Understanding Chemotherapy and its Side Effects

Dr. Skip Burris from the Sarah Cannon Research Institute discusses chemotherapy and its side effects.

Q: Welcome to Understanding Cancer.  Today we’re talking to Dr. Skip Burris, director of drug development at the Sarah Cannon Research Institute.  Welcome back, Skip.

A: Thanks.

Q: What I want to do today is explore the different types of cancer therapies that patients might be offered.  And I know that when a patient has an initial consultation, they hear a lot about the different treatment options they may have, and it kind of goes in one ear and out the other.  And so the purpose really is that they have a recapping of that discussion that they can visit and to maybe answer some of the questions they might have.  So I think the first thing I want to ask about is chemotherapy in general.  When you’re talking to a new patient, how do you describe to them what chemotherapy is?

A: And chemotherapy is that word that sounds ominous, that sounds scary, and actually I think back to when I was going through my fellowship in the late ‘80s, that some of the chemotherapy meetings were still held in conjunction with the infectious disease meetings, and we were talking about antibiotics and chemotherapy at the same time.  And really, many of the chemotherapy drugs have come out of the same research that brought us antibiotics, that brought us the drugs that kill bacteria and viruses.

So chemotherapy is just simply a medicine that’s going to get inside of a cell and cause it to die.  You know, no different than Penicillin working against the bacteria that invade your lungs or another part of your body, that these chemotherapy drugs, potentially with more side effects, and we need to manage those, and much stronger in terms of their ability to kill cells, but they get inside these cancer cells and interfere with their ability to divide and cause them to die.

Q: Now, while the chemotherapy is attacking the cancer cells, does it also attack the cells, I mean, the body’s normal cells?

A: Well, and that’s the trick to managing the dose and the schedule for the chemotherapy drug.  So the simplest way to think about it is chemotherapy is going to be killing cells that are dividing rapidly, so cancer cells are dividing too fast.  That’s what makes them a cancer cell.  So that’s part of the target for the chemotherapy.

And then you think about the side effects of chemotherapy.  It tends to be those other cells that are still growing and dividing when you’re a fully grown adult.  So that’s why we see some hair loss.  Not with all drugs, and certainly there’s more drugs nowadays that don’t have the hair loss associated, but that’s why you’ll see hair loss.  Your hair’s growing every day, and the chemotherapy drug will get into those hair cells.

That’s why the blood counts will go up and down.  Our bone marrow is our factory that’s making these red cells and white cells and platelets that keep us from bleeding, and the chemotherapy gets into the bone marrow and interferes with the production of those cells, causes those cells to die, so your blood counts will go up and down as well.

And then lastly, the mucosal membrane, so that lining of our mouth all the way down through our gastrointestinal tract.  We’re constantly making a new lining to that organ, turning over those cells, and so that’s why sometimes you’ll see some mouth sores and sometimes you’ll see some of the gastrointestinal toxicity that you see with chemotherapy.

Q: I think of the decade of the sort of late ‘80s, early ‘90s as the decade of supportive care improvements.  So, you know, we developed these new chemotherapy compounds in the ‘70s and ‘80s, and they had all these side effects, and then we spent a decade, in essence, developing ways to reduce the side effects.  And it seems the net effect of that is chemotherapy is really much more tolerable today than it used to be.  I’m curious, what side effects are most treatable or manageable today?

A: So you brought up an interesting point about getting drugs to be able to be tolerable, and nausea was our first big hurdle.  So we had some very good drugs that have come along to help treat nausea, and in fact I joke nowadays that in fact if you’re still having nausea with your chemotherapy, you probably need another doctor or another nurse taking care of you.  You should be able to take care of that side effect.

We have great medicines.  The medicines work a couple different ways.  And actually, some of the medicines that work the best actually tell your brain that you’re not nauseated, and you don’t have that reaction to the chemotherapy.  It’s interesting now, it’s funny, in our clinic one of our battles now is to not have patients eating in the chemotherapy room.  So it used to be nobody wanted to think about food—

Q: [Laughs.]

A: –and now we’ve got to be careful for the smells and the tastes that are showing up there.

Q: Interesting.  What about the effect on the blood cell counts?  Can that be prevented or treated?

A: That can be, and I think we need to be careful and yet aggressive about that.  There’s been news out there [late] about how much we should push the drugs that will help keep our red count up.  So your red blood cells carry oxygen.  That’s when we commonly hear the phrase of somebody being anemic or having low blood.  And really keeping up the red count, keeping up your hemoglobin hematocrit is very, very important.  It helps to make the therapies work better and it’s really probably one of the primary reasons why patients feel fatigue.

I think that that’s an important part of the therapy.  Doctors need to continue monitoring that.  And while any therapy can be overdone, using those drugs that can support the red blood count, the erythropoietin compounds, very, very important to avoid blood transfusions where possible and to keep your energy level up where it can be appropriate.

The other factors that we have now that’s really important is the white cell stimulator.  So these are drugs that in fact cause the white blood count to increase, Filgrastim and Pegfilgrastim, these drugs that will cause the white count to come back to normal more quickly, or actually, in some cases, avoiding from going too low.  The white cells are your important infection fighting mechanism, and anything you can do to keep your body strong, to keep infections away from the side effects of chemotherapy really will be a better outcome for the patient.

Q: Also isn’t the rate of the white blood cell recovery after you give somebody chemotherapy something that’s important to control in terms of the overall management of the patient?

A: It is.  I think that we look at it with using white cell stimulators, using the Filgrastim and Pegfilgrastim compounds, trying to use something like that to avoid infection is one part.  But you hit a key part there, too, where in terms of being able to give your therapy on time.  If your counts are slow to come back and we have to delay your therapy for a week, that’s not good for treating your cancer.  Part of successfully treating cancer is getting that regimen on time and getting rid of those cells as quickly as possible.  So that sort of support so that your blood counts are ready for the next treatment is a key component.

Q: Are there any patient populations that are more likely to have problems with their blood counts than others?

A: So as you age, just quite naturally, your bone marrow as a factory or as a garden that’s making all these white cells and red cells, begins to age, and like any other organ in your body, so your bone marrow is not as cellular, not as active.  So patients, as they get older, need to be carefully considered for use of these agents.  And I certainly think patients over the age of 65, over the age of 70, are very key folks to consider for that.

I also think we need to look at patients that have co-morbid conditions, patients that have diabetes or arthritic problems or other situations where getting too weak, having your blood counts too low, getting a secondary infection, those are important places also to avoid having your counts get too low.

And then lastly, a point we often forget about, is many of our patients are able to continue working through their chemotherapy.  I think continuing to work, in addition to the economic advantages, certainly is good for your state of mind.  I mean, just keep on with your life, keep doing what you’re doing.  So keeping your white blood count up improves the energy level, less susceptible to infection, and often makes you feel like going to work and decreases the risk of being around other people in the work place.

Q: Now, we didn’t mention platelets, which is the third blood element.  I know that a low platelet count, or thrombocytopenia, isn’t a very frequent complication of chemotherapy, but it does occur.  Is there anything that can be done about that?

A: So low platelets, a difficult issue.  As you mentioned, it’s not as common as seeing the red count and the white blood count be lower.  But in fact if the platelet count gets too low, the physician worries about bleeding, and that can be a delay in getting your next treatment.  That’s something you like to avoid.  And doctors don’t like to give platelet transfusions to patients if they can avoid it at all.

There are several research initiatives underway.  There is an approved growth factor that will stimulate your platelets to come back.  There’s been some side effects, some flu-like syndromes with that particular growth factor, so it hasn’t been as popular as we’d like, but it can be used in certain scenarios.  But there’s a whole group of new drugs that are out there now for treating thrombocytopenia, low platelets, in patients that have that as a primary disorder.  And we’re beginning to see research with those drugs after chemotherapy to see if we can keep the platelet counts from going down as well.

Q: These are the drugs that are currently being used to treat what we call chronic ITP?

A: Correct, ITP, idiopathic thrombocytopenia purpura, a condition in and of itself, probably due to your immune system, and your platelet counts drop very low.

Q: Okay.  So it seems over the past several years there’s been significant progress in controlling nausea and vomiting, and managing the blood count side effects.  What about hair loss or effects to the mucosal membranes which you mentioned?

A: So, you know, for patients undergoing fairly intense treatments, there are growth factors out there to ask your doctor about which can help the recovery of the mucosal membrane and slow down some of the effects in that direction.  So we actually do have some supportive care treatments that can help recovery.  For example, those patients that might be getting radiation in addition to their chemotherapy, you know, not having that significant mucositis or mouth sores that might hinder your ability to eat and drink.

Alopecia – the biggest thing that’s happened in that regard is really looking at newer ways of giving drugs or giving the chemotherapy drugs and formulations where they’re less sensitive to the hair.  So we’re a little behind in that.  That’s a, to some patients, a cosmetic issue.  To other patients it can be a little more life altering.  But I think we’re beginning to see more and more effort with the development of chemotherapies, as we understand how they work, to put them in preparations or formulations where maybe we can minimize the effects on the hair.

Q: So nothing’s really been created yet that can prevent hair loss?

A: No, nothing that’s—

Q: No.

A: –nothing that actually will stop that.

Q: Okay.  So one thing I’ve noticed is that when patients are receiving chemotherapy, they’re somewhat reluctant sometimes to mention symptoms they may be having to their doctors.  How important is it for them to really bring to your attention whatever it is they’re experiencing?

A: Very important, and I think you’re right.  Patients are hesitant to have their dose reduced or have their dose delayed.  And, you know, the fact of the matter is everybody handles drugs a little differently.  There’s recommendations, not firm parameters, on the amount of drug that should be given to a patient.  And I think the physicians need to hear from the patients what sort of side effects they’re experiencing.

What’s the appropriate dose for one patient might need to be dropped 20% in another patient, so communicating that, where you want the patient to be as healthy as they can, as strong as they can, and have their energy level up while they go through the therapy.  And sometimes dose reductions and dose adjustments need to be made, and that’s very, very important, and patients shouldn’t be hesitant to administer it.  Doctors aren’t going to withhold care or give an inappropriate dose.  They’re looking to give the right dose and the right schedule to each patient.

Q: And perhaps even more relevant, at some level, is there are things that can help patients through their side effects, but if they don’t bring them to your attention, you really can’t do anything.

A: Exactly.  And what might be a number that makes one patient feel weak or tired might not be so for another patient.  All very, very individualized, and I think that communication is very, very key.  There’s a lot of things out there to help patients with regard to helping support their blood counts, helping control their nausea, helping to stimulate their appetite, and only through communication, only mentioning the symptom enables the doctor or nurse to know to prescribe the medicine.

Q: Well, Skip, thank you for your time today, and we really look forward to having you back.

A: Thank you.

[End of recording.]