Papillary glioneuronal tumor (PGNT) is a low-grade biphasic neoplasm with astrocytic and neuronal differentiation. This tumor occurs most commonly in the frontal and temporal lobes, close to the ventricles, and rarely in the cerebellum, brainstem, and pineal gland. However, there has been no report of this tumor in the suprasellar region to date. In this paper, we report a case of PGNT in the suprasellar region in a 16-year-old girl. Magnetic resonance imaging (MRI) revealed a cystic tumor with calcification that progressed from the anterior skull base to the suprasellar and temporal regions. Preoperatively distinguishing this tumor from craniopharyngioma was difficult because of the patient’s age, localization of the tumor, and neuroimaging results. This case showed a backward shift of the chiasma, which is observed in only 4.7% of craniopharyngioma, as well as normal endocrine findings. Endocrinological examination and an MRI evaluation of the chiasmal shift may be useful for discrimination.

Background: Rosette formation is a rare morphological feature in meningiomas. It can be seen in angiomatous, meningothelial, transitional, secretory, papillary or rhabdoid subtype; however there are very few reports of meningiomas with rosettes, and the feature itself is not criterion for the WHO grade, so this feature sometimes makes the diagnosis difficult. Case presentation: A 62 y old Japanese woman stumbled and was admitted to a hospital. Magnetic resonance imaging showed a 50 mm extra-axial tumor on the right cerebral falx. Histologically, the tumor contained multiple rosettes that had a central nuclear-free zone without a vessel core. It also showed a sheet-like or whorled growth pattern and pseudopapillary structure. Some round tumor cells had abundantly dense eosinophilic cytoplasm, displaying rhabdoid features. High cellularity, small cells with a high nuclear-to-cytoplasmic ratio and prominent nucleoli were recognized, but the mitotic activity was less than 1/10 high-power fields. The tumor was immunohistochemically positive for EMA and synaptophysin (weakly) but negative for GFAP, progesterone, STAT6, S-100, NeuN and melan A. The Ki-67 labeling index was merely 0.5%. Although ependymoma was considered as the first differential diagnosis, it was ruled out, as perivascular pseudorosettes and ependymal rosettes were not seen. We ultimately made a diagnosis of atypical meningioma with a rosette-like and pseudopapillary pattern, WHO grade II. Discussion and conclusion: The meningiomas in this case showed remarkable rosette formation, but as this is not criterion for deciding WHO grade, grading was diagnostically difficult. Papillary meningioma was also considered as a critical differential diagnosis; however, our final diagnosis was made after considering the very low mitotic activity and Ki-67 labeling index, which were not consistent with WHO grade III. This case was very unique and diagnostically difficult. This report may be an aid for the diagnosis of pathologically unusual entity.

Optic nerve avulsion is an exceedingly rare condition. Here, we describe a case of optic nerve avulsion in a 74-year-old man with temporal hemianopia in the contralateral eye after a bear attack. Magnetic resonance imaging (MRI) revealed separation of the optic nerve distal to the optic chiasma, whereas the high signal in diffusion-weighted imaging suggested nerve injury from the left side of the optic chiasma to the left optic tract. MRI slices parallel to the optic chiasma were obtained and used for evaluating the site of optic nerve avulsion and nerve injury, which were responsible for temporal hemianopia in the contralateral eye.

No abstract

BACKGROUND Pediatric meningiomas are rare, and only a few cases attributed to trauma and characterized by development at the site of bone fracture have been reported. Both pediatric and traumatic meningiomas have aggressive characteristics. OBSERVATIONS An 11-year-old boy who sustained a head injury resulting from a left frontal skull fracture 8 years previously experienced a convulsive attack. Imaging revealed a meningioma in the left frontal convexity. Total removal of the tumor with a hyperostotic section was successfully achieved. Intraoperative investigation showed tumor invasion into the adjacent frontal cortex. Histologically, the surgical specimen revealed a transitional meningioma with brain invasion and a small cluster of rhabdoid cells. This led to a final pathological diagnosis of an atypical meningioma with rhabdoid features. The postoperative course was uneventful, and no recurrence of the tumor was found after 2 years without adjuvant therapy. LESSONS This is the first report of a pediatric meningioma with rhabdoid features occurring at the site of a skull fracture. Meningiomas that contain rhabdoid cells without malignant features are not considered to be as aggressive as rhabdoid meningiomas. However, the clinical course must be carefully observed for possible long-term tumor recurrence.

No abstract

No abstract