About ovarian cancer

About ovarian cancer

Ovarian cancer occurs when the normal division and growth of ovarian or Fallopian tube cells is disrupted, leading to uncontrolled cell growth. These abnormal cells usually also spread to tissues or organs throughout the peritoneal cavity.

There are four main types of ovarian cancer, classified by the type of ovarian cells affected:

  1. Epithelial ovarian cancers comprise 90% of ovarian cancers. Unfortunately, they also tend to be the most aggressive.
  2. Borderline cancers are a less aggressive and less common type of epithelial ovarian cancer.
  3. Germ cell ovarian cancers arise from the eggs within the ovary. This type of cancer is uncommon, and tends to occur in women under 30 years of age. It generally responds well to treatment, and young women may still be able to have children afterwards if only one ovary is affected.
  4. Sex-cord stromal ovarian cancers originate from the tissue that releases female hormones. These are uncommon and can occur at any age.
  • Risks
  • Symptoms & diagnosis
  • Treatment

The risk for ovarian cancer increases with age and is most common in women over 50, or who have gone through menopause. Other risk factors include reaching puberty before 12, menopause after 50, not having had children or having them over the age of 30, endometriosis (a common gynaecological condition), or being overweight. The use of oral contraceptives, however, can reduce the risk of developing ovarian cancer by almost half.

Recent research has shown that the major risk genes, BRCA1 and BRCA2, are primarily associated with the most common high-grade serous ovarian cancer (HGSC) type of ovarian cancer, as well as with breast cancer. Not all women with these mutations will develop ovarian cancer, but the chances are high. For women with a BRCA1 or BRCA2 mutation who have not yet developed ovarian cancer, risk-reducing surgery to remove the ovaries and fallopian tubes can reduce the chance of developing ovarian cancer by 80–90%.

Ovarian cancer can be difficult to diagnose or detect because the ovaries are located deep in the abdomen, where tumours can grow to a substantial size without obvious symptoms. When symptoms do develop, they are ones that many women experience from time to time:

  • Abdominal or pelvic pain
  • Increased abdominal size
  • Persistent abdominal bloating
  • Constant or urgent urination
  • Feeling full after eating

These symptoms are very common and this can make it difficult to be aware of the development of ovarian cancer.

Ovarian cancer is rarely diagnosed and treated in the early stages and around 75% of patients present with advanced cancer at diagnosis. Of these women, only 35–40% are likely to survive for five years, compared with around 90% for women with breast cancer.

Ovarian cancer is typically diagnosed by a combination of imaging, such as CT scan or ultrasound, biopsy, and blood tests. Often, a definite diagnosis and understanding of the type and extent of the cancer requires surgery, which is also aimed at removing as much of the cancer as possible.

Following surgery, women receive chemotherapy, typically with carboplatin and a type of drug called a taxane. These kill cancer cells in different ways and in combination are more effective than either alone. While some women will be cured with this combined treatment, over time many cancers can recur and become resistant to chemotherapy.

The radical shift in understanding of the origins and types of ovarian cancer is resulting in the development of more targeted chemotherapy and greater use of personalised therapies where treatment is matched to the underlying cellular type of the person’s cancer. This new focus on genetics and the subtypes of ovarian cancer has led to clinical trials for new treatments and new combinations of treatments.