What is the optimal adjuvant therapy after ovarian surgery for cancer?

From the Guidelines

The optimal adjuvant therapy after ovarian cancer surgery typically consists of platinum-based combination chemotherapy, most commonly carboplatin (AUC 5-6) plus paclitaxel (175 mg/m² over 3 hours) administered every 3 weeks for 6 cycles, as recommended by the most recent guidelines 1. This regimen should begin within 6 weeks of surgery for best outcomes. For patients with advanced disease (stage III-IV) who had optimal cytoreduction, adding bevacizumab (15 mg/kg every 3 weeks) during chemotherapy and continuing as maintenance for up to 15 months may improve progression-free survival. For patients with BRCA mutations or homologous recombination deficiency, PARP inhibitor maintenance therapy (such as olaparib 300 mg twice daily, niraparib 200-300 mg daily, or rucaparib 600 mg twice daily) following completion of platinum-based chemotherapy significantly extends progression-free survival. Treatment selection should be individualized based on disease stage, surgical outcome (optimal vs. suboptimal debulking), histologic subtype, molecular profile, and patient performance status. Some key points to consider include:

• The choice of chemotherapy regimen may depend on the patient's overall health and ability to tolerate treatment 1.
• The optimal duration of treatment remains controversial, but most guidelines recommend 6 cycles of chemotherapy 1.
• The addition of bevacizumab to chemotherapy may improve progression-free survival in patients with advanced disease 1.
• PARP inhibitors may be effective in patients with BRCA mutations or homologous recombination deficiency 1. These regimens are effective because platinum agents create DNA crosslinks while taxanes stabilize microtubules, preventing cancer cell division. PARP inhibitors exploit DNA repair deficiencies in susceptible tumors, while bevacizumab inhibits tumor angiogenesis. Potential toxicities requiring monitoring include myelosuppression, neuropathy, and hypersensitivity reactions. It's worth noting that the evidence for adjuvant therapy in ovarian cancer is constantly evolving, and treatment decisions should be made on a case-by-case basis, taking into account the latest research and guidelines 1.

From the FDA Drug Label

For patients with carcinoma of the ovary the following regimen is recommended:

1. For previously untreated patients with carcinoma of the ovary, one of the following recommended regimens may be given every 3 weeks a. Paclitaxel administered intravenously over 3 hours at a dose of 175 mg/m2 followed by cisplatin at a dose of 75 mg/m2; or b Paclitaxel administered intravenously over 24 hours at a dose of 135 mg/m2 followed by cisplatin at a dose of 75 mg/m2.

The optimal adjuvant therapy after ovarian surgery for cancer is paclitaxel in combination with cisplatin. The recommended regimen is:

• Paclitaxel 175 mg/m2 IV over 3 hours followed by cisplatin 75 mg/m2 every 3 weeks, or
• Paclitaxel 135 mg/m2 IV over 24 hours followed by cisplatin 75 mg/m2 every 3 weeks 2. Carboplatin can also be used as an alternative, with a recommended dose of 300 mg/m2 IV on day 1 every 4 weeks for 6 cycles, in combination with cyclophosphamide 600 mg/m2 IV on day 1 every 4 weeks for 6 cycles 3.

From the Research

Optimal Adjuvant Therapy

The optimal adjuvant therapy after ovarian surgery for cancer is a topic of ongoing research and debate. Several studies have investigated the efficacy of different chemotherapy regimens in this setting.

• The 3-weekly regimen of carboplatin and paclitaxel is considered the backbone of first-line adjuvant chemotherapy for advanced ovarian cancer 4.
• Dose-dense weekly administration of paclitaxel in combination with 3-weekly carboplatin has been shown to have enhanced antitumor activity and improved tolerance 4.
• The addition of bevacizumab to carboplatin and paclitaxel has been investigated in several studies, with mixed results. One study found that the combination of bevacizumab, carboplatin, and paclitaxel improved progression-free survival and overall survival in patients with platinum-sensitive recurrent ovarian cancer 5, 6.
• Other studies have compared the efficacy of different chemotherapy regimens, such as pegylated liposomal doxorubicin and carboplatin versus paclitaxel and carboplatin, in patients with platinum-sensitive ovarian cancer 7.

Chemotherapy Regimens

The choice of chemotherapy regimen depends on various factors, including the stage and histology of the disease, as well as the patient's performance status and prior treatment history. Some common chemotherapy regimens used in the adjuvant setting for ovarian cancer include:

• Carboplatin and paclitaxel 4, 5, 6
• Pegylated liposomal doxorubicin and carboplatin 7
• Bevacizumab, carboplatin, and paclitaxel 5, 6

Safety and Efficacy

The safety and efficacy of these chemotherapy regimens have been evaluated in several studies. Common adverse events associated with these regimens include hematologic toxicity, nausea, and fatigue 5, 7, 6. However, the addition of bevacizumab to chemotherapy has been shown to improve overall survival in patients with platinum-sensitive recurrent ovarian cancer 6.