Ovarian tumors, or ovarian neoplasms, are tumors in the ovary. Not all are ovarian cancer. They consist of mainly solid tissue, while ovarian cysts contain fluid.
In 2020, the World Health Organization (WHO) divided ovarian cancerous tumours as 90% epithelial, 3% germ cell, and 2% sex cord-stromal types.
Histopathologic classification
Tumor of the ovary vary remarkably as they may arise from any of the 3 cell types of the normal ovary.
Ovarian tumors are classified according to the histology of the tumor, obtained in a pathology report. Histology dictates many aspects of clinical treatment, management, and prognosis.
The most common forms are:
Type Subtype Relative incidenceUnless otherwise specified in boxes, reference is: Percent malignant Comments Micrograph Germ cell tumor Mature cystic teratoma 46.0% 0.17% to 2% Cystic, with elements of all 3 germ layers (endoderm, mesoderm and ectoderm). Topic Completed: 1 November 2016. Revised: 4 April 2019 Immature teratoma 2.5% 100% A teratoma that contains anaplastic immature elements, and is often synonymous with malignant teratoma. Other germ cell tumors 3.0% Others mainly include dysgerminoma, yolk sac tumor, struma ovarii and squamous cell carcinoma arising from a dermoid cyst, and malignant mixed germ cell tumor. Surface epithelial-stromal tumor Serous tumor 25% 18.5% Benign serous tumors of the right ovarian cyst are thinwalled unilocular cysts that are lined by ciliated pseudostratified cuboidal or columnar epithelium. Mucinous tumor 15% 8.8% Benign mucinous tumors of the ovary consist of simple, nonstratified columnar epithelium with basally-located hyperchromatic nuclei and resemble gastric foveolar epithelium. Endometrioid tumor 1% Almost 100% Tubular glands, resembling endometrium. Topic Completed: 1 December 2012. Revised: 6 March 2020 Other surface-epithelial tumors 1.5% Others include mainly malignant mixed Müllerian tumor, Brenner tumor and mixed epithelial tumor. Sex cord-stromal tumor Ovarian fibroma 1.5% 0% Spindle-shaped fibroblastic cells and abundant collagen. Adult granulosa cell tumor 1% Almost 100% Small, bland, cuboidal to polygonal cells in various patterns. Topic Completed: 1 December 2012. Revised: 9 March 2020 Other sex cord-stromal tumors 1% Others include mainly juvenile granulosa cell tumor, thecoma and sclerosing stromal tumor Secondary/metastatic) tumor 2% 100% Usually from breast cancer, colon cancer, endometrial cancer, stomach cancer or cervical cancer.
Mixed tumors contain elements of more than one of the above classes of tumor histology.
History An 1882 article appearing in Scientific American mentions the case of a patient at University of Pennsylvania Hospital when Dr. William Goodell removed a 112 lbs tumor from a 31 year old patient, who weighted 75 lbs after removal from the tumor.
See also International Ovarian Tumor Analysis trial
References