OVERVIEW
Ovarian cancer is a malignancy that arises from the ovaries which are part of the female reproductive system. The ovaries are paired structures present on either side of the uterus. They are the female gonads and produce eggs as well as the female hormones estrogen and progesterone

Ovarian cancer is the seventh leading cause of cancer women globally. It has the lowest survival rate among all gynecologic cancers, mainly due to lack of awareness of symptoms and advanced stage at the time of diagnosis. Approximately a quarter of a million women globally are diagnosed every year accounting for nearly 140,000 deaths each year

TYPES OF OVARIAN CANCER
Ovarian cancer is classified into various types depending on which cell in the ovaries it arises from. The types of ovarian cancer are the following

 Epithelial tumors – arise from the surface epithelium of the ovary (90%). Seen in women over the age of 50 years
 Stromal tumors – Arise from the ovarian stromal cells that includes hormone producing cells. These may be diagnosed earlier than other ovarian cancer types and account for about 7% of ovarian cancers
 Germ cell tumors – These are rare tumors that arise in the egg producing cells of the ovary and often seen in younger women
 Metastatic tumors (secondary) - May arise from the breast, uterus or cervix, gastrointestinal tract, haemopoietic system



CAUSES AND RISK FACTORS OF OVARIAN CANCER
It is not clear why ovarian cancers occur. However several factors have been identified that can increase the risk of ovarian cancer. These include

 Increasing age – Over 50-60 years
 Lifestyle factors – Smoking, sedentary lifestyle, obesity, asbestos exposure
 Hormonal factors – Infertility, use of fertility drugs, prolonged HRT, early menarche and late menopause
 Medical history – History of breast, ovarian or bowel cancer, history of endometriosis
 Genetic factors – Family history of ovarian cancer, occurrence of BRCA-1 and BRCA-2 genes

SIGNS AND SYMPTOMS OF OVARIAN CANCER
Unfortunately a majority of patients present in the advanced stage (III or IV) of disease. The clinical features include

 Vague abdominal symptoms such as abdominal distension, discomfort, indigestion
 Urinary frequency
 Tiredness, weight loss, loss of appetite
 Abnormal uterine bleeding
 Abdominal mass on palpation
 Ascites (fluid in peritoneal cavity)
 Pleural effusion (in a third of patients with ascites)

DIFFERENTIAL DIAGNOSIS
Other causes of abdominal mass and symptoms and/or abnormal uterine bleeding must be considered clinically. These include

 Benign ovarian cyst
 Uterine fibroid
 Pelvic malignancy – uterus, cervix, rectum or bladder cancer
 Endometriosis
 Pelvic inflammatory disease
 Diverticulitis

DIAGNOSIS OF OVARIAN CANCER
● Physical examination – A pelvic examination may be performed by inserting a gloved finger into the vagina and pressing the lower abdomen with the other hand to feel the pelvic organs. Based on clinical suspicion, further blood tests and imaging tests may be advised

● Blood tests – A blood test to measure CA-125, which is a protein that can be increased in ovarian cancer. It is not diagnostic of ovarian cancer and is raised in other conditions as well. In the presence of ovarian cancer, measurement of CA-125 levels can be used to determine response to treatment

● Imaging tests – Imaging tests such as abdominal and pelvic ultrasound, CT or MRI scan of the abdomen and pelvis will give more information about the abdominal and pelvic organs

STAGING AND GRADING
The clinical stage of a cancer tells whether the cancer is confined to the organ or has spread. There are 4 stages of ovarian cancer

▪ Stage 1 – Cancer limited to one or both of the ovaries
▪ Stage 2 – Has spread outside the ovaries but contained within the pelvis
▪ Stage 3 – Has spread outside the pelvis to the lining of the abdomen and bowel
▪ Stage 4 – Has spread to distant sites such as liver, spleen, lungs

Stage I and II cancers have a better outcome than stage III or IV cancers

Grading
Cancer cells are graded according to their appearance under a microscope. These include
▪ Low grade (almost normal appearance)
▪ Moderate grade (slightly more abnormal than low grade) or
▪ High grade (highly abnormal appearance)

In general low grade tumors are slow growing and have a better outcome than high grade tumors which are aggressive

COMPLICATIONS OF OVARIAN CANCER
Tumor torsion, rupture or bleeding
Advanced disease – malnutrition, cachexia, bowel obstruction, ascites, pleural effusion, infections

TREATMENT OF OVARIAN CANCER
Treatment depends on the stage of disease and grade of tumor cells. The main modalities of treatment include surgery and chemotherapy.

Surgery
Stage I – Bilateral salpingo-oopherectomy
Stage II – Total abdominal hysterectomy with bilateral salpingo-oopherectomy including omentectomy and lymph node clearance
Stage III/IV – Extensive debulking surgery

Chemotherapy
Chemotherapy is often used after surgery to kill any residual cancer cells. It can also be used before surgery. Chemotherapy involves administering drugs either intravenously or orally. It consists of platinum based therapies

Targeted therapy
Targeted therapy is usually reserved for ovarian cancer that returns after initial treatment or cancer that resists other treatments. Examples include Bevacizumab (VEGF inhibitor) and Olaparib ( PARP inhibitors)

Palliative and Supportive Care
While undergoing intensive surgery and chemotherapy supportive care to reduce pain and other symptoms and make the patient comfortable. It is also indicated in large inoperable tumors to keep the patient comfortable and free from pain