Laboratory Workup for a Potential Pelvic Mass
For a potential pelvic mass, the recommended laboratory workup should include serum CA-125, complete blood count, liver and renal function tests, and specific tumor markers based on patient age and suspected histology. 1
Initial Laboratory Evaluation
- Serum CA-125 measurement is recommended as part of the initial evaluation of a pelvic mass to help differentiate between benign and malignant processes 1, 2
- Complete blood count (CBC) should be performed to assess for anemia or other hematologic abnormalities that may be associated with malignancy 1
- Comprehensive metabolic panel including liver function tests (LFTs) and renal function tests should be obtained to evaluate organ function and establish baseline values 1
- Lactate dehydrogenase (LDH) measurement is recommended as it can be elevated in certain types of ovarian malignancies, particularly germ cell tumors 1
Age-Specific Tumor Markers
- For women younger than 35 years with a pelvic mass, alpha-fetoprotein (AFP) levels should be measured to assess for germ cell tumors and to rule out pregnancy 1
- Human chorionic gonadotropin (hCG) should be measured in young patients to rule out pregnancy and evaluate for certain germ cell tumors 1
- Inhibin levels should be considered, particularly if a granulosa cell tumor is suspected, as it is a useful marker for this disease 1
Additional Testing Based on Suspected Histology
- For suspected mucinous histology, carcinoembryonic antigen (CEA) should be measured and a gastrointestinal tract evaluation should be performed to determine whether the mass represents a primary ovarian tumor or metastasis from a gastrointestinal primary 1
- In cases of suspected gonadoblastomas, a preoperative karyotype should be obtained, especially in pre-menarche girls, due to the propensity of these tumors to arise in dysgenetic gonads 1
Imaging Correlation
- Laboratory results should be interpreted in conjunction with imaging findings from transvaginal/transabdominal ultrasound and/or abdominal/pelvic CT/MRI 2, 3
- For indeterminate masses on ultrasound, MRI may provide additional characterization and should be considered before finalizing the laboratory workup plan 4, 3
Special Considerations
- For sex cord-stromal tumors, which may produce hormones, additional endocrine evaluation may be necessary 1
- In patients with suspected non-epithelial ovarian cancers, a more extensive tumor marker panel (CA-125, inhibin, beta-hCG, AFP, and CEA) should be considered 1
- For patients with suspected malignancy who are not surgical candidates, fine-needle aspiration may be necessary, though this should be avoided in patients with presumed early-stage disease to prevent rupturing the cyst and spilling malignant cells 1
Common Pitfalls to Avoid
- Relying solely on CA-125 for diagnosis, as it can be elevated in many benign conditions and may not be elevated in early-stage ovarian cancer 1
- Failing to consider age-appropriate tumor markers, which may lead to missed diagnoses, particularly in younger patients 1
- Not performing a gastrointestinal evaluation in patients with mucinous histology, which could result in misdiagnosis of metastatic disease as primary ovarian cancer 1