P17.13ABSCESUALIZED GLIOMAS: PREDICTIVE VALUE OF 99MTC-LEUKOSCAN.

Abscess formation within brain tumor is uncommon. Intrasellar or parasellar tumors are among the most common neoplasms that developed such complications as the results of direct extension of microbial flora from contiguous infected sinuses. Cerebral gliomas with abscess are extremely rare. The major challenge is detection of a correct diagnosis. The diagnosis of brain tumor associated with abscess is particularly difficult by conventional neuroradiological studies. Often, computed tomography (ct) and magnetic resonance imaging (mri) can reveal a sudden increase in size of the mass and significant perilesional edema. However, these studies did not consent a correct early diagnosis and only surgical treatment with histological examination allow the exact diagnosis. 99mtc-labeled sulesomab (leukoscan®) can be useful in the diagnosis of brain tumors with intratumoral abscess. 99mtc-labeled sulesomab (leukoscan®) consists of monoclonal murine igg antibody fab' fragment, bound with technetium-99m with affinity for a 42 kda glycoprotein present on the surface of activated granulocytes (nca-90 surface antigen). It is used in different clinical settings as a potential diagnostic tool for the infections of various tissues. We presented three rare cases of cerebral glioma showing intratumoral abscess formation. All patients had been submitted to 99mtc-leukoscan study. Labeled leukocytes scintigraphy seems to be able to differentiate infectious from non-infectious brain lesions. In our patients mri and magnetic resonance spectroscopy (mrs) were unconvincing while the results of the leukocyte scintigraphy, were successively confirmed by histopathological examination, which also showed the presence of a brain abscess. Thus in our cases the sensitivity and the positive predictive value (ppv) of the granulocyte scintigraphy were both 100%. To the best of our knowledge no data have been reported in the literature on the role of nuclear medicine investigation for the recognition of brain abscesses so far. To date this represents the first description of the role of leukoscan in cerebral gliomas with abscess formation.