What is Ovarian Cancer?

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Ovarian cancer is one of the most deadly tumours for women. Many cases are diagnosed in advanced stages of the disease. The treatment usually consists of a combination of surgery and chemotherapy.  

Ovarian cancer explained in first person

Professionals and patients explain how you live with the disease
Knowing that it is a silent disease, meaning it does not show symptoms, and when it does it is usually very late. This means patients should examine themselves, know their bodies, and go to all their scheduled gynaecological check-ups.
I had a vaginal ultrasound, but a little more extensive, and they then told me I had ovarian cancer, an ovarian carcinoma in both ovaries. So they had to act fast.

The term ovarian cancer (OC) is used to describe cancers that originate in cells from the ovary, fallopian tubes, or peritoneum (the membrane that covers the inside walls of the abdominal cavity). Ovarian cancer arises when cells in the ovaries or fallopian tubes grow abnormally and multiply to form a lump or tumour.  

Cancer of the fallopian tubes was once thought to be rare, but it is now known that most cancers (high-grade serous epithelials) begin at the outer end of the fallopian tube, near the fimbriae.  

Most ovarian tumours are benign and many go away on their own.  

When an ovarian tumour is detected (in an ultrasound), various tests are performed on the patient to assess whether the tumour is malignant and to decide on treatment. In some cases, surgery (removal of the cyst or ovary) is required to obtain a definitive histological diagnosis.   

Malignant ovarian tumours often do not cause patients any discomfort until the advanced stages, leading to a late diagnosis and a worse prognosis. Some symptoms are rather non-specific, such as a feeling of discomfort or abdominal swelling.   

Types of Ovarian Cancer

There are various types of ovarian cancer and these are grouped into several categories according to how they look under the microscope. 

Borderline or low malignant potential tumours. These are a group of tumours with a better prognosis than invasive ovarian cancer. Most are diagnosed in the early stages of the disease. The surgery may be less aggressive and chemotherapy is usually not necessary. There are five varieties: borderline serous, mucinous, clear cell, endometrioid and borderline Brenner tumour.  

Invasive ovarian cancer. There are many types or varieties of invasive ovarian cancer, but the most common are grouped into four categories depending on the type of cell they originate from:  

  • Epithelial carcinoma. These originate in the thin layer of tissue that covers the outside of the ovaries; they make up 85-90% of ovarian cancers. The main types of epithelial tumours include serous (the most common), endometrioid, clear cell, and mucinous tumours, but there are also others that are rarer. There are differences in the ways these cancers behave and which treatments work best. They are subdivided into two types, high grade (the most common) and low grade.  
  • Malignant germ cell tumours. These are less frequent and develop in the ovary-producing ovarian cells. They usually appear in women between the ages of 10 and 29. The varieties are: dysgerminomas, immature teratomas, endodermal sinus and yolk sac tumours, and embryonal carcinomas. 
  • Malignant stromal tumours. This rare form of ovarian cancer develops in the hormone-producing ovarian cells. More than 90% of these tumours are known as granulosa cell tumours, and there are two types: adult and juvenile. Granulosa cell tumours can secrete oestrogen, causing unusual vaginal bleeding.   

Metastatic tumours. Rare (5-10% of ovarian cancers). In this case, the primary tumour does not originate in the fallopian tube/ovary, but in a distant organ. It may originate in another genital organ (such as the endometrium), in the digestive system (particularly the colon and stomach), or in the breasts. Sometimes the ovarian metastasis is detected before the primary tumour.  

How many people does it affect?

In the United States, ovarian cancer is diagnosed in more than 20,000 women, with about 15,000 deaths per year. Half of these women are over 60. The vast majority are high-grade serous tumours and most are diagnosed when the disease is already at an advanced stage.  

Ovarian cancer, including those that originate in the cells of the ovary, fallopian tubes, and peritoneum, is the fifth most common cause of cancer-related death in women in the United States.  

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Substantiated information by:

Lydia Gaba

Published: 3 July 2020
Updated: 3 July 2020

The donations that can be done through this webpage are exclusively for the benefit of Hospital Clínic of Barcelona through Fundació Clínic per a la Recerca Biomèdica and not for BBVA Foundation, entity that collaborates with the project of PortalClínic.


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