Approximately 20% of women will develop a pelvic mass at some time in their lives. Pelvic masses present difficulties in both diagnosis and management. When a patient presents with a pelvic mass, the specialist needs to first determine if the mass is gynecologic in origin and then determine whether it is benign or malignant.

A complex mass means that it contains both cystic and solid component and can arise from gynaecological organs or non- gynaecological organs. We will focus on the gynaecological perspective. It can be benign (non-cancerous), borderline (atypical cells but not cancer) or cancerous.

While benign ovarian masses are harmless, ovarian cancers need to be recognized so that we can treat them accordingly. There is no robust tool available to distinguish between benign and cancerous masses.

We use the patient’s age, features on medical imaging (ultrasound/CT scan/MRI) and tumour markers (blood tests) to estimate the risk of cancer.

  • In patients with a very low risk of cancer, conservative management with follow up imaging can be offered especially if there is no symptom
  • Patients who develop symptoms (pain) but otherwise have a low risk of malignancy, surgery will be offered
  • Patients with a moderate or high risk of malignancy are offered expedited surgery and those patients may benefit from surgery with a gynaecological oncologist. Surgery with a gynaecological oncologist will save the patient an unnecessary second surgical procedure in case a malignancy is found

Patients with a personal history of breast cancer or patients with a family history of breast, ovarian, pancreatic and other cancers may carry genes predisposing them to ovarian cancer. In such circumstances a consultation with a gynaecological oncologist who understand cancer genetics is appropriate

Premenopausal women

Pelvic masses can arise from the ovary but also from other structures in the pelvis such as the fallopian tube, the uterus, the bowel, appendix, or the kidney.

  • Functional cysts including polycystic ovary syndrome
  • Pregnancy-related (ectopic pregnancy)
  • Inflammation/infection (Pelvic inflammatory disease, tubo-ovarian abscess)
  • Endometriosis (endometrioma)
  • Fibroids (arising from the uterus)
  • Ovarian cancer
  • Cancers arising from somewhere else but spread to the ovary

Pelvic masses and ovarian cysts require surgical exploration if they are either considered as suspicious or if they cause symptoms.

Postmenopausal women
The likelihood that a pelvic mass is cancerous increases with age. All suspicious ovarian masses in menopausal women should be referred to a gynaecological oncologist. Advanced age is the biggest single risk factor. Imaging and tumour markers (blood tests) may point to the high probability of ovarian cancer but some types of ovarian cancer are extremely difficult to diagnose prior to surgery