Gynecologic and Obstetric Pathology

Implantation Site Nodule

D efinition — A collection of extravillous trophoblasts within hyalinized stroma, indicative of a previous pregnancy. Clinical Features Epidemiology Implantation site nodules are common and typically have the same immunophenotype as epithelioid trophoblasts seen in the membranes, maternal surface, and…

Fresh Implantation Site

PITFALL D efinition — The area adjacent to the gestational sac where intermediate trophoblasts and fibrinoid can be found permeating the decidua. Clinical Features Epidemiology Normal structure. You’re Reading a Preview Become a Clinical Tree membership for Full access and…

Gestational Sac

D efinition — The membranous sac that envelops the developing embryo. Clinical Features Epidemiology The gestational sac can be identified in the majority of samples from previable pregnancies. The gestational sac confirms an intrauterine pregnancy, even in cases in which…

Malignant Mesothelioma

D efinition — Malignancy comprised of mesothelial cells. Clinical Features Epidemiology Malignant mesothelioma is an uncommon neoplasm that most often is found involving the pleura. Cases have been described within the abdomen; however, the majority of these cases have been…

Papillary Mesothelial Hyperplasia

D efinition — A benign, reactive condition consisting of hyperplastic mesothelial cells seen in association with acute and chronic irritation of the peritoneal surface. Clinical Features Epidemiology Papillary mesothelial hyperplasia is often found in cases of pelvic inflammatory disease, tubo-ovarian…

Papillary Mesothelioma

D efinition — A well-differentiated tumor of mesothelial cells. Clinical Features Epidemiology An uncommon neoplasm occurring in women between 20 and 50 years of age. Some but not all have evidence of asbestos exposure. You’re Reading a Preview Become a…

Benign Cystic Mesothelioma

D efinition — A rare benign disease consisting of multiloculated mesothelial-lined cysts in the peritoneum. Also termed “multiloculated peritoneal cyst.” Clinical Features Epidemiology Rare. Reproductive-age women. History of a prior abdominal procedure or surgery is often noted. Controversy as to…

Desmoplastic SMALL Round Cell Tumor

D efinition — A rare, predominantly intraabdominal tumor associated with a specific chromosomal translocation (t11;22)(p13:q12) that produces a fusion transcript EWS Clinical Features Epidemiology Extremely rare, particularly in women. Typically seen in children and young adults. Specific cell of origin…

Primitive Neuroectodermal Tumor

D efinition — A rare, poorly differentiated embryonal neuroectodermal tumor sometimes associated with a teratoma that mimics the central type of primitive neuroectodermal tumor (PNET). Clinical Features Epidemiology Extremely rare in the ovary. Belongs in the Ewing's family of tumors…

Gastrointestinal Stromal Tumor

D efinition — Ovarian involvement is a rare metastatic presentation of this tumor. Clinical Features Epidemiology Most common mesenchymal tumor of the gastrointestinal tract. Driven by oncogenic KIT or PDGFRA mutations. Most common is an in-frame mutation of exon 11…