Multifocal Medulloblastoma in an Adult Patient: Description of a Rare Presentation and Review of the Literature.

Medulloblastoma is an embryonal neuroepithelial tumor that affects mainly childhood and more rarely adults. Medulloblastoma occurring as multiple nodules at diagnosis is a rare and tricky presentation. Here, we describe the case of a previously healthy 47-year-old woman with multiple posterior fossa cerebellar tumors. Histological, immunohistochemical, and molecular analyses were performed to best characterize the two excised lesions. The histopathological analysis revealed different variants of medulloblastoma in the excised nodules, one being extensive nodularity, rare in adults, and the other desmoplastic/nodular with areas of anaplasia. Immunostains and molecular analysis classified both nodules as SHH medulloblastoma. Adult medulloblastoma is extremely rare. Important differences exist between adult medulloblastoma and medulloblastoma arising in children and infants. Such differences are in location, distribution of histological variants and of molecular subgroups, survival rates, and therapeutic options. An extensive morphological and molecular characterization of such rare tumors is necessary to choice the best-tailored therapy.

Spindle cell oncocytoma: Report of two cases with massive bleeding and review of the literature.

Spindle cell oncocytoma (SCO) is a rare pituitary tumor, classified as a WHO grade I neoplasm. Due to its rarity, SCO is often preoperatively misdiagnosed as a pituitary macroadenoma. In the present study we report two recent cases of SCO, a 61-year-old male and a 65-year-old female presenting at Treviso General Hospital between March 2014 and April 2015. Tumor resection was achieved by endoscopic transsphenoidal approach but massive hemorrhagic events hampered surgery, endangering the patient's life in both cases. Both tumors featured fascicles of spindle cells with eosiniphilic cytoplasm expressing vimentin, S-100 and thyroid transcription factor-1 (TTF-1). The diagnosis of SCO was confirmed by second opinion in both cases. Extensive review of available literature, about 30 cases from 2002 to 2015, provided valuable clinical data for preoperative diagnosis and surgical removal of SCO tumors.

Primary and metastatic intraaxial brain tumors: prospective comparison of multivoxel 2D chemical-shift imaging (CSI) proton MR spectroscopy, perfusion MRI, and histopathological findings in a group of 159 patients.

BACKGROUND: This study aims to assess the diagnostic value of multivoxel 2D chemical-shift imaging (CSI) proton magnetic resonance (MR) spectroscopy combined with perfusion magnetic resonance imaging (MRI) in the differential diagnosis and grading of brain tumors by comparing neuroimaging data with histopathological findings obtained after resection or biopsy. METHODS: A total of 159 patients with a previous brain tumor diagnosis underwent multivoxel 2D CSI proton MR spectroscopy and perfusion MRI. MR spectroscopy multivoxel 2D CSI was performed with an echo time of 30, TR 1,500, FOV 160 mm, acquisition time 7 min 34 s. rCBV maps were evaluated during postprocessing. Statistical analysis was performed on the examination of distributive normality, with logarithmic transformations, Fisher's test, and Bonferroni's test. We used the Pearson's test to compare percentages. RESULTS: In the differential diagnosis between GBM and metastases, MR spectroscopy multivoxel 2D CSI, combined with dynamic contrast enhanced MRI (DCE-MRI) perfusion, reached high sensibility and specificity (p < 0.000001). In brain tumor grading, the same method reached high sensibility and specificity (p < 0.000001) in distinguishing grade III-IV gliomas but encountered difficulty in determining grades within the two main groups of primary brain tumors, especially where mixed gliomas were involved. CONCLUSIONS: The systematic use of CSI spectroscopy and perfusion imaging has shown a high potential in the differential diagnosis and grading of brain tumors. Further exploration into diagnostic procedures that can significantly distinguish between grade III-IV and grade II tumors is needed.