[Neuralgia of the trigeminal nerve as first symptom of a primary central nervous system lymphoma of non-Hodgkin's type].

Primary central nervous system lymphoma of non-Hodgkin's type are distinguished from systemic non-Hodgkin's lymphoma because of their different pathobiological behaviour. Predisposing factors are pharmacologically induced immunosuppression and those referring to diseases. We present the case of a patient who was sent to hospital in case of emergency due to pain of one half of the face. The symptoms corresponded essentially to neuralgia of the trigeminal nerve. During course other neurological symptoms showed up. The right diagnoses of a primary central nervous system lymphoma of non-hodgkin's type was finally made post mortem. The case especially reveals the difficulties of diagnosis - including negative and confusing MRI-findings - and the variety of differential diagnosis of this also in not immunosuppressed persons more and more frequent kind of tumor.