Fig. 2

Representative photomicrographs of the tumor recurrence. a The tumor was well circumscribed and there was a peripheral rim of lymphoid aggregates. b At intermediate power, the tumor demonstrated marked nuclear atypia with morphology reminiscent of a pleomorphic undifferentiated sarcoma. c Very occasional cells demonstrated cytoplasmic vacuolation, morphologically suggestive of an origin from the dedifferentiation of liposarcoma. d Fluorescent in situ hybridization studies demonstrated amplification of MDM2 (red signal). Original magnifications a 20×, b 100×, c 400×, d 600×