Ovarian Cancer
A highly deadly cancer of the female reproductive glands, usually diagnosed late because its early symptoms are vague like bloating and pelvic pain.
Emergency Management: Malignant bowel obstruction requiring nasogastric tube decompression, high-dose steroids, or palliative diversion surgery. Ovarian torsion presents as acute, severe pelvic pain.
Ovarian cancer encompasses a group of malignancies arising from the ovaries, fallopian tubes, or primary peritoneum. The most common and lethal subtype is High-Grade Serous Carcinoma (HGSC), an epithelial tumor that often originates in the distal fallopian tube.
Detailed Overview
Ovarian cancer is the leading cause of death from gynecologic malignancies. It is dubbed the 'silent killer' because it remains asymptomatic in early stages; over 70% of patients are diagnosed at an advanced stage (III or IV) when the cancer has spread throughout the peritoneal cavity. While the disease is highly responsive to platinum-based chemotherapy initially, recurrence and chemoresistance are common. Germline and somatic BRCA1/2 mutations play a major role in its pathogenesis and open avenues for targeted therapy with PARP inhibitors.
Epidemiology & Demographics
Causes over 13,000 deaths annually in the US. Median age at diagnosis is 63 years. Lifetime risk is about 1.3% for the general female population, but increases dramatically (up to 40-60%) in women with BRCA mutations.
Etiological Mechanism
The exact etiology is debated, but the 'incessant ovulation' hypothesis suggests that repeated trauma and repair of the ovarian epithelium during ovulation predisposes to malignant transformation. More recently, overwhelming evidence shows that High-Grade Serous Carcinoma originates from Serous Tubal Intraepithelial Carcinoma (STIC) lesions in the fimbriae of the fallopian tubes.
Primary Causes
Germline mutations (BRCA1, BRCA2, Lynch Syndrome)
Incessant ovulation (nulliparity, early menarche, late menopause)
In High-Grade Serous Carcinoma, p53 mutations occur early in the fallopian tube epithelium (forming a p53 signature). This progresses to STIC, which eventually exfoliates malignant cells. These cells implant onto the ovary and the peritoneum. The cancer spreads primarily via transcoelomic dissemination (shedding into the peritoneal cavity) following the normal flow of peritoneal fluid, leading to diffuse carcinomatosis, omental caking, and malignant ascites. Implantation on the diaphragm blocks lymphatic drainage, exacerbating ascites.
Diagnostic Criteria & Guidelines
Diagnosis and staging are surgical. Preoperatively, suspicious ultrasound findings (solid components, thick septations, ascites) combined with elevated CA-125 suggest the diagnosis. Definitive diagnosis requires surgical pathology from tumor resection or biopsy.
Primary debulking surgery (Cytoreductive Surgery) to achieve R0 (no macroscopic residual disease), involving total abdominal hysterectomy, bilateral salpingo-oophorectomy (TAH-BSO), omentectomy, and tumor resection. This is followed by 6 cycles of Platinum-based chemotherapy: IV Paclitaxel (175 mg/m²) and Carboplatin (AUC 5-6) every 3 weeks. If the tumor is deemed unresectable initially, Neoadjuvant Chemotherapy (NACT) is given for 3 cycles, followed by interval debulking surgery.
Second-Line & Adjunctive Therapy
Maintenance Therapy: For patients with BRCA mutations or HRD-positive tumors who respond to platinum chemotherapy, PARP inhibitors (e.g., Olaparib 300 mg PO BID or Niraparib) are used to significantly prolong progression-free survival. Bevacizumab (anti-VEGF) is also used for maintenance in advanced stages.
Surgical & Procedural Management
Aggressive cytoreductive surgery. The survival of the patient is directly correlated with the volume of residual disease left behind. Bowel resections and splenectomy may be necessary to remove all visible tumor.
Patient Counseling & Advice
Inform the patient that while ovarian cancer responds very well to initial chemotherapy, the risk of recurrence is high (over 70% for advanced disease). Discuss the importance of genetic testing not only for their own targeted therapy (PARP inhibitors) but to alert family members who might need prophylactic surgery.
Follow-Up & Monitoring Schedule
History, physical exam, and CA-125 levels every 3 months for 2 years, then every 6 months for 3 years. CT scans are performed if there is clinical suspicion of recurrence or rising CA-125.
Preventive Strategies
For high-risk BRCA mutation carriers, risk-reducing salpingo-oophorectomy (RRSO) between ages 35-40 (after childbearing) reduces risk by 80-90%. Oral Contraceptive Pills (OCPs) for >5 years reduce risk by 50% in the general population.
5-year survival for Stage I is >90%. For Stage III/IV, 5-year survival drops to 30-40%. Despite high initial response rates to chemotherapy, most advanced cases recur and eventually become platinum-resistant.