Ovarian Cancer Care: An Overview of Today’s Treatment Options

Katherine Banwell:

Now that we’ve covered testing, let’s walk through the available options for treating ovarian cancer and discuss who they might be right for.

Let’s start with surgery.

Dr. Kevin Elias:

So, the ideal surgical candidate is a patient who is otherwise relatively healthy, meaning that we think that they’ll be able to recover from surgery, typically within a few weeks of therapy, because we usually want to begin chemotherapy within a month of surgery. It should be possible to remove all sites of disease at the time of the surgery. Now, ovarian cancer, because it can involve other structures in the abdominal cavity, other than just the ovaries and the adjacent gynecologic structures, that could include surgery on the intestines, on the spleen, on the liver, in order to remove all sites of disease.

So, it’s important in choosing the correct surgeon, having a surgeon or surgical team that is comfortable with performing that type of radical surgery. So, those would be the ideal surgical candidates, patients who have disease that’s amenable to removal upfront, and the patient has to be in good functional state that it makes sense for them to pursue a potentially radical surgical option.

Katherine Banwell:

Next might be chemotherapy for some people?

Dr. Kevin Elias:

So, most patients with ovarian cancer will be getting chemotherapy, whether that’s an initial several cycles of chemotherapy to shrink the disease to make the surgery possible, or if they had a primary surgery, chemotherapy afterwards to minimize the risk of recurrence. Chemotherapy for ovarian cancer is primarily intravenous chemotherapy. We talk about medications that are going to be given usually once every three or four weeks, depending on the regimen, and the backbone of chemotherapy for ovarian cancer is what we call platinum-based chemotherapy.

So, that means medications like carboplatin (Paraplatin) and cisplatin (Platinol) that just are platinum, like the metal-based medications, since those are really the most effective medications for treating ovarian cancer. Now, we couple it with other medicines, most commonly things like paclitaxel (Taxol), sometimes medications like doxorubicin. But platinum is really the basis for upfront ovarian cancer therapy.

Katherine Banwell:

You mentioned earlier targeted therapies. Could you go over what they are and what would be appropriate for ovarian cancer patients?

Dr. Kevin Elias:

So, targeted therapies refer to tumor therapies that specifically focus on unique genetic aspects of that tumor. So, that can be an alteration in the DNA of the tumor, it could also be a protein that’s expressed uniquely by the tumor cells. The most common one that we use currently are what are known as the PARP inhibitors. These are oral medications. They’re pills that are taken either once or twice a day after completion of chemotherapy. It’s what we call maintenance therapy.

So, the primary treatment with the surgery and chemotherapy is over, and now the patient will go on a medication they will take every day by mouth in order to minimize the chances of cancer recurrence. So, PARP inhibitors are one type of targeted therapy. The other type of targeted therapy, which is becoming increasingly common, are what are known as antibody drug conjugates. Now, these are intravenous therapies that combine a very small dose of medication with an antibody, just like the antibodies our bodies make against viruses and bacteria.

These are antibodies that have been engineered to target a protein on cancer cells. The most commonly used one right now is what’s known as the folate receptor. So, folate receptor alpha tends to be expressed more in cancer cells than in normal cells. And so, by linking a small dose of chemotherapy to an antibody against that receptor, we can target the chemotherapy specifically to the cancer cells.

Currently, those medications are used primarily for women who have already received chemotherapy, usually as a second or a third line option. However, there are clinical trials going on right now, including one which we’ve just opened at the Cleveland Clinic, where we’re using these medications now in the first line setting as an alternative to traditional chemotherapies because we think that they may be equally effective and potentially much less toxic than traditional types of chemotherapy.

Katherine Banwell:

Oh, that’s great news. What about newer targeted therapy combinations? What’s available?

Dr. Kevin Elias:

So, we are looking at other antibody drug conjugates, particularly for women who don’t express folate receptor. So, there are other protein receptors that we can develop similar type drugs for. And so, there are several of those that are in late-stage clinical trials at the moment. There’s also targeted therapy, which is using immunotherapy. So, there are ways that we can stimulate the immune system to respond to cancer cells.

In general, immunotherapy for ovarian cancer has not been quite as promising as it has been for other types of solid tumors. But that does seem to be changing. There are new immunotherapy medications, that when directed potentially in combination with targeted therapy, might produce meaningful responses. But that’s an area of active research.

Katherine Banwell:

And there’s something called intraperitoneal therapy? Am I pronouncing that correctly?

Dr. Kevin Elias:

Yes, exactly. So, there are two different contexts in which we use intraperitoneal chemotherapy. One is for patients who have had primary surgery.

So, those patients in whom the disease was felt to be amenable to complete removal at the initial surgery. There’s a very narrow group of patients. So, it has to be patients who had at least stage III disease, so disease which is involving not just the pelvic structures, but also the abdominal structures, but in whom we were able to completely remove all visible disease at the time of initial surgery. In those patients, we will sometimes leave a catheter in the abdominal cavity.

So, it’s a small, essentially IV tubing that will actually sit underneath the skin and sit next to the pelvic area. And when the patients come in for their subsequent chemotherapy, we will give part of the chemotherapy intravenously and part of the chemotherapy directly into the abdomen, essentially soaking the cancer cells directly in chemo. It is a more intensive type of chemotherapy because it does involve multiple treatments during each cycle, and it’s a much higher dose of chemo.

So, we’re really looking for patients who are typically on the younger side and generally with very, very good performance status to be considered for that type of therapy. But it is something, again, that patients should ask about if they’re a candidate for, if they’re being evaluated for primary chemotherapy and surgery. The other option as far as intraperitoneal chemotherapy would be the HIPEC I was talking about before. The heated chemotherapy is given intraperitoneally, so directly into the belly, and it’s circulated around through a special pump device during the surgery itself.

And that’s about a 90-minute treatment that’s done while the patient’s under anesthesia. So, those are the two most common types of intraperitoneal therapy. There are some other ones which are still in the investigational setting. Therapies, again, some of which we have in clinical trial, which might also be administered intraperitoneally, the idea being the shorter the distance between the delivery of the drug and the tumor itself, the higher concentration of medication we can deliver to the cancer cells.