Ovarian cancer – Frequently Asked Questions I

Ovarian cancer – Frequently Asked Questions I

What is Ovarian Cancer?

Ovarian cancer is a type of cancer that begins in the ovaries. The female reproductive system contains two ovaries, one on each side of the uterus.The ovaries — each about the size of an almond — produce eggs (ova) as well as the hormones estrogen and progesterone.

Ovarian cancer is when abnormal cells in the ovary begin to multiply out of control and form a tumor. Some tumors are benign (non-cancerous). Others are malignant (cancerous.) Ovarian tumors may be either solid or cystic (fluid-filled sacs). They can look very similar in appearance to benign ovarian cysts, which are very common, and this can make early diagnosis difficult.

If left untreated, the tumor can spread to other parts of the body. This is called metastatic ovarian cancer.

Ovarian cancer often has warning signs, but the earliest symptoms are vague and easy to dismiss. Hence only 20% of ovarian cancers are detected at an early stage and majority are diagnosed in advanced stage of the disease.

Is ovarian cancer deadly?

Ovarian cancer is considered to be the deadliest among all gynaecological cancers. There are no specific symptoms that can help in diagnosing ovarian cancer early.

Symptoms often develop late, when the cancer is already advanced, and hence ovarian cancer has been called the “silentkiller” or “the cancer that whispers.”

Survival rates for ovarian cancer vary depending on many different factors, including the age of the woman and the stage at the time of diagnosis. Unfortunately, most cases with ovarian cancer are not diagnosed until the disease is advanced and has metastasized. In general, 75% of women survive ovarian cancer at least 1 year after diagnosis.

A 5-year survival rate is an estimate based on the percentage of people who are still alive 5 years after their cancer is diagnosed. Survival rates are slightly different for epithelial, germ cell, and stromal ovarian cancer, but on average:

• 5-year survival rates are over 90% if the cancer is still confined to the ovary at diagnosis. However, only 15% of ovarian cancers are found at this stage.
• For Stage II cancer, the 5-year survival rate is approximately 65% to 70%.
• For Stage III cancer, the 5-year survival rate is approximately 36% to 46%.
• If the cancer has spread to sites outside the pelvis, the 5-year survival rate is below 20%.

What are the stages of ovarian cancer?

Staging is the process of finding out how much cancer is in a person’s body and where it’s located or how much it has spread.

Stage I: Cancer is found in one or both ovaries.

Only 15% of all cases of ovarian cancer are diagnosed when they are Stage I.

Stage II: Cancer is found in one or both ovaries and has spread into other areas of the pelvis.

Stage II ovarian cancer is a small group, compromising 10% of ovarian cancer diagnoses.

Stage III: Cancer is found in one or both ovaries and has spread outside the pelvis to other parts of the abdomen and/or nearby lymph nodes. Cancer that has spread to the surface of the liver is also considered stage III ovarian cancer.

60% of all cases of ovarian cancer are diagnosed when they are Stage III.

Stage IV: In stage IV, cancer has spread beyond the abdomen to other parts of the body, such as the lungs or tissue inside the liver.  Cancer cells in the fluid around the lungs is also considered stage IV ovarian cancer.

15% of all ovarian cancer cases are diagnosed in stage IV.

How fast does ovarian cancer grow?

Ovarian cancer grows quickly and can progress from early to advanced stages within a year. It has been scientifically studied that ovarian cancer can progress from stage to stage in a matter of months, making it far more aggressive than malignancies such as breast cancer.

Paying attention to symptoms can help improve a woman’s chances of being diagnosed and treated promptly. Detecting cancer while it is still in its earliest stages may help improve prognosis.

Types of ovarian cancer

The type of cell where the cancer begins determines the type of ovarian cancer you have. Ovarian cancer types include:

• Epithelial tumors, which begin in the thin layer of tissue that covers the outside of the ovaries. About 90 percent of ovarian cancers are epithelial tumors.
• Stromal tumors, which begin in the ovarian tissue that contains hormone-producing cells. These tumors are usually diagnosed at an earlier stage than other ovarian tumors. About 7 percent of ovarian tumors are stromal.
• Germ cell tumors, which begin in the egg-producing cells. These rare ovarian cancers tend to occur in younger women.

What are the symptoms of ovarian cancer?

Ovarian cancer is commonly thought to be a silent killer or the cancer that whispers. This is because early stage ovarian cancers have almost none or very minimal symptoms.

Small ovarian tumors are often without any symptoms and are usually discovered incidentally during investigations for other conditions.

A larger ovarian tumor can cause genitourinary symptoms, including urinary frequency, and dyspareunia. Sometimes ovarian masses can cause bowel symptoms like constipation. These symptoms can occur in both benign disease and early ovarian cancer. It is impossible to differentiate a benign from a malignant ovarian mass by clinical examination alone.

An ovarian mass can sometimes cause sudden onset of abdominal pain and can become a surgical emergency. This can be due to rupture, torsion, and possible hemorrhage (bleeding) inside a cyst, which distends it, or by the rupture of a blood-filled cyst, causing hemoperitoneum.

Symptoms of advanced ovarian cancer are more varied. These can be fatigue, early satiety, and loss of appetite. Sometimes there may be bloating and diffuse, dull, constant abdominal pain.

What are the signs of late stages of ovarian cancer?

The clinical presentation of advanced ovarian cancer is varied. Treating doctors are often surprised by how few symptoms women with advanced ovarian cancer may experience. Nonspecific symptoms associated with advanced ovarian cancer include anorexia, fatigue, nausea, belching, early satiety, and loss of appetite.

Often patients may have bloating and diffuse, dull, constant abdominal pain, changes in the frequency of bowel movements, with alternating constipation and diarrhea. Sometimes, patients with advanced ovarian cancer present with deep venous thrombosis (DVT) i.e formation of blood clots in the deep vein of legs and lower abdomen which leads to swelling of one or both legs. DVT occurs due to large tumors pressing on pelvic veins or as part of the hypercoaguable state which is increased tendency to form blood clots associated with advanced-stage cancer.

Causes and risk factors of ovarian cancer

About 20% of high-grade ovarian cancers arise in women who carry heritable germline mutations in cancer susceptibility genes—predominantly BRCA1 or BRCA2. These women have Hereditary ovarian cancer where multiple female relatives suffer from Breast and Ovarian cancer.

The rest majority of ovarian cancer is sporadic and arises due to accumulation of somatic genetic mutations.

There are many risk factors which increase the risk of having ovarian cancer.

Age

Older women have a higher risk for ovarian cancer than younger women. Ovarian cancer usually occurs after menopause, although it can develop in women of all ages. Most women diagnosed with ovarian cancer are older than age 55.

Family History

Women are at high risk for ovarian cancer and for harboring a genetic mutation such as BRCA if they have a:

• First-degree relative (mother, sister, or daughter) with ovarian cancer at any age. The risk increases with the number of affected first-degree relatives.
• First-degree relative or two second-degree relatives (aunts or grandmothers) on the same side who had breast cancer before age 50 years.
• Family member with both breast and ovarian cancer.
• Family history of male breast cancer.
• Family history of hereditary non-polyposis colorectal cancer known as Lynch syndrome.

When a woman describes her family history to her doctor, she should include the history of cancer in women on both the mother’s and the father’s side. Both are significant.

Genetic Mutations

Inherited mutations in the genes called BRCA1 and BRCA2 greatly increase the risk for ovarian and breast cancers. While these mutations are more common among women of Ashkenazi Jewish ancestry, they can occur in women of any ethnicity.

Women with a BRCA1 mutation have about a 44% lifetime risk for ovarian cancer. Women with a BRCA2 mutation have about a 17% lifetime risk for ovarian cancer. (By contrast, the lifetime ovarian cancer risk for women in the general public is about 1 in 55 or 1.3%.)

These gene mutations are also associated with increased risks for breast cancer, fallopian tube cancer, pancreatic cancer, and prostate cancer in the male.

In addition to an increased lifetime risk, women with these gene mutations tend to develop these cancers at an earlier age than that seen in the usual population of women with ovarian cancer.

Other genetic factors are also associated with increased risk. Women who have genetic mutations associated with hereditary non-polyposis colorectal cancer (HNPCC or Lynch syndrome) have about a 10% to 15% lifetime risk of developing ovarian cancer.

Personal Medical History

Women who have been diagnosed with breast cancer are at increased risk for ovarian cancer, even if they do not have BRCA mutations.

Endometriosis, a condition in which the cells that line the cavity of the uterus grow in other areas of the body such as on the ovaries or on the other pelvic structures, increases the risk for ovarian cancer.

Reproductive History

Women are at increased risk for ovarian cancer if they began menstruating at an early age (before age 12), have not had any children, had their first child after age 35, or experienced early menopause (before age 50).

There are also preventive factors associated with reproductive history. The more times a woman gives birth, the less likely she is to develop ovarian cancer. Breast-feeding for a year or more after giving birth may also decrease ovarian cancer risk.

Tubal ligation, a method of sterilization that ties off the fallopian tubes, is associated with a decreased risk for ovarian cancer. Similarly, hysterectomy, the surgical removal of the uterus, may decrease risk.

Hormone Use

Women who use hormone therapy (HT) after menopause for longer than 5 years may have an increased risk for ovarian cancer. The risk seems to be particularly significant for women who take estrogen-only HT. The risk is less clear for combination estrogen-progestin HT.

Oral contraceptives (birth control pills) significantly reduce the risk of ovarian cancer, in some series by as much as 50%. The longer a woman takes oral contraceptives the greater the protection and the longer protection lasts after stopping oral contraceptives.

Obesity

Women who are obese have an increased risk for ovarian cancer.