Rare tumors of the pancreas

SPPN vary widely in size. The larger tumors may undergo cystic or hemorrhagic degeneration and occasionally have calcifications ( Fig. 46.1 ). They are typically well circumscribed and surrounded by a pseudocapsule. Histologically, the tumors show solid regions composed of nests and sheets of uniform epithelioid cells alternating with cystic spaces and pseudopapillae ( 2 ).