Ovarian Cancer: All you need to know

India

healthysoch

New Delhi, March 17, 2020 :

Among the gynaecological cancers, ovarian cancer is the most common cause of cancer death. An estimated 200,000 women around the world develop ovarian cancer every year, and it claims about 100,000 lives each year. Also, one in every 70 women has the lifetime risk of developing epithelial ovarian cancer. As per the data by the Indian Council of Medical Research (ICMR), in India, Ovarian cancer ranks as the 3^rd most common cancer in women after cancers of breast and cervix.  In many cases, breasts and ovarian cancers are found to have occurred metachronously due to inherited genetic mutations, and it is called Hereditary Breast and Ovarian Cancer syndrome.

Ovarian cancer is of many types.  The most common type arises from ovarian surface lining and occurs in the post-menopausal women.  There are two ovaries in the female reproductive system, one on each side of the uterus. Ovarian cancer can be successfully treated if detected in its early stage, when the cancer is still confined to the ovary.  Patient with ovarian cancer in its early stage shows minimal to no symptoms at all.  With the result, the patient does not seek any medical advice.  This is the main reason behind most cases being diagnosed at the advanced stage.

Although, a number of risk factors contributing to ovarian cancer e.g. post-menopausal status genetic predisposition, Hormonal replacement therapy, overweight & smoking have been identified lately, the exact cause of ovarian cancer still remains elusive.

Ovarian Cancer Diagnostics

• Screening

1. Screening for general population : Unlike cervical and breast cancer screening techniques, there is no standardised screening method available for early detection of ovarian cancer.  STIC which is the epithelial precursor lesion can be detected early only by a laparoscopic biopsy which is not feasible in every case.  Hence screening will not be of much help in diagnosing early precancerous states.
2. Screening for high risk women : Transvaginal USG however may be of some use in post-menopausal women as a practical tool in detecting early ovarian cancers.  Serial and annual USG evaluation will be more helpful rather than a single test.

• Genetic Risk Assessment and Counselling : The BRCA gene has a significant role in the disease process of hereditary ovarian cancer.  Many women may have genetic alteration of BRCA gene.  Genetic screening for BRCA oncogene hence can help in identifying at risk woman who can later develop ovarian cancer in the future.  Close monitoring of these women can facilitate early identification of the disease.  It must be pointed out here that presence of altered BRCA gene may not always lead to the development of cancer.
• Diagnostic tests for ovarian cancer

1. Biomarkers : CA125 is the most commonly tested biomarker for ovarian cancer.  Stage of the disease at the time of presentation plays a vital role in evaluating the diagnostic utility of this test. CA-125 is not generally considered as a good enough tumour marker for screening purpose or a diagnostic marker to discriminate benign tumours from the malignant ounces in premenopausal women.  It is regarded as a more specific test more specific to detect ovarian cancer in post-menopausal women.

In comparison to a CA125 test alone, the combination of human epididymis secretory protein 4 (HE4) is found recently to be more competent (sensitive) in the detection of ovarian cancer.

Transvaginal USG and combination of tumour marker may be offered to screen women who have a high risk of ovarian cancer due to an inherited genetic syndrome such as Lynch syndrome BRCA gene mutation or strong history of breast or ovarian cancer.

Imaging (Radiology) : In full blown cases of carcinoma ovary, the extent (stage) of the disease and the feasibility of surgical resection is evaluated by a computed tomography (CT) scan of the abdomen and pelvis with oral and intravenous contrast, and chest imaging (CT preferred).  As per the clinical indications, other tests including Positron Emission Tomography (PET) CT scan or magnetic resonance imaging (MRI) can also be performed for determining the stage of disease.

Biopsy :The most reliable type of tests to know if a certain growth is cancer is to cut a small piece from cancerous tissue and get it examined in the histopathology lab. This test is called a biopsy. In case of ovarian cancer, the procedure involves a surgical removal of the tumour. The tumour tissue is processed and slide is prepared which is viewed under a microscope by histopathologist.  On microscopic examination, a final diagnosis of ovarian cancer and its type is rendered by histopathologist which helps in determining the treatment regime.

Ascitic fluid cytology : Sometimes in ovarian cancer, abdominal (peritoneal) cavity is filled with fluid which can be removed and sent to pathology laboratory.  Pathologist can detect the cancer cells floating in the fluid.

Treatment  : In early stages when the tumour is operable, surgical resection of the tumour is the treatment of choice.  However in advanced cases where the tumour has spread, chemotherapy is the preferred treatment modality.

TO CONCLUDE

Ovarian cancer is common in elderly women and is associated with higher mortality rate.  Early detection and prompt diagnosis can help in curing patients and reducing morbidity and mortality.  Post-menopausal obese women with positive family history should consult a specialist (Gynaecologic Oncologist) for early detection of ovarian cancer.

Author : Dr. Shubhada Kane, Head- COE Histopathology, SRL Diagnostics.