What is ovarian cancer?
Ovarian cancer is composed of several different tumor types, including epithelial, stromal, and sex cord tumors. Epithelial cancers are the most common, and tend to occur in older patients, whereas stromal and sex cord tumors are more common in younger patients, and are occasionally found in children.
One in 70 women in the U.S. will develop ovarian cancer. It ranks behind lung, breast, colorectal, and pancreatic cancers as the leading cause of cancer deaths in U.S. women.
When ovarian cancer is diagnosed at an early stage, and the disease is confined to the ovaries, surgery can result in a cure rate greater than 90%.
Unfortunately, ovarian cancer is most often diagnosed at advanced stages, when the cancer has spread into the upper abdomen. This late diagnosis, occurring in up to 75% of cases, is due to the vague nature of signs and symptoms of the disease’s early stage that may go undetected.
Recent advancements in the management of ovarian malignancies have significantly improved the prognosis for this cancer. Today, ovarian cancer is often characterized as a chronic disease because more women are living with this cancer for a longer period of time than ever before.
What are the risk factors for ovarian cancer?
Approximately 90% of women who develop ovarian cancer have sporadic mutations that occur within their own lifetime.
Approximately 10% of women who develop ovarian cancer have a germ line mutation, which is an abnormal gene inherited from either her mother or father, that greatly increases the lifetime risk of developing breast and/or ovarian cancer.
For those 10% with a gene abnormality, a positive family history usually signals that an inherited defect is present. A positive family history is defined when there are two or more first- or second-degree relatives with breast and/or ovarian cancer, and the breast cancer is diagnosed prior to age 50. Candidates for genetic counseling usually have such a positive family history with at least some affected at an early age, or with bilateral tumors or multiple primary cancers.
Genetic counseling and a carefully conducted family history can help identify an individual's risk of carrying a cancer gene. The American Society of Clinical Oncology has recommended that mutation testing be offered to individuals where the probability of identifying BRCA1 (Breast Cancer I, susceptibility protein) and BRCA2 (Breast Cancer 2, susceptibility protein) mutations is 10% or greater based on family history. Both genetic counseling and genetic testing services are readily available through the Division of Gynecologic Oncology at Columbia University.
Those women who are found to carry an abnormal cancer gene have a number of surgical and non-surgical options that may greatly decrease their chances of developing breast and/or ovarian cancer.
In terms of risk reduction, oral contraceptive pill (OCP) use significantly decreases the lifetime risk of developing ovarian cancer. Using OCPs for at least three years can cut this risk approximately in half.
What are the symptoms of ovarian cancer?
Common symptoms include bloating, increased abdominal size, indigestion, nausea, decreased appetite, and vague abdominal pain. Occasionally vaginal bleeding, pelvic pressure, back pain, frequent urination, and constipation may be observed.
Early diagnosis is an area of active investigation and research. Physicians do not yet have an effective screening test to diagnose early ovarian cancer. Pelvic ultrasound, physical exam and a tumor marker known as Ca-125 are available tools, but their sensitivity and specificity are not high enough to be used widely to screen the general population.
Advances in diagnostic techniques are promising, including proteomics, a test which measures key proteins in the blood to determine early ovarian cancer. Available protocols should be discussed with your physician, especially if you are at increased risk due to positive family history of breast or ovarian cancer.
How is ovarian cancer treated?
Initial treatment of ovarian cancer is usually surgical. Goals of surgery include:
- Determining the origin of the tumor
- Staging, or determining the extent of tumor spread, which often includes removal of lymph nodes, omentum (a fatty apron that is attached to the colon), and other biopsies in the abdomen and pelvis.
- Cytoreduction or Debulking--removing as much of the tumor as possible when it has spread beyond the ovaries. Sometimes portions of the bowel or other organs are removed, in addition to the reproductive organs. The ideal outcome is to remove all visible diseased tissue, although it may be impossible to achieve this goal. Patients are divided into optimal and suboptimal strata following surgery, based on the amount of disease left behind. If the remaining tumor implant is less than 1 cm then patients are defined as optimally cytoreduced, whereas implants greater than 1 cm l defines suboptimal disease status.
Surgery may be performed using minimally invasive techniques. Treatment may include several cycles of chemotherapy prior to surgery in some cases. This approach is called neoadjuvant chemotherapy. Options should be discussed with your surgeon.
Subsequent treatment depends on the patient’s overall medical condition, the cancer's stage, the type of cancer, and the residual cancer remaining after the surgery. Treatment may include chemotherapy medications, radiation, immunotherapy, and even additional surgery. Each treatment plan is individualized to minimize complications while maximizing quality and length of life.