Clinical Pearls & Morning Reports
Published March 21, 2018
Persons with HIV infection have a markedly higher risk of lymphoma than nonimmunosuppressed persons, and lymphomas in persons with HIV infection tend to be clinically aggressive. Read the latest NEJM Case Records of the Massachusetts General Hospital here.
Q: What are some of the viruses that can cause parotitis?
A: Viral infections can cause rapidly enlarging parotid masses. The classic viral cause is mumps. Other viruses that can cause parotitis include adenovirus, cytomegalovirus, influenza virus, and parainfluenza virus.
Q: What are typical features of benign lymphoepithelial lesions of the parotid gland in patients with HIV infection?
A: Benign lymphoepithelial lesions of the parotid gland are an important cause of parotid swelling in patients with HIV infection. These lesions are typically indolent, bilateral, and manifested by cysts separated by thick septations on imaging studies.
A: Diffuse large B-cell lymphoma is the most common type of non-Hodgkin’s lymphoma in patients with HIV infection; the second most common type is Burkitt’s lymphoma. Rates of lymphoma among patients with HIV infection are highest during the first 6 months after the initiation of antiretroviral therapy (ART), especially among those with low CD4+ T-cell counts. In addition, there have been reports of lymphoma being unmasked within weeks after the initiation of ART, a phenomenon termed “lymphoma immune reconstitution inflammatory syndrome (IRIS).” An important consideration in treating persons with HIV infection and lymphoma is the potential for interactions between antineoplastic agents and antiretroviral medications and overlapping toxic effects. The availability of medications that are associated with low rates of toxic effects and drug interactions supports the continuation of ART during chemotherapy.
A: Before the advent of effective ART, the incidence of non-Hodgkin’s lymphoma in persons with HIV infection was markedly higher than the incidence in the general population. Now that effective ART is available, there has been a substantial change in the incidence of HIV-associated lymphoma, although this change has not been consistent across different types of lymphoma. In a 2014 study, the standardized incidence ratio for non-Hodgkin’s lymphoma in persons with HIV as compared with the general U.S. population was 11.5. However, although rates of diffuse large B-cell lymphoma and primary central nervous system lymphoma have steeply declined over time, the standardized incidence ratio for Burkitt’s lymphoma has not substantially decreased.