What is the recommended workup and treatment approach for a patient suspected of having ovarian cancer?

Recommended Workup and Treatment Approach for Suspected Ovarian Cancer

The standard workup for patients suspected of having ovarian cancer should include detailed history and clinical examination, serum CA-125, transabdominal and transvaginal ultrasound, CT of thorax/abdomen/pelvis, and pathological examination of adequate tumor samples from either diagnostic biopsy or surgical specimen. 1

Initial Diagnostic Workup

Clinical Presentation

• Common symptoms: abdominal/pelvic pain, constipation, diarrhea, urinary frequency, vaginal bleeding, abdominal distension, and fatigue
• Advanced disease symptoms: bloating, nausea, anorexia, dyspepsia, early satiety, and respiratory symptoms (if pleural effusions present) 1

Laboratory Tests

• Serum CA-125 (elevated in ~85% of advanced disease but only ~50% of early-stage cases) 1
• For suspected mucinous carcinoma: Serum CEA and CA 19-9 (to distinguish primary mucinous ovarian tumors from gastrointestinal metastases) 1
• Consider endoscopy if CA-125/CEA ratio is ≤25 1
• For young patients with suspected germ cell tumors: serum hCG, AFP, and LDH 1
• Inhibin levels for suspected granulosa cell tumors 1

Imaging Studies

• Transvaginal and transabdominal ultrasound (initial imaging of choice) 1
• CT scan of thorax, abdomen, and pelvis (to assess for metastases and aid surgical planning) 1
• Consider MRI for indeterminate lesions 1
• FDG-PET/CT scan may be useful for selected cases with indeterminate lesions 1

Definitive Diagnosis

• Pathological examination by an expert pathologist of tumor samples from either:
  • Diagnostic biopsy (if surgery not feasible)
  • Surgical specimen (preferred) 1
• Cytological assessment of pleural effusion if present 1

Staging and Risk Assessment

• FIGO staging remains the most powerful indicator of prognosis 1
• Preoperative assessment with cross-sectional imaging is essential as it guides surgery 1
• Histological diagnosis should be obtained whenever possible; avoid relying solely on cytological diagnosis 1

Treatment Approach

Early-Stage Disease (FIGO I and IIA)

1. Surgery:

   • Total abdominal hysterectomy
   • Bilateral salpingo-oophorectomy with omentectomy
   • Staging biopsies
   • Pelvic/para-aortic lymph node sampling 1
   • For younger patients with localized, unilateral tumors wanting to preserve fertility: consider unilateral salpingo-oophorectomy 1

2. Adjuvant Chemotherapy:

   • FIGO stage Ia/b, well-differentiated, non-clear cell: surgery alone is adequate 1
   • FIGO stage Ia/b poorly differentiated, clear cell histology, and all grades of FIGO stage Ic and IIA: adjuvant chemotherapy recommended 1
   • Standard regimen: carboplatin AUC 5-7 1, 2

Advanced Disease (FIGO IIB-IIIC)

1. Surgery:

   • Maximal cytoreductive surgery with the goal of no residual disease 1
   • If initial maximal cytoreduction not performed, consider interval debulking surgery after 3 cycles of chemotherapy in responding patients 1

2. Chemotherapy:

   • Standard regimen: carboplatin AUC 5-7.5 plus paclitaxel 175 mg/m² over 3 hours every 3 weeks for 6 cycles 1, 3, 2
   • Alternative regimen: paclitaxel 135 mg/m² over 24 hours followed by cisplatin 75 mg/m² 3

Stage IV Disease

• Maximal surgical cytoreduction provides survival advantage 1
• For patients not suitable for surgery: confirm diagnosis by biopsy and administer chemotherapy as for stage IIB-IIIC 1
• Young patients with good performance status, pleural effusion as only site of disease outside abdominal cavity, small volume metastases, and no major organ dysfunction should be considered for surgery 1

Response Evaluation and Follow-up

• CA-125 levels correlate with tumor response and survival during chemotherapy 1
• Measure serum CA-125 prior to each cycle of chemotherapy 1
• Repeat CT scan after cycle 6 for patients with abnormal baseline scans 1
• Earlier CT scan indicated if evidence of non-responding disease 1

Important Considerations

• Despite high initial response rates (up to 80%), approximately 75% of patients with advanced-stage disease relapse within 2 years 4, 5
• 5-year survival rates vary significantly by stage: 70-95% for early-stage disease vs. 10-40% for advanced-stage disease 4
• Patients with BRCA-related gene variants have better outcomes with PARP inhibitor treatment (5-year survival rate of approximately 70%) 4
• No evidence supports routine screening for ovarian cancer in the general population 1

Pitfalls to Avoid

1. Misinterpreting CA-125 levels: CA-125 is not specific to ovarian cancer and may be elevated in non-gynecological malignancies and benign conditions (e.g., endometriosis, ovarian cysts) 1, 6

2. Inadequate surgical staging: Comprehensive surgical staging is critical for determining prognosis and guiding adjuvant therapy decisions 1

3. Relying solely on FNA for diagnosis: When possible, avoid fine-needle aspiration in patients with presumed early-stage disease to prevent rupturing the cyst and spilling malignant cells into the peritoneal cavity 1

4. Delaying treatment: Given the high mortality rate of ovarian cancer, prompt referral to a gynecologic oncologist is essential when ovarian cancer is suspected 7