Prognosis of Ovarian Cancer
The prognosis of ovarian cancer is primarily determined by FIGO stage at diagnosis, with 5-year overall survival rates ranging from 70-95% for early-stage disease (Stage I-II) to only 10-40% for advanced-stage disease (Stage III-IV). 1, 2
Key Prognostic Factors
Stage at Diagnosis
Stage is the most powerful predictor of survival in ovarian cancer:
Stage I: Cancer limited to the ovaries
- Stage IA/IB (well-differentiated, non-clear cell): Excellent prognosis with surgery alone
- Stage IC: Requires adjuvant chemotherapy
Stage II: Cancer involving one or both ovaries with pelvic extension
- 5-year survival: 70-80% with optimal treatment
Stage III: Cancer involving ovaries with peritoneal implants outside pelvis and/or positive regional lymph nodes
- 5-year survival: 15-40% depending on residual disease after surgery
Stage IV: Distant metastases beyond peritoneal cavity
- 5-year survival: approximately 10-20%
Histological Type and Grade
Different histological subtypes have varying prognoses:
- High-grade serous carcinoma: Most common (70-80% of advanced cases), aggressive behavior
- Low-grade serous carcinoma: Better prognosis than high-grade, but less responsive to chemotherapy
- Endometrioid carcinoma: Generally favorable prognosis, especially early-stage
- Clear cell carcinoma: Good prognosis in stage I, poor in advanced stages due to chemoresistance
- Mucinous carcinoma: Good prognosis if confined to ovary, poor if advanced
Residual Disease After Surgery
The volume of residual disease after cytoreductive surgery significantly impacts survival:
- No visible residual disease: Best prognosis
- Optimal cytoreduction (<1 cm residual): Intermediate prognosis
- Suboptimal cytoreduction (>1 cm residual): Poor prognosis
Other Prognostic Factors
- Age: Younger patients have better outcomes
- Performance status: Better physical condition correlates with improved survival
- Presence of ascites: Negative prognostic factor
- Dense adhesions: Negative prognostic factor
- BMI: Higher BMI associated with worse survival (RR=1.06 per 5-unit increase) 3
- Smoking: Current smokers have worse outcomes (RR=1.17 compared to never smokers) 3
Survival Statistics
- Overall incidence and mortality: In the European Union, crude incidence is 18/100,000 women/year with mortality of 12/100,000 women/year 1
- Median age at diagnosis: 63 years 1
- Early-stage disease: 5-year survival rates of 70-95% with appropriate treatment 2
- Advanced-stage disease: 5-year survival rates of 10-40% 2
- BRCA-related ovarian cancer: Better response to treatment, particularly with PARP inhibitors (5-year survival approximately 70%) 2
- Recurrence rates: Despite initial remission rates of 80%, approximately 75% of advanced-stage patients relapse within 2 years 2
Special Considerations
Cure Potential
Approximately 20% of women with advanced-stage ovarian cancer survive beyond 12 years after treatment and are effectively cured 4. This percentage could potentially increase to 50% with maximal debulking surgery and intraperitoneal chemotherapy 4.
Histotype Reclassification
Recent studies show that about 23% of ovarian cancers may be misclassified based on morphology alone, with immunohistochemistry helping to refine diagnosis 5. This is particularly important as prognosis varies significantly by histotype.
Recurrence Risk Factors
Key factors influencing recurrence include histological type, FIGO stage, and postoperative chemotherapy cycles 6. Early diagnosis remains crucial for reducing recurrence risk.
Common Pitfalls in Prognostication
- Failure to accurately stage: Proper surgical staging is essential for accurate prognostication
- Histological misclassification: Particularly between high-grade endometrioid and high-grade serous carcinomas
- Overlooking molecular features: BRCA status significantly impacts prognosis and treatment response
- Underestimating the importance of complete cytoreduction: The goal should be no visible residual disease
By understanding these prognostic factors, clinicians can better counsel patients about expected outcomes and guide treatment decisions to optimize survival.