Clinical Pearls & Morning Reports
In any patient who has pathologically enlarged lymph nodes and systemic symptoms, lymphoma and Castleman’s disease should be ruled out. Read the Case Study of the Massachusetts General Hospital.
Q. Describe some of the features of angioimmunoblastic T-cell lymphoma.
A. Angioimmunoblastic T-cell lymphoma is the second most common peripheral T-cell lymphoma. This disease arises from the peripheral helper T cell that aberrantly expresses the cell-surface marker CD10 and is associated with plasmacytosis and polyclonal hypergammaglobulinemia. Constitutional B symptoms, diffuse lymphadenopathy, and autoimmune manifestations are common features. The median age at disease onset is 65 years.
Q.What inflammatory condition can mimic angioimmunoblastic T-cell lymphoma?
A. Multicentric Castleman’s disease can be difficult to distinguish from angioimmunoblastic T-cell lymphoma on clinical grounds.
A: Infectious mononucleosis is the clinical syndrome associated with acute EBV infection. EBV infection typically occurs during one of two distinct time periods; the first wave of infection occurs during early childhood, before the age of 5 years, and the second wave occurs during the second and third decades of life. Most adults have been infected with EBV, and only 3 to 10% of adults older than 40 years of age have not been infected. As compared with children and young adults, older patients with primary EBV infection are less likely to present with pharyngitis and are more likely to have severe illness that necessitates hospitalization. Primary EBV infection is characterized by abnormal results on flow cytometry of the peripheral blood, including an inverted CD4:CD8 ratio and frequent down-regulation of certain pan–T-cell antigens. The presence of an expanded CD8+ T-cell population corresponds to the presence of atypical-appearing lymphocytes on peripheral-blood smears. Biopsy specimens of affected lymph nodes and tonsils show a number of morphologic features that mimic the features of lymphoma, including architectural distortion, an immunoblastic proliferation with cytologic atypia, and necrosis.
A: Several subtypes of aggressive lymphoma are associated with EBV infection, including Burkitt’s lymphoma, diffuse large B-cell lymphoma, lymphomatoid granulomatosis, and angioimmunoblastic T-cell lymphoma. However, these cancers are associated with latent, chronic EBV infection and not with acute EBV mononucleosis. In a patient with EBV viremia and diffuse lymphadenopathy that is worrisome for lymphoma, it is critical to perform viral serologic tests to rule out primary infection.