Ovarian cancer is the leading cause of death from gynecological cancers in the UK and USA. It is the 5th most common cause of cancer deaths in women (after lung, breast, colorectal and pancreatic cancers). Up to 20,000 new cases are diagnosed yearly in the US. The peak incidence is in women aged 75 – 84 years, but it can occur in younger women, and even (rarely) in prepubescent girls too.
The ovaries consist of different cell types, performing different functions. Any of these cells can develop into cancer, but 90% arise from the epithelial (outermost) cells. Ovarian cancers are classified based on the cluster of cells they originate from:
- Sex cord-stromal
- Germ cells
Different subclasses have been described and each has similar features but different growth behavior and response to treatment.
Like most cancers, direct causal factors are largely unknown, but various risk factors have been identified:
- Nulliparity (no previous viable pregnancy)
- Early menarche (age at onset of menstruation <11 years)
- Late menopause (age at cessation of menstruation >52 years)
- Family history of ovarian, breast or colorectal (bowel) cancers
- Family history of genetic mutations ( BRCA1, BRCA2, and HNPCC)
- Previous history of ovarian, breast, endometrial and colorectal cancers (treated)
SCREENING FOR OVARIAN CANCER
Not routinely done unless one has strong risk factors.
SIGNS AND SYMPTOMS
Ovarian cancer is a great mimicker as it doesn’t show any specific sign until an advanced stage as been reached. Early symptoms are no different from those attributable to other common diseases. These are:
- Abdominal pain
- Abdominal distension and bloating
- Loss of appetite
- Constipation or diarrhea (or alternation of both)
- Abnormal menses or vaginal bleeding
Late Symptoms include;
- Abdominal/pelvic mass – detected by palpation and confirmed by radiological tests
- Significant weight loss
- Difficulty in passing urine
- Significant abdominal distension (ascites or solid mass)
- Generalized body swelling (edema or anasarca)
- Signs of spread to distant organs – uterus and tubes, urinary tract, bowel, stomach, lymph nodes, etc.
After taking a full history and physical examination, specific tests must be done to confirm the diagnosis, determine the extent of the disease and work up for definitive treatment.
- Full blood count
- Kidney function test
- Liver function test
- Tumor markers – CA125, CEA, CA19.9, etc.
- Imaging: ultrasound, CT scan, MRI, chest x-ray, etc
- SURGERY: This is both diagnostic and therapeutic. In early stages, the ovaries, uterus, tubes and adjacent lymph nodes will be removed at once. In advanced stages, initial surgery is done to “stage” cancer (to know what stage it is). Subsequent operations may be needed depending on the result of the first surgery and response or recurrence.
- CHEMOTHERAPY: The different combination of anti-cancer drugs are available depending on the cell types involved. The platinum-based therapy is given in up to 6 cycles every 3 weeks. Side effects of the drugs include severe vomiting, hair loss, kidney damage, diarrhea etc. These can also be managed and ameliorated.
- NOVEL AGENTS: New drugs are being investigated through clinical trials. These include antibodies against cancer-promoting factors in the body (VEGF, EGFR and TKI’s)
- SUPPORTIVE TREATMENT: These are palliative measures put in place to alleviate the excruciating pain and suffering associated with advanced ovarian cancer. Such as drainage of ascites, painkillers (strong opioids usually, morphine), emotional support, hospice care, etc.
FOLLOW UP IS OFTEN CONTINUED LIFELONG.
5-year survival rate ranges from 90% to less than 20% depending on the stage of cancer before treatment is commenced.
It is said that the only way to not have cancer is not to be born. Ovarian cancer can not be predicted 100% but individuals with strong risk factors can be followed closely so as to detect the disease early. They can also opt for prophylactic oophorectomy (removal of the ovaries) after completing their reproductive career (cf. Angelina Jolie). For younger women, eggs can be harvested, frozen and used for IVF when they’re ready to get pregnant later.
General healthy lifestyle helps to prevent cancer among other things – healthy diet, regular exercise, quitting alcohol and smoking, etc.