Clinical information: The patient was a 40 year-old man with back pain for a long but unknown duration of time. MRI revealed a sharply circumscribed, lobulated, brightly enhancing, 3 cm mass in the cauda equina. The mass was removed and the followings are representative photomicrographs from the specimen. Panel A to C are taken from intraoperative cytologic preparation, D and E are taken from frozen section, F to H are taken from permanent sections.             

A. Squash	B. Squash	C. Squash	D. Frozen
G. Frozen	H.	I.	J.

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