Brief overview
- Course of disease and prognosis: Usually very good with definable tumors exclusively in the area of the ovaries; poor chances of recovery in the final stage and in the case of metastasis (infestation of organs outside the abdominal cavity)
- Treatment: surgery with removal of ovaries, fallopian tubes, uterus, large abdominal network, possibly parts of the intestine, appendix or lymph nodes; chemotherapy, rarely radiotherapy
- Causes and risk factors: Largely unknown; risk increased by genetic factors, predisposition, many female cycles, certain environmental factors; risk lower by contraception and pregnancies
- Diagnosis: abdominal palpation, ultrasound, computed tomography and/or magnetic resonance imaging, cystoscopy or rectoscopy, blood test, tissue sample
What is ovarian cancer?
Doctors distinguish between different tumor types in ovarian cancer, depending on the tissue cells from which the tumor has formed.
Epithelial tumors form the majority of tumors in ovarian cancer and develop from cells of the uppermost cell layer of the ovaries (epithelium). An example is Brenner’s tumor, which is usually benign and affects women after menopause. Rarely, this tumor is malignant. Other forms, such as serous cystadenocarcinoma or mucinous carcinoma, are clearly malignant.
Germline stromal tumors form a group of various tumors that develop from embryonic germlines or the cells of the gonads, respectively. Here, too, there are benign and malignant forms. The group of pure stromal tumors are predominantly benign.
The pure germline tumors include, for example, granulosa cell tumors (GCTs), which are considered to be of low malignancy. The group of mixed germline stromal tumors includes Sertoli-Leydig cell tumors and germline stromal tumor NOS. They cannot be clearly classified on the basis of tissue changes.
Malignant ovarian cancer quickly forms daughter tumors, so-called metastases. These spread mainly within the abdominal cavity and peritoneum. However, the liver, lungs, pleura or lymph nodes are sometimes also affected via blood and lymph channels.
Ovarian cancer: staging
The disease progresses in four stages, which are classified according to the so-called FIGO classification (Fédération Internationale de Gynécologie et dʼObstétrique):
- FIGO I: Early stage. The ovarian cancer affects only the ovarian tissue (one or both ovaries are affected).
- FIGO II: The tumor has already spread to the pelvis.
- FIGO III: The cancer has metastasized to the peritoneum (peritoneal carcinomatosis) or to the lymph nodes.
- FIGO IV: Very advanced stage. The tumor tissue is already outside the abdominal cavity (e.g., distant metastases to the lungs, reaching there via the bloodstream or lymphatic system).
Ovarian cancer mostly affects older women after menopause. According to the Robert Koch Institute (RKI), the median age of onset is 69 years. Ovarian cancer rarely occurs before the age of 40. Ovarian cancer is the second most common cancer of the female reproductive organs after breast cancer. The risk of developing a malignant tumor on the ovaries is 1.3 percent (one in 76 women is affected).
Other ovarian tumors
Tumors also occur in the ovaries that are not due to a degeneration of the ovarian cells – such as daughter tumors of other cancers. These include Krukenberg tumor, which develops as a secondary tumor of stomach cancer.
Ovarian cancer: symptoms
You can read everything important about the typical signs of ovarian cancer in the article Ovarian cancer – symptoms.
How does ovarian cancer progress and how long can one survive?
In many cases, the tumor develops unnoticed without early symptoms, so it is difficult to say how fast ovarian cancer grows. This type of tumor is usually diagnosed only at an advanced stage.
If the cancer has already spread to the abdomen, the chances of recovery are poor. In the final stage, ovarian cancer has often affected the whole body. Organs outside the abdominal cavity such as the liver and lungs then also contain metastases. At this stage, the average life expectancy is only 14 months. In patients with advanced ovarian cancer, the disease often comes back after therapy is completed.
Overall, ovarian cancer has the worst prognosis of all gynecologic cancers.
What is the therapy for ovarian cancer?
Therapy for ovarian cancer involves two main procedures: Surgery and chemotherapy. In most cases, the doctor treats the patient with a combination of both. Which therapy procedure is used depends on the stage of the tumor.
Surgery
The operation also serves diagnostic purposes. The physician has the opportunity to search the entire abdominal cavity for metastases. If, for example, conspicuously enlarged lymph nodes are present, he usually takes tissue samples for further examination.
Chemotherapy
The operation is usually followed by chemotherapy. The treatment is intended to prevent tumor foci that may not have been removed or not completely removed from developing further. The drugs (cytostatics) either affect the entire body or can be delivered specifically to the abdominal cavity. They kill cancer cells. The most effective against ovarian cancer are platinum-containing agents such as carboplatin, which is given in combination with other agents such as paclitaxel.
There are additional drugs that specifically interfere with certain characteristics of the tumor to help chemotherapy work. Substances that suppress the formation of new blood vessels, for example, worsen the supply of oxygen and nutrients to the tumor, thereby slowing its growth.
If the tumor on the ovary is diagnosed very early, chemotherapy may not be necessary.
What triggers ovarian cancer?
Like almost every type of cancer, ovarian cancer develops from cells that grow uncontrollably; in this case, it is tissue cells of the ovaries. At a later stage, the tumor then forms metastases that spread to surrounding tissue, such as the abdominal cavity. It is not known in detail why the cells degenerate. However, genetic factors seem to play a role, because ovarian cancer runs in families and certain genetic changes (mutations) occur more frequently in female cancer patients.
In addition, the number of female menstrual cycles plays a role in the development of the disease. Women with a late first menstrual period and an early onset of menopause are therefore less likely to develop an ovarian tumor. This also applies to women who have been pregnant one or more times or who have used hormonal contraception continuously over a longer period of time.
Genetic and environmental factors
Women whose first-degree relatives have had breast or ovarian cancer are at increased risk of developing the disease. Harmful environmental influences and an unhealthy diet may also play a role. There is evidence that being overweight (obesity) increases the risk of developing the disease.
How is ovarian cancer diagnosed?
The first indication of an ovarian tumor is provided by palpation of the abdominal wall and the female reproductive organs. This is usually followed by an ultrasound examination (sonography) of the abdominal region and the vagina. This provides information about the size, location and condition of the cancerous tumors. It may already be possible to assess whether the tumor is benign or malignant.
The extent to which the disease has already spread can be determined with the help of a computer tomography or magnetic resonance imaging (CT/MRI). These procedures help to detect metastases in the chest or abdominal cavity.
If there is a suspicion that the tumor has already affected the bladder or rectum, a cystoscopy or rectoscopy will provide information.
A definite diagnosis is only possible after examination of a tissue sample (biopsy), which the doctor first removes surgically.
For ovarian cancer, there is no legally required screening for prevention. Regular gynecological examinations and a vaginal ultrasound as part of cancer screening may help to detect the cancer at an early stage. Also under discussion is whether a blood test in combination with ultrasound will become a standard procedure to provide early indications of ovarian cancer.
