The neoplastic cells manifest varying degrees of anaplasia and invasiveness, and local extension and metastases occur.

Cystadenocarcinomas develop frequently in the ovaries,[1] where pseudomucinous and serous types are recognized.

Similar tumor histology has also been reported in the pancreas, although it is a considerably rarer entity representing 1–1.5% of all Pancreatic cancer.

[2][3] A cystadenocarcinoma contains complex multi-loculated cyst but with exuberant solid areas in places.

It usually presents with omental metastases which cause fluid accumulation in the peritoneal cavity (ascites).