Ovarian Cancer

While the term ‘ovarian cancer’ describes cancers that appear to arise in the ovary, we now know that many of these cancers start in the fallopian tubes. The fallopian tubes carry eggs from the ovary to the uterus or womb. Often, cancer has spread beyond the ovaries by the time it is detected. Cancers that have spread prior to diagnosis are harder to treat and often come back after treatment. This means that survival rates for ovarian cancer are worse than for many other cancers. Fewer than five in 10 women diagnosed with ovarian cancer will still be alive in five years. Even though ovarian cancer is the tenth most common cancer in Australian women, it is the sixth most common cause of cancer death.

There is currently no screening test for ovarian cancer. Reducing obesity and smoking rates will prevent a small proportion of cases, but we do not have a simple method to prevent women from developing ovarian cancer. This makes early detection critical. However, this is challenging because the symptoms of ovarian cancer can be vague and easily confused with other less serious conditions. Common symptoms include:

• abdominal bloating: feeling consistently bloated, or an increase in the size of your abdomen
• pelvic or abdominal pain: persistent pain in the pelvic or abdominal region
• difficulty eating: loss of appetite or feeling full quickly after eating
• urinary issues: changes in urinary patterns, such as increased urgency or frequency
• sudden and unexplained weight loss without changes in diet or physical activity
• fatigue: unexplained and persistent fatigue.

Ovarian cancer can occur at any age but is most common in women over 60.

There’s a greatly increased risk of developing ovarian cancer for women who have one of the breast cancer or BRCA genes. This puts them at a higher risk of developing both breast and ovarian cancers. Thankfully, these mutations are rare and only account for around one-tenth of all ovarian cancers.

Women with endometriosis are also more likely to develop ovarian cancer.

In contrast, women who are pregnant, breastfeeding, or using the contraceptive pill have a lower risk of developing epithelial ovarian cancer.

Before 1950, there were only two options to treat ovarian cancer – surgery and radiotherapy. Treatments have advanced since then, but their efficacy depends on several factors. These include the stage of the cancer, the patient’s overall health, and their preferences.

Treatment options may include:

• Surgery: the primary treatment for ovarian cancer involves surgically removing the tumour and, if necessary, the affected ovaries and fallopian tubes. In advanced cases, additional organs may also need to be removed;
• Chemotherapy: often used after surgery to kill any remaining cancer cells and reduce the risk of recurrence. It may also be used before surgery to shrink the tumour;
• Targeted therapy: this type of treatment focuses on specific molecules involved in cancer growth and progression;
• Immunotherapy: stimulating the body’s immune system to recognise and attack cancer cells;
• Radiation therapy: while less common, radiation therapy may be used in certain cases, particularly for advanced cancer that has spread to other areas.

Ovarian cancer is not a single disease. There are many types of ovarian cancer, all of which respond differently to treatment and have different risk factors.

Within the main group of ‘epithelial’ ovarian cancers, there are subtypes with distinctive molecular changes, which affect how the cancers respond to drugs.

One type of ovarian cancer is more common in women who smoke. Others seem to be more common in women who are overweight or obese.

These complexities make ovarian cancer challenging to study. We need to look at each type separately and develop different therapeutic strategies to target the more aggressive forms of ovarian cancers.