Female patient, 72 years old, diagnosed with cerebral infarction and residual hemiparesis, admitted for a worsening of motor deficits and dysarthria. The computed tomography of the skull revealed complex images suggestive of brain metastases. No primary site of origin was demonstrated in the tests performed. The patient died from acute respiratory failure. In the necropsy, it was determined a pulmonary thromboembolism and primary cerebral lymphoma as the causes of death. The low incidence of this tumor, its presentation with multiple lesions in 25 to 50% of patients and its morphologically heterogeneous aspect motivated a discussion at the clinicopathologic session. The debate was focus in setting the cronopathogram of the disease. A study of the autopsy and a review of the condition are presented as a way to get experiences in order to extend life in other patients, by sharing this fatal case, which is the fundamental objective of post-mortem studies.