Contributed by Eun Kyung Park1, Yun-Ho Lee1, Dong-Seok Kim1, Joong-Un Choi3, Tae-Seung Kim2, Kyu-Won Shim1
1 Department of Neurosurgery, Severance Hospital, Brain Korea 21 Project for Medical Science,
Yonsei University College of Medicine, Seoul, Korea.
2 Department of Pathology, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
3 Department of Neurosurgery, CHA University, College of Medicine, Seongnam, Korea.
CLINICAL HISTORY AND IMAGING STUDIES
A 17-year-old girl presented with a seizure which started as involuntary movement of left arm and progressed to loss of consciousness. She experienced severe headaches for three weeks prior to hospital admission. There was no previous medical history. On neurologic examination, bilateral papilledema was noted and no other neurologic deficits were detected. MRI revealed a 7x4cm heterogeneous extra-axial mass in right frontoparietal area with no vasogenic edema. The mass contained a septated cystic portion with high signal intensity on T2 and low signal intensity on T1-weighted images. The solid portion had slightly higher signal intensity on both T1 and T2-weighted images. With gadolinium enhancement, the solid portion and the cystic wall showed strong enhancement. Perfusion was elevated in the solid portion (Figures 1, 2 and 3).
A right frontoparietal craniotomy was performed and gross total resection of the tumor was achieved. On gross inspection, the tumor was an extraaxial mass with about 1cm parenchymal adhesion (Figure 4). It was highly vascularized but en bloc resection was possible due to clear margin (Figure 5). There was no connection to the ventricular system. The patient recovered uneventfully after the resection and papilledema resolved slightly. After a month from the surgery, the patient underwent tomotherapy on tumor bed with total radiation dose of 67.5 Gy fractionated for 25 times. There has been no tumor recurrence detected by MRI scans.
GROSS AND MICROSCOPIC PATHOLOGY
On gross inspection, cystic membranous parts and solid parts as well as a small piece of cerebral cortex were submitted for evaluation.
The tumor showed high cellularity, numerous mitoses and microvascular proliferation. In some areas, columnar cells were arranged around a non-vascular lumen (Figure 6). Hyperchromatic nuclei showed increased polymorphism. Tumor cells showed GFAP immunoreactivity (Figure 7) with a high Ki-67 labeling index, approximately 25% in some areas (Figure 8). The tumor cells also showed dot-like CD 99 immunoreactivity in perinuclear areas (Figure 9). There was no brain invasion in the cortical specimen adjacent to the tumor.