Ovarian cancer is the fifth most common cause of cancer deaths in women and the leading cause of death among cancers of the female reproductive system in the United States. More than 21,400 women in the United States are expected to be diagnosed with the disease in 2021, and 13,770 will die from it. (1) Up to 90% of ovarian cancer cases are epithelial in origin, and 7 of every 10 epithelial ovarian cancers are high-grade serous tumors. (2)
First-line treatment for ovarian cancer typically involves surgical staging, followed by debulking surgery and, in most patients, platinum- and taxane-based chemotherapy with or without bevacizumab, a monoclonal antibody. (3) Some patients require neoadjuvant chemotherapy to shrink the tumor before surgery. Usually, 3 cycles of chemotherapy are given before surgery, with at least 3 cycles after surgery. (4) Adjuvant therapy with hormonal agents may also be an option for patients with tumors of specific histologic subtypes. (3) Despite these treatments, 85% of patients with advanced ovarian cancer will experience recurrence at some point after chemotherapy. (5)
First-line therapy is often followed by maintenance therapy. According to Rebecca Previs, MD, a gynecologic oncologist at Duke Cancer Center in Durham, North Carolina, all patients should be offered first-line maintenance therapy. "The concept of maintenance," Previs explains, "is to enable patients to have a higher rate of cure and to prevent the cancer from coming back, because we know once a cancer comes back, it's even more difficult to treat."
Whether or not a patient elects to start maintenance therapy depends on her preferences, her goals of care, and her understanding of the data. Previs counsels patients about Food and Drug Administration (FDA) approvals of all frontline maintenance options, including potential adverse effects (AEs). "Those patients who require multiple blood transfusions and multiple dose reductions are the patients who may opt not to continue maintenance therapy. It is a very personal [choice in] each patient's cancer journey," she said.
Choosing a Maintenance Therapy
A number of options are available for patients who elect to undergo maintenance therapy. The choice of maintenance therapy must be individualized based on the patient's clinical features and preferences, with consideration of the National Comprehensive Cancer Network (NCCN) guideline recommendations and FDA-approved indications. For patients with stage IV disease or recurrent ascites, Previs typically recommends bevacizumab as maintenance therapy. "I have a very honest conversation with patients at the time of diagnosis and treatment to really discuss that the addition of bevacizumab, while it has shown an improvement in progression-free survival, [it has not] translated in follow-up with overall survival," she explained. "It's really important to break these clinical trials down to a patient level and explain, 'What does progression-free survival mean?' 'How does this translate into overall survival?' 'What are the costs associated with additional maintenance therapy?' By cost, I mean financial as well as the time burden to patients."
For patients with advanced ovarian cancer, emerging evidence shows that PARP inhibitors are effective for first-line maintenance after chemotherapy. (3)...