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)
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)
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)
Any fluid-filled closed cavity or sac that is lined by an EPITHELIUM. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues.
Mixed Tumor, Mesodermal
Biliary Tract Neoplasms
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
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
Encyclopedias as Topic
Surgical excision of the gingiva at the level of its attachment, thus creating new marginal gingiva. This procedure is used to eliminate gingival or periodontal pockets or to provide an approach for extensive surgical interventions, and to gain access necessary to remove calculus within the pocket. (Dorland, 28th ed)
Sarcoma, Alveolar Soft Part
A variety of rare sarcoma having a reticulated fibrous stroma enclosing groups of sarcoma cells, which resemble epithelial cells and are enclosed in alveoli walled with connective tissue. It is a rare tumor, usually occurring between 15 and 35 years of age. It appears in the muscles of the extremities in adults and most commonly in the head and neck regions of children. Though slow-growing, it commonly metastasizes to the lungs, brain, bones, and lymph nodes. (DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1365)