymphoma (IVLBCL) is a rare hematopathologic entity, posing both a clinical and histologic challenge for diagnosis. Numerous pitfalls can hinder making the diagnosis.

Objective.—: To summarize recent developments in literature pertaining to IVLBCL and point out key pitfalls pathologists should be prepared to encounter.

Data Sources.—: Literature review via PubMed search and hospital (Darnall Medical Library) resources.

Conclusions.—: The 3 primary pitfalls of IVLBCL include masking of IVLBCL, mimicry by IVLBCL, and mimicry of IVLBCL. These scenarios illustrate the importance of histologic pattern recognition and subsequent usage of immunohistochemistry, especially in context of a clinical history that may be noncharacteristic.