Multiple, primary brain tumors with diverse origins and different localizations: Case series and review of the literature

Background: Multiple, primary brain tumors with different histological types occurring in the same patient are extremely rare. Several hypotheses have been proposed, and the pathophysiology of coexisting tumors has long been debated; however, due to low incidence, standard practices for this scenario are still inconclusive. Case Description: The authors describe 6 cases of coexisting tumors. By conducting a literature research focused on the computed tomography (CT) era and patients without prior radiation or phakomatosis. Sixty-five such reported cases were identified. In addition, the authors summarize their experience in 6 patients including histopathological features, chronological presentations, outcomes, mortality, and management from their series as well as from previous cases from the reported literature. Conclusion: The coexistence of multiple, primary brain tumors is an interesting condition. Surgical management remains the major treatment; malignant histology has a poor prognostic factor.