Ovarian cancer originates in the ovaries and is primarily classified into three types: epithelial tumours, stromal tumours, and germ cell tumours. Epithelial ovarian cancer (EOC) is the most common, accounting for about 90% of cases. The pathogenesis involves genetic mutations in BRCA1 and BRCA2, as well as other oncogenes and tumour suppressor genes.
About
- Leading cause of death and 8% of cancers in women
- Incidence falling with use of Contraception
Aetiology
- Family history of ovarian or breast cancer
- Inherited gene mutations (e.g., BRCA1, BRCA2, Lynch syndrome)
- Age (most common in postmenopausal women)
- Reproductive history and infertility
- Hormone replacement therapy
Clinical
- Bloating/abdominal distension, urinary incontinence, urgency
- Early satiety, pelvic and abdominal pain
- Unexplained weight loss, fatigue or changes in bowel habit.
- Diagnosis is often delayed and late
Differentials
- Early symptoms misdiagnosed as irritable bowel syndrome which is rare in onset in those over 50
Investigations
- Bloods: FBC/ESR: Anaemia, LFTS, AFP and B HCG: In women under 40 with suspected ovarian cancer, measure levels of alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin (beta-hCG) as well as serum CA125, to identify women who may not have epithelial ovarian cancer.
- Pelvic Examination: Often the first step in evaluating symptoms.
- Transvaginal Ultrasound: Used to visualize ovarian masses.
- CA-125 Blood Test: Elevated in many cases of epithelial ovarian cancer. Elevated CA-125 in some but not all (false positive in menstruation). If serum CA125 is 35 IU/ml or greater, arrange an ultrasound scan of the abdomen and pelvis. For any woman who has normal serum CA125 (less than 35 IU/ml), or CA125 of 35 IU/ml or greater but for a normal ultrasound: assess her carefully for other clinical causes of her symptoms and investigate if appropriate if no other clinical cause is apparent, advise her to return to her GP if her symptoms become more frequent and/or persistent.
- CT/MRI Scans: For detailed imaging and assessment of metastasis.
- Biopsy: Definitive diagnosis through histopathological examination. If offering cytotoxic chemotherapy to women with suspected advanced ovarian cancer, first obtain a confirmed tissue diagnosis by histology (or by cytology if histology is not appropriate) in all but exceptional cases.
Staging FIGO (International Federation of Gynaecology and Obstetrics) system:
Stage |
Description |
Stage I |
Cancer confined to the ovaries. |
Stage II |
Cancer has spread to the pelvis. |
Stage III |
Cancer has spread to the abdominal cavity. |
Stage IV |
Distant metastasis is present. |
Management
- Surgery: Consider hysterectomy, bilateral salpingo-oophorectomy, and debulking surgery.
- Chemotherapy: Platinum-based chemotherapy (e.g., carboplatin, cisplatin) is standard. Platinum based chemotherapy is widely used to treat ovarian cancer. Most commonly carboplatin is used, and sometimes cisplatin or paclitaxel (also known as Taxol). It is standard practise to give chemotherapy once every three weeks for six cycles. However, giving smaller weekly doses over an 18-week period is becoming more common, as there appears to be some clinical benefit and increased tolerance.
- Targeted Therapy: Includes PARP inhibitors for patients with BRCA mutations.
- Radiation Therapy: Less commonly used but may be considered in specific cases.
- Immunotherapy: Emerging treatment modality under investigation.