Ovarian Cancer

Description

Prognosis

Ovarian cancer ranks behind lung, breast, and colorectal cancer as the fourth most common cause of female cancer death in this country. About 16,090 American women are expected to die from ovarian cancer in 2004.

In general, overall five-year survival rates (all stages combined) increased from 37% in 1974 to greater than 50% currently. Survival rates vary depending on different factors, including age and the stage at which it is detected.

The survival rate also varies according to the cancer stage:

• Five-year survival rates are over 90% if the cancer is still confined to the ovary at diagnosis.
• If it has spread to nearby regions in the pelvis, the survival rate drops to between 60% and 80%.
• If it has spread to sites outside the pelvis, the five-year survival rates are only 10% to 30%.

Unfortunately, most patients with ovarian cancer are not diagnosed until the disease is advanced, which typically involves spread to the upper abdomen. In order to establish a prognosis and determine treatment, the physician needs to know the cell type, stage, and grade of the disease.

Prognosis by Cell Type

About 90% of ovarian epithelial cancers fall into one of four major subtypes based on their origin and shape as viewed under a microscope:

• Serous. (This is the most common type.)
• Endometrioid. (This is sometimes associated with endometriosis and tends to have a more favorable outlook.)
• Mucinous. (The presence of malignant mucinous cells indicates a poorer outlook if the disease is advanced.)
• Clear cell. (Clear cell carcinomas are the most difficult to treat even when the malignancy is still confined to the ovary.)

The remaining 10% of common epithelial cancers are referred to as undifferentiated, because their exact cell of origin cannot be determined microscopically. These epithelial ovarian carcinomas tend to grow and spread quickly.

Prognosis by Stage

Cancers are staged (I through IV) according to whether they are still localized (remaining in the ovary) or have spread beyond the original site.

Prognosis by Grade

Tumors are also graded according to how well or poorly organized they are (their differentiation). Ovarian tumors are graded on a scale of 1, 2, or 3. Grade 1 tends to closely resemble normal tissue and has a better prognosis than grade 3, which indicates very abnormal, poorly defined tissue.

Other Prognostic Factors

Age. It is commonly thought that younger women have a better prognosis than older women, although a 1996 study indicated that the stage and grade of the tumor were the main factors in prognosis, while age itself played no role.

BRCA Carriers. Some studies have reported that women who carry mutated BRCA genes may have better survival rates than non-carriers. The survival advantages may be due to having a slower course or being more responsive to therapies than sporadic ovarian cancers, although this is controversial.

Angiogenesis. Experimentally, the level of biochemicals stimulating the formation of new blood vessels that support tumor growth (angiogenesis) appears to correlate with prognosis. The more angiogenic factors present in a tumor population, the more new blood vessels will form, encouraging both tumor growth and metastasis.

Hormone Receptor. In one 2000 study, women with ovarian cancer cells with progesterone receptors had higher survival rates than those with estrogen, both progesterone and estrogen, or no hormone receptors. Nevertheless, assessment of hormone receptor status is not usually necessary in ovarian cancer management.

Overexpression of p53 Mutations. High levels of a defective p53 gene (which regulates cell growth) are associated with a poorer outlook.

Consequences for Survivors

Women who survive ovarian cancer have a high risk for psychological stress. Support groups can be very helpful and are recommended for appropriate patients.