A case with coincidental diagnosis of primary central nervous system lymphoma and lymph node sarcoidosis.

Primary central nervous system lymphoma (PCNSL) is rare. Clinical and histological differential diagnosis of systemic lymphoma and sarcoidosis continues to be a challenge. The first case report in the German and English literature of PCNSL and synchronous sarcoidosis is presented. Synchronous mediastinal lymphadenopathy suggestive of non-Hodgkin's lymphoma (NHL) or sarcoidosis was noted. Both conditions require alternative therapeutic and prognostic considerations to PCNSL. A regime of intrathecal and adjuvant systemic chemotherapy led to transient clinical improvement prior to the patient's demise through overwhelming sepsis and multiorgan failure. Post mortem findings confirmed synchronous PCNSL with mediastinal lymph node sarcoidosis.