Cystadenocarcinoma: A malignant neoplasm derived from glandular epithelium, in which cystic accumulations of retained secretions are formed. The neoplastic cells manifest varying degrees of anaplasia and invasiveness, and local extension and metastases occur. Cystadenocarcinomas develop frequently in the ovaries, where pseudomucinous and serous types are recognized. (Stedman, 25th ed)Cystadenocarcinoma, Mucinous: A malignant cystic or semisolid tumor most often occurring in the ovary. Rarely, one is solid. This tumor may develop from a mucinous cystadenoma, or it may be malignant at the onset. The cysts are lined with tall columnar epithelial cells; in others, the epithelium consists of many layers of cells that have lost normal structure entirely. In the more undifferentiated tumors, one may see sheets and nests of tumor cells that have very little resemblance to the parent structure. (Hughes, Obstetric-Gynecologic Terminology, 1972, p184)Cystadenoma: A benign neoplasm derived from glandular epithelium, in which cystic accumulations of retained secretions are formed. In some instances, considerable portions of the neoplasm, or even the entire mass, may be cystic. (Stedman, 25th ed)Cystadenocarcinoma, Papillary: An adenocarcinoma in which the tumor elements are arranged as finger-like processes or as a solid spherical nodule projecting from an epithelial surface.Cystadenocarcinoma, Serous: A malignant cystic or semicystic neoplasm. It often occurs in the ovary and usually bilaterally. The external surface is usually covered with papillary excrescences. Microscopically, the papillary patterns are predominantly epithelial overgrowths with differentiated and undifferentiated papillary serous cystadenocarcinoma cells. Psammoma bodies may be present. The tumor generally adheres to surrounding structures and produces ascites. (From Hughes, Obstetric-Gynecologic Terminology, 1972, p185)Cystadenoma, Mucinous: A multilocular tumor with mucin secreting epithelium. They are most often found in the ovary, but are also found in the pancreas, appendix, and rarely, retroperitoneal and in the urinary bladder. They are considered to have low-grade malignant potential.Appendiceal Neoplasms: Tumors or cancer of the APPENDIX.Mucocele: A retention cyst of the salivary gland, lacrimal sac, paranasal sinuses, appendix, or gallbladder. (Stedman, 26th ed)Cysts: Any fluid-filled closed cavity or sac that is lined by an EPITHELIUM. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues.Pyonephrosis: Distention of KIDNEY with the presence of PUS and suppurative destruction of the renal parenchyma. It is often associated with renal obstruction and can lead to total or nearly total loss of renal function.Mixed Tumor, Mesodermal: A sarcoma of the body of the uterus arising in older women, composed of more than one mesenchymal tissue, especially including striated muscle cells. It is associated with previous pelvic radiation exposure in 20% of patients. (Stedman, 25th ed; Holland et al., Cancer Medicine, 3d ed, p1702)Ovarian Neoplasms: Tumors or cancer of the OVARY. These neoplasms can be benign or malignant. They are classified according to the tissue of origin, such as the surface EPITHELIUM, the stromal endocrine cells, and the totipotent GERM CELLS.Biliary Tract Neoplasms: Tumors or cancer in the BILIARY TRACT including the BILE DUCTS and the GALLBLADDER.Cystadenoma, Papillary: A benign neoplasm of the ovary.Parotid Neoplasms: Tumors or cancer of the PAROTID GLAND.Barium Sulfate: A compound used as an x-ray contrast medium that occurs in nature as the mineral barite. It is also used in various manufacturing applications and mixed into heavy concrete to serve as a radiation shield.Pseudomyxoma Peritonei: A condition characterized by poorly-circumscribed gelatinous masses filled with malignant mucin-secreting cells. Forty-five percent of pseudomyxomas arise from the ovary, usually in a mucinous cystadenocarcinoma (CYSTADENOCARCINOMA, MUCINOUS), which has prognostic significance. Pseudomyxoma peritonei must be differentiated from mucinous spillage into the peritoneum by a benign mucocele of the appendix. (Segen, Dictionary of Modern Medicine, 1992)Bile Ducts, Intrahepatic: Passages within the liver for the conveyance of bile. Includes right and left hepatic ducts even though these may join outside the liver to form the common hepatic duct.Bile Duct Neoplasms: Tumors or cancer of the BILE DUCTS.Retroperitoneal NeoplasmsPancreatic Neoplasms: Tumors or cancer of the PANCREAS. Depending on the types of ISLET CELLS present in the tumors, various hormones can be secreted: GLUCAGON from PANCREATIC ALPHA CELLS; INSULIN from PANCREATIC BETA CELLS; and SOMATOSTATIN from the SOMATOSTATIN-SECRETING CELLS. Most are malignant except the insulin-producing tumors (INSULINOMA).Tomography, X-Ray Computed: Tomography using x-ray transmission and a computer algorithm to reconstruct the image.Salivary Gland Neoplasms: Tumors or cancer of the SALIVARY GLANDS.Pancreatectomy: Surgical removal of the pancreas. (Dorland, 28th ed)Hydroxy Acids: Organic compounds containing both the hydroxyl and carboxyl radicals.Pancreaticoduodenectomy: The excision of the head of the pancreas and the encircling loop of the duodenum to which it is connected.