Coexisting sarcoidosis and occult mantle cell lymphoma.

Sarcoidosis and lymphoma are two separate entities that need to be considered in the differential diagnosis of lymphadenopathy. Rarely these two diseases may coexist, in which case there may arise a diagnostic challenge, especially when the available sample is limited. We report a case of occult mantle cell lymphoma arising in an individual with a long history of sarcoidosis.