About Ovarian Cancer
Cancer Basics
Cancer is not a single disease, but a category of many distinct diseases.
Normally, cells divide only when additional cells are required for normal body function. However, sometimes the controls that regulate when a cell divides stop functioning. This results in the disordered accumulation of cells that eventually grow into a mass called a 'tumor'.
Not all tumors are cancerous. Tumors that are cancerous have one or more of three malignant properties:
1. Uncontrolled cell growth (division beyond the normal limits)
2. Cell invasion (intrusion on and destruction of adjacent tissues)
3. Metastasis (cells spread to other locations in the body via lymph or blood)
These three properties differentiate malignant (cancerous) tumors from benign tumors, which are self-limited, do not invade, and do not metastasize.
Ovarian Cancer: The Facts
The cause of ovarian cancer is unknown. Ovarian cancer usually occurs in women over age 50, but it can also affect younger women. About 22,000 women in the United States are diagnosed with ovarian cancer each year, and 15,000 women will die from it. Ovarian cancer is difficult to detect early because symptoms are generally mild and women often do not notice them until the disease is in an advanced stage. Only 24 percent of ovarian cancers are detected at an early stage.
There are three main types of ovarian tumors, but epithelial ovarian tumors (derived from the cells on the surface of the ovary) make up almost 90 percent of ovarian cancers. The Clearity Foundation is dedicated to treating epithelial ovarian cancer.
For more information on epithelial ovarian tumors, click here
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Epithelial ovarian tumors are also classified into subtypes based on the type of epithelial differentiation that is present in the tumor. The subtypes include serous, mucinous, endometrioid, clear cell, and transitional cell. The subtypes derive their names from the tissue that they most closely resemble: | |
Type of differentiation |
Tissue that tumor most closely resembles |
Serous |
Fallopian tube epithelium |
Mucinous |
GI tract or endocervical epithelium |
Endometrioid |
Proliferative endometrium |
Clear cell |
Gestational endometrium |
Transitional cell (Brenner) |
Urinary tract epithelium |
Staging is an assessment of how far the tumor has spread.
Stage I - Growth of tumor limited to the ovaries
II - Growth of tumor in one or both ovaries
Stage III - Tumor involving one or both ovaries with peritoneal implants outside the pelvis and/or positive retroperitoneal or inguinal lymph nodes. Superficial liver metastasis equals Stage III.
Stage IV - Growth involving one or both ovaries with distant metastases. If pleural effusion is present there must be positive cytology to allot a case to Stage IV. Tumor spread inside the liver equals Stage IV.
Recurrent/Refractory - Recurrence means that the tumor has returned after initial therapy. Refractory means that the tumor fails to respond to initial treatment.
If the cancer is within Stage I or Stage II (confined to the ovaries), diagnosed, and treated early, the five-year survival rate is around 90%. If diagnosed in Stage III or higher, the survival rate can be less than 30%. Standard treatment is usually surgery followed by treatment by chemotherapy drugs Taxol, Cisplatin, or Carboplatin.
For more in-depth information about ovarian cancer, the following sites may be useful:
National Cancer Institute
http://www.cancer.gov/cancertopics/types/ovarian
MD Anderson Hospital
www.mdanderson.org/diseases/Ovarian
National Comprehensive Cancer Network
http://www.nccn.org/default.asp
The Oncology Channel
www.oncologychannel.com
Epithelial tumors also exhibit a spectrum of behavior: |
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Degree of benignancy/malignancy |
Pathologic Features |
Benign |
Simple, non-stratified epithelium, with no cytologic atypia |
Atypical proliferative tumor (low malignant potential, borderline) |
Epithelial proliferation with stratification and tufting, variable mitotic activity and nuclear atypia, no stromal invasion |
Malignant (Carcinoma) |
Stromal invasion and cytologic atypia |