Contributed by Mark Fung, MD
Published on line in December 2001
The patient is a forty year old man with enlarged 5 cm right axillary lymph node. No other history is initally given. The following is observed with standard H & E sections, and a limited panel of paraffin section immunohistochemical stains:
Would this likely be a malignant or benign lesion?
These findings are suggestive of a benign lesion. There is acute inflammation, areas of necrosis, monocytoid B-cells. This is a focus of capsular thickening. There is follicle hyperplasia, but otherwise, the T- and B-cells are located in their normal compartments in the the lymph node. There is no evidence of a monoclonality by immunoglobulin light chain expression.
What general categories of benign processes should be in the differential for lymphadenopathy?
Infections: Bacerial, Mycobacterial, Fungal, Viral, Protozoal, Rickettsial, Chlamydial
Local Inflammation: Trauma, Dermatitis
Hypersensitivity Reaction: Serum sickness, Drug reaction (phenytoin)
Autoimmune disorders: Systemic lupus erythematosus, rheumatoid arthritis, dermatomyositis
Endocrine disorders: Hyperthyroidism
Other: Mucocutaneous lymph node syndrome, angioimmunoblastic lymphadenopathy, autoimmune hemolytic anemia
Acid fast, Grocott, and Warthin-Starry stains were performed due to the concern for an infectious etiology. No microorganisms were detected with either the acid fast nor with the Grocott stains. However, the following was noted on the Warthin-Starry stain:
Upon further questioning, the patient admitted to owning a cat.