|What Types Of Ovarian Cancer Are There?
Generally ovarian cancers are identified according to the type of cell the original tumor started in. The ovaries are a complex organ which is responsible for egg production (ova) and for producing estrogen and progesterone hormones. Each particular function of the ovary is carried out by a certain type of cell. Any of those cell types can turn cancerous. The three main types of cells in the ovary are:
These cells cover the ovary. 90 percent of ovarian cancers develop here, and are known as ovarian epithelial cancer.
These are found inside the ovary itself. They develop into eggs that are released every month as part of the menstrual cycle. Tumors that begin here are known as germ cell tumors and are grouped as nonepithelial cancers of the ovary. To compare survival rates according to types, see ovarian cancer survival rates.
These form the tissue which holds the ovary together. They also produce most of the female hormones. Cancer that begins here is known as stromal cancer. It is grouped as a nonepithelial cancer of the ovary. Stromal and germ-cell cancers account for about 10 percent of all ovarian cancers.
Epithelial Cancer Of The Ovary
The majority of epithelial ovarian tumors are non-cancerous (benign) and do not spread or cause a serious health issue. There are many types of benign tumors in this category including mucinous adenomas, serous adenomas and Brenner tumors.
Tumors With Low Malignant Potential (LMP)
These types of tumors in the epithelial cells are considered borderline cancer. When the LMP tumors are looked at under a microscope they do not appear to be cancerous. LMP tumors account for about 15 percent of all epithelial cancers. Nearly 75 percent are found at an early stage when they are highly treatable. They occur more commonly in younger woman - the average age of the woman is 40 compared to 53 years old for other types of epithelial cancers. LMP tumors are also different because they do not spread outside the ovaries or into the abdominal cavity; they can grow on the abdominal tissue lining but not into it. Although LMP tumors can be fatal, this would be considered a rare outcome. Determining the type of tumor present is an important part of the ovarian cancer diagnosis process.
Malignant Epithelial Tumors
If an epithelial tumor turns cancerous, it is called carcinoma. About 90 percent of all ovarian tumors which are malignant are epithelial ovarian carcinomas. The carcinomas are further subdivided according to how the tumor looks under a microscope. The subgroups are called: serous (the most common type), followed by mucinous, endometrioid and clear cell. If the cells do not look like any of the 4 sub-types then the tumor is called undifferentiated. Undifferentiated carcinomas are more dangerous because they tend to spread faster. Once a tumor has been diagnosed, doctors will also want to stage it, that is, to determine its size and location, i.e. how far advanced it is. (See Ovarian Cancer Stages).
Primary Peritoneal Carcinoma (PPC)
This is a very rare form of cancer that resembles epithelial ovarian cancer under a microscope. It is also known as extra-ovarian primary peritoneal carcinoma (EOPPC) and serous surface papillary carcinoma. It develops in the cells which line the abdomen and pelvis, this lining is called the peritoneum. PPC tends to grow and spread over the lining of the pelvis and abdomen and it is usually difficult to know where exactly it started. It can develop in women who still have their ovaries intact, but it is more of a worry for women who have had their ovaries removed in order to prevent ovarian cancer. It causes similar symptoms to ovarian cancer, such as bloating, indigestion, change in bowel habits, nausea and vomiting. It is treated in the same way as advanced stages of ovarian cancer – that is by surgery (see ovarian cancer treatment options) followed by chemo.
Fallopian Tube Cancer
Fallopian tube cancer is very rare but it can produce similar symptoms to ovarian cancer and PPC. However the treatment and long-term outlook for fallopian tube patient tends to be better than those with ovarian cancer.
Nonepithelial Cancers Of the Ovary
Germ Cell Tumors
These account for less than 2 percent of all ovarian cancers. Germ cells are involved in the development of sexual organs in a fetus. Some of these cells stop developing while the baby is still a fetus and lie dormant for years. Eventually they can give rise to both benign and cancerous (malignant) tumors inside the ovary itself. Most tumors turn out to be benign. Overall the prognosis of patients is good with 90 percent surviving 5 years after diagnosis. There are several sub-types of germ cell tumors and these are:
Also known asendodermal sinus tumor and embryonal carcinoma. It usually affects women between the ages of 10 and 30. Dysgerminomas are malignant and 25 percent have metastases at time of diagnosis (i.e. cancer has spread to distant sites). Both ovaries are usually affected and hCG and AFP blood tests are usually negative. In early stages of the disease the cure rate is 75 percent and surgery may even be able to preserve fertility. Even in advanced stages a combination of surgery and chemotherapy is effective in controlling the disease in about 90 percent of patients.
Endodermal Sinus Tumor
This is the second most common sub-type of germ cell tumors. It occurs in young women and teenagers. The most common symptom is abdominal pain. It may be noted in tests because AFP levels tend to increase although hCG tests are still negative. Girls who have the tumor removed usually have a better outlook. Chemotherapy is also applied after surgery. Radiation therapy has no effect.
Usually occurs in girls before menarche (puberty) and young women. In prepubescent girls symptoms can resemble puberty. In older girls signs include missed periods, irregular vaginal bleeding and abnormal hair growth patterns. Treatment involves surgical removal of the tumor. Adult women can have signs of ectopic pregnancy and HCG can be found in their blood and urine. Gestational choriocarcinoma is treated with surgery and chemo.
This accounts for about 4 percent of all germ cell tumors. It usually occurs in the pelvis or abdomen and most commonly in teenagers. Symptoms are similar to choriocarcinoma and treatment usually involves removing the ovary and malignant fallopian tube as well as chemotherapy.
When looked at under a microscope these germ cell tumors look like a developing embryo. It usually occurs before the age of 20 and symptoms include abnormal uterine bleeding and a tumor on the pelvis. Immature teratomas are malignant while mature teratomas are benign tumors that are known as dermoid cysts. Immature teratomas are cured by surgery or if cancer has spread chemotherapy is also applied. Dermoid cysts or mature teratomas are removed by surgery.
Only 1 percent of ovarian cancers are stromal cell tumors, the majority of which occur in women over 50. Stroma is the structure which supports organs and in the ovaries there are several types of stroma tissue. Granulosa cell and theca cells surround the ovaries themselves and cancer which forms in these cells is more common in postmenopause women. Typical signs are abdominal pain, bloating and vaginal bleeding. If a woman is still of childbearing age and wants to preserve fertility surgeons may just remove one ovary and fallopian tube. If this is not a concern then a total hysterectomy is performed. Other cells in the stroma tissue include sertoli and leydig cells. Tumors in these cells can cause male hormones to be produced causing periods to stop. They can also cause chest and facial hair to grow.
Know The Signs! Symptoms of ovarian cancer
What Is NOT Ovarian Cancer
An ovarian cyst is a sac filled with fluid that forms in or on the ovary. Cysts can occur in one or both ovaries and in women of all ages. Most ovarian cysts occur as part of the process of ovulation and these are known as functional ovarian cysts. They are not harmful and usually disappear naturally within a few months without treatment. In fact most cysts remain undiagnosed. Occasionally however they can grow to the size of an orange or larger. In such instances they can cause severe pain, particularly if they twist or rupture.
Endometriosis is a condition where cells that line the uterus attach themselves to other parts of the body such as the ovaries, fallopian tubes, pelvis, bladder or abdominal wall. Endometriosis symptoms can cause pelvic pain, painful periods (dysmenorrhea), fatigue, constipation, diarrhea and even infertility.
Fallopian Tube Masses
These are growths in the fallopian tube which may result from an ectopic pregnancy or inflammation. It is relatively rare. It can cause pain and nausea.
Bowel and Intestine Disorders
Inflammatory diseases of the intestines may produce symptoms similar to ovarian cancer such as nausea, vomiting, diarrhea and lack of appetite. There may also be pelvic pain. Bowel disorders such as inflammatory bowel disease and diverticulitis are examples of conditions which can cause these symptoms.
Kidney and Intestine Tumors
A cancerous tumor which occurs in the intestines or kidneys can produce symptoms similar to ovarian cancer. X-rays and other imaging techniques can identify the true cause.