[Relevance of histopathological diagnosis in the treatment of brainstem lesions in adults].

Brainstem tumors are uncommon beyond childhood. Controversies arise regarding the need of histological diagnosis in this eloquent area of the brain, weighting the benefits of a reliable diagnosis against the disadvantages of invasive procedures. There are scant publications about the surgical management of brainstem tumors in adults, all of them involving small retrospective cohorts. We are reporting our experience with the aim of contributing to the decision making process. Out of a series of 13 patients, 10 were approached surgically. According to Guillamo's classification the lesions were: focal (n:7), diffuse infiltrative (n:1), tectal (n:1), and exophytic (n:1). According to the Karnofsky Performance Status scale, the neurological status was = 70 in 6 cases and < 70 in 7. Histopathology was confirmed in all 10 treated cases and the samples were obtained by a direct microsurgical approach or by stereotactic biopsy. Histopathological findings were: pilocytic astrocytoma (n:1), low grade glioma (n:1), glioblastoma (n:1), cellular haemangioblastoma (n:1), subependimoma (n:1), pseudotumoral lesions (n:4; 3 cavernomas, 1 inflammatory pseudotumor), and disgerminoma (n:1). As a broad variety of pathologies could be found in this brain localization, an accurate histopathological definition can not only determine the adequate therapy, but also avoid the disastrous consequences of empiric treatments.