Understanding platinum-sensitive vs. platinum-resistant disease
- About 80 percent of ovarian cancer patients will go into remission after their initial treatment.
- Unfortunately, a majority of women may experience a cancer recurrence.
- Women with cancer that responds to chemotherapy for more than six months are considered platinum-sensitive.
- Platinum-sensitive patients may see more benefit from treatment with PARP inhibitor.
There are treatment options for women after the first standard treatments for ovarian cancer.
Many patients with ovarian cancer will respond to initial treatment with chemotherapy in that actually puts their disease into remission. Indeed about 80 percent of women will go into remission following chemotherapy and surgery. Unfortunately, many will experience a recurrence.
“We divide those patients into what we call platinum-sensitive and platinum-refractory disease,” says Dr. Jeanne Schilder, division director of gynecologic oncology at Indiana University Medical Center.
Women whose cancer responds to their chemotherapy for more than six months are considered platinum sensitive, and they have an excellent chance of responding to some other type of chemotherapy after their cancer recurs. Women with platinum refractory (or platinum resistant) disease, meaning their cancer comes back within 6 months after treatment, are a challenge. We have many clinical trials trying to identify how to manage that difficult situation, and I would suggest that any patient with recurrent disease in the platinum refractory setting should be looking for a clinical trial that they might be eligible for and that they would want to participate in.
Clinical trials are research studies that compare the most effective known treatment for a specific type or stage of cancer with a new approach. This can be a new drug, or combination of drugs or a different way of using established therapies. Many of the treatments that doctors use today were discovered, tested, and first made available to patients in clinical trials.
Dr. Schilder says anybody with any type of cancer should consider a clinical trial even at the time of their initial diagnosis.
Using a PARP Inhibitor
Research has shown that patients who respond to platinum based chemotherapy in the upfront setting may benefit from maintenance treatment with a PARP inhibitor or the drug bevacizumab. PARP inhibitors help keep cancer cells from repairing their damaged DNA, making them more likely to die. They’re an oral medication you can take at home, so you don’t have to go to an infusion center or schedule visits with your physician to receive them.
While initially, women with a BRCA-1 or BRCA-2 genetic mutation had been shown to respond especially well to PARP inhibitors after recurrence, and then in what’s called maintenance therapy, newer research has shown that women with the BRCA gene mutation (and indeed almost all women), can consider using PARP inhibitors throughout their treatment.
Newly-Diagnosed Epithelial Ovarian Cancer
The PARP inhibitor Zejula (niraparib) has been approved by the FDA for all women with newly-diagnosed ovarian cancer irrespective of whether the tumor is HRD. The drug is used after successful treatment with a platinum-based chemotherapy, the mainstay chemotherapy for ovarian cancer.
The PARP inhibitor Lynparza (olaparib) is approved for women newly diagnosed with ovarian cancer and with a germline or somatic mutation in BRCA1/2.
Lynparza is also approved in combination with Avastin (bevacizumab) for women with HRD. Avastin is a blood vessel growth inhibitor, which works by starving the tumor of vital nutrients needed to grow.
Using PARPs To Treat Recurrence
Unfortunately, too often, ovarian cancer comes back.
For women with ovarian cancer who have had a recurrence and responded to platinum-based chemotherapy, Lynparza, Zejula and another PARP inhibitor called Rubraca (rucaparib) are FDA approved for use as a maintenance therapy, regardless of whether a woman has a BRCA mutation or HRD.
For some women who have had prior chemotherapy treatments, Rubraca, Zejula or Lynparza may also be options. These uses are based on factors such as number of prior therapies and BRCA mutation or HRD.
The different PARP inhibitors do have some varying side effects, which oncologists need to evaluate carefully.
However Dr. Amanika Kumar of The Mayo Clinic who spoke to SurvivorNet, cautioned that women still need to speak with their doctor to evaluate the benefit of taking a PARP inhibitor to extend life, because there are very real side effects due to the toxicity of the drug. “Patients with HRD (homologous recombination deficiency) have a far better response than those without and those with BRCA mutations even more so. It is on us as clinicians to help patients understand the risks and benefits of treatment. Patients that have no mutation or HRD may choose not to go on maintenance (in fact I recommend they don’t) because there is real toxicity to these meds.”
The new understanding evolving around the use of PARP inhibition is a major reason why genetic testing is so important, and recommended to patients when they’re first diagnosed.
Learn more about SurvivorNet's rigorous medical review process.
Understanding platinum-sensitive vs. platinum-resistant disease
- About 80 percent of ovarian cancer patients will go into remission after their initial treatment.
- Unfortunately, a majority of women may experience a cancer recurrence.
- Women with cancer that responds to chemotherapy for more than six months are considered platinum-sensitive.
- Platinum-sensitive patients may see more benefit from treatment with PARP inhibitor.
There are treatment options for women after the first standard treatments for ovarian cancer.
Many patients with ovarian cancer will respond to initial treatment with chemotherapy in that actually puts their disease into remission. Indeed about 80 percent of women will go into remission following chemotherapy and surgery. Unfortunately, many will experience a recurrence.
Read More “We divide those patients into what we call platinum-sensitive and platinum-refractory disease,” says
Dr. Jeanne Schilder, division director of gynecologic oncology at Indiana University Medical Center.
Women whose cancer responds to their chemotherapy for more than six months are considered platinum sensitive, and they have an excellent chance of responding to some other type of chemotherapy after their cancer recurs. Women with platinum refractory (or platinum resistant) disease, meaning their cancer comes back within 6 months after treatment, are a challenge. We have many clinical trials trying to identify how to manage that difficult situation, and I would suggest that any patient with recurrent disease in the platinum refractory setting should be looking for a clinical trial that they might be eligible for and that they would want to participate in.
Clinical trials are research studies that compare the most effective known treatment for a specific type or stage of cancer with a new approach. This can be a new drug, or combination of drugs or a different way of using established therapies. Many of the treatments that doctors use today were discovered, tested, and first made available to patients in clinical trials.
Dr. Schilder says anybody with any type of cancer should consider a clinical trial even at the time of their initial diagnosis.
Using a PARP Inhibitor
Research has shown that patients who respond to platinum based chemotherapy in the upfront setting may benefit from maintenance treatment with a PARP inhibitor or the drug bevacizumab. PARP inhibitors help keep cancer cells from repairing their damaged DNA, making them more likely to die. They’re an oral medication you can take at home, so you don’t have to go to an infusion center or schedule visits with your physician to receive them.
While initially, women with a BRCA-1 or BRCA-2 genetic mutation had been shown to respond especially well to PARP inhibitors after recurrence, and then in what’s called maintenance therapy, newer research has shown that women with the BRCA gene mutation (and indeed almost all women), can consider using PARP inhibitors throughout their treatment.
Newly-Diagnosed Epithelial Ovarian Cancer
The PARP inhibitor Zejula (niraparib) has been approved by the FDA for all women with newly-diagnosed ovarian cancer irrespective of whether the tumor is HRD. The drug is used after successful treatment with a platinum-based chemotherapy, the mainstay chemotherapy for ovarian cancer.
The PARP inhibitor Lynparza (olaparib) is approved for women newly diagnosed with ovarian cancer and with a germline or somatic mutation in BRCA1/2.
Lynparza is also approved in combination with Avastin (bevacizumab) for women with HRD. Avastin is a blood vessel growth inhibitor, which works by starving the tumor of vital nutrients needed to grow.
Using PARPs To Treat Recurrence
Unfortunately, too often, ovarian cancer comes back.
For women with ovarian cancer who have had a recurrence and responded to platinum-based chemotherapy, Lynparza, Zejula and another PARP inhibitor called Rubraca (rucaparib) are FDA approved for use as a maintenance therapy, regardless of whether a woman has a BRCA mutation or HRD.
For some women who have had prior chemotherapy treatments, Rubraca, Zejula or Lynparza may also be options. These uses are based on factors such as number of prior therapies and BRCA mutation or HRD.
The different PARP inhibitors do have some varying side effects, which oncologists need to evaluate carefully.
However Dr. Amanika Kumar of The Mayo Clinic who spoke to SurvivorNet, cautioned that women still need to speak with their doctor to evaluate the benefit of taking a PARP inhibitor to extend life, because there are very real side effects due to the toxicity of the drug. “Patients with HRD (homologous recombination deficiency) have a far better response than those without and those with BRCA mutations even more so. It is on us as clinicians to help patients understand the risks and benefits of treatment. Patients that have no mutation or HRD may choose not to go on maintenance (in fact I recommend they don’t) because there is real toxicity to these meds.”
The new understanding evolving around the use of PARP inhibition is a major reason why genetic testing is so important, and recommended to patients when they’re first diagnosed.
Learn more about SurvivorNet's rigorous medical review process.
