Ovarian cancer

What is this ?

The ovaries are two glands (organs that produce hormones) located on either side of the uterus and connected to the uterine cavity via the fallopian tubes. They are part of the female reproductive system.

Ovarian cancer is most often a tumor that develops from what is called the ovarian epithelium, which is the outer layer of tissue surrounding the gland itself.

With an estimated 314,000 new cases worldwide in 2020 (source: GLOBOCAN 2020), it is the 8th most common cancer in women globally. The disease primarily affects women over the age of 65, although earlier-onset forms are possible, particularly in cases of genetic predisposition.

Causes and risk factors

Throughout a woman's reproductive years (typically between ages 15-49), the ovaries produce a mature ovocyte (egg) each month. This egg then migrates to the uterine cavity to potentially be fertilized—a process known as ovulation.

Ovulation is accompanied by the secretion of inflammatory factors, hormones, and repeated healing of the ovarian surface, all of which may individually contribute to the development of the disease.

A higher number of ovulations is therefore a risk factor, which includes :

• No pregnancies
• Early onset of menstruation
• Late menopause
• Age (> 65 years)
• Overweight or obesity

Conversely, taking oral contraceptives is considered a protective factor.

The main risk factor, however, is the presence of an inherited genetic mutation. These predisposition syndromes account for 15-20% of high-grade ovarian cancers. They mainly involve abnormalities in the BRCA1 or BRCA2 genes, or more rarely, Lynch syndrome.

If you have a high-grade epithelial tumor, your doctor will systematically recommend testing for these genetic anomalies.

Screening

Currently, there is no validated test for the early detection of ovarian cancer. The role of pelvic ultrasound or the Ca-125 marker has not yet been proven.

Symptoms

In most cases, the disease develops in a "stretchable" hollow space, meaning that symptoms only appear later when the cancer is already relatively advanced.

The most common symptoms include :

• A feeling of abdominal heaviness
• Unexplained weight gain
• Increase in abdominal girth

There may also be functional signs such as :

• Altered bowel movements
• Urinary issues

General symptoms may also be present, such as :

• Fatigue
• Loss of appetite

None of these signs are 100% specific, but their intensity and/or persistence over time should prompt a medical consultation.

Diagnosis

Most often, symptoms lead to an abdominal-pelvic and transvaginal ultrasound. If a malignant ovarian lesion is suspected, a radiologist should perform a lumbar-pelvic MRI.

Definitive diagnosis relies on obtaining histological samples, meaning a tissue fragment from the tumor, typically via laparoscopy. This procedure is performed in the operating room under anesthesia. The healthcare professional makes three small incisions for the various instruments (one under the navel and one on each side) to avoid large scars. This examination allows direct visual exploration of the entire abdominal cavity with a camera, visualization of the ovarian lesion, and sampling of any suspicious areas.

It usually takes about a week to receive the complete biopsy results.

Treatments

The treatment approach varies depending on the stage of the disease.

For localized tumors, surgery is the standard treatment. If the disease is more widespread, systemic medical treatment (which affects the entire body) involving chemotherapy, possibly followed by targeted therapy, will accompany surgery.

If the tumor's spread is limited, surgery is performed first, followed by systemic treatment.

Finally, if the tumor's spread prevents immediate resection, 3 to 4 cycles of chemotherapy are administered, followed by an "interval" surgery if the chemotherapy response is satisfactory.

Chemotherapy is then resumed, combined with anti-angiogenic targeted therapy delivered by infusion, which is continued as maintenance therapy for 15 months. In the case of a BRCA mutation, a specific oral targeted therapy replaces the anti-angiogenic targeted therapy for a minimum of 2 years.

If surgery remains impossible after the initial chemotherapy cycles, the patient will continue with chemotherapy.