CyberKnife: Leading-Edge Treatment for Prostate Cancer Patients

This is Weekly Dose of Wellness, brought to you by MemorialCare Health System. Here's Deborah Howell.

Deborah Howell (Host): And welcome to the show. I am Deborah Howell, and our guest today is Dr. Asif Harsolia, board-certified radiation oncology specialist at MemorialCare Orange Coast Medical Center, and we’ll be discussing the benefits of CyberKnife radiosurgery for the treatment of prostate cancer today. Welcome, Dr. Harsolia.

Asif Harsolia, MD: Thank you for having me.

Deborah Howell (Host): Our pleasure. So, according to the American Cancer Society, prostate cancer is the second leading cause of cancer death in American men. 65% of all prostate cancers are found in men ages 65 through 69. So, Dr. Harsolia, what is CyberKnife radiosurgery, and how long has this method of radiation therapy been in use?

Asif Harsolia, MD: Well, CyberKnife is an advanced form of robotic radiation therapy. It was initially developed at Stanford almost 20 years ago, initially to treat tumors in the brain by a neurosurgeon by the name of Dr. John Adler. And due to its ability to deliver very high doses of radiation with submillimeter precision, it was found to be particularly effective in treating tumors in areas that normally would be very challenging for a surgeon to reach, such as around the sensitive nerves of the eye. So with the success of treating these tumors in critical areas of the brain, people began looking at treating other sites in the body, and they started off looking at spine and lung and liver, and then eventually the prostate itself.

Deborah Howell (Host): Interesting. Now, while CyberKnife is used to treat various types of cancer, why is it considered to be one of the most effective treatment options, particularly for prostate cancer?

Asif Harsolia, MD: I think a few of the things make the CyberKnife particularly well-suited for the treatment of prostate cancer. First, CyberKnife has the unique ability to very accurately track the movement of tumors and the motion of organs, such as the prostate, in real time. So this essentially allows us to deliver more precise doses of radiation to the target itself, with less doses to the surrounding organs, such as the bladder and the rectum, which are adjacent to the prostate. The second thing that makes CyberKnife particularly well suited to the treatment of prostate cancer is that the beams are able to come into the body from hundreds of different angles. So, for example, we're able to use, you know, let's say 200 beams to treat the prostate. And each individual beam is essentially 1/200th of the dose. So where they intersect on the prostate, you have a dose that's 200 times greater. So essentially, a few millimeters away from the prostate, you can have a miniscule dose. And then in your target itself, you can have very high doses that are very effective in destroying cancer. So, this is particularly useful in sparing, for example, the urethra, which is a tube that we urinate out of that runs right through the center of the prostate gland. We can essentially deliver dose to the prostate all around the urethra while creating a nice little donut hole around the urethra, giving less dose to this important structure.

Deborah Howell (Host): That is fabulous. Now, is CyberKnife often used in conjunction with other cancer treatments like surgery or chemotherapy?

Asif Harsolia, MD: You know, depending on the area of the body that we're treating, CyberKnife, yes, can be used in conjunction with surgery and chemotherapy. You know, for example, in brain, we'll remove the tumor and then sometimes treat afterwards. But for prostate cancer in particular, we sometimes use CyberKnife in more advanced cases in conjunction with hormonal therapy like Lupron, which is designed to sort of suppress the male testosterone. At Orange Coast Memorial, we're actually very fortunate to have a clinical trial open that's looking at the use of CyberKnife for the treatment of more aggressive forms of prostate cancer in addition to treating our low-risk patients.

Deborah Howell (Host): Well, best of luck with that. Now, is CyberKnife radiation therapy usually the first course of treatment for prostate cancer? And also, how do you determine if a patient is best suited for this treatment option?

Asif Harsolia, MD: So that's a great question. So usually what we do is we meet with the patient in person for a consultation. And usually we go in detail into their history, their physical exam findings, what their urinary and rectal function is like, pathology, blood work. We use all these different factors to kind of determine the optimal treatment option for our patient. Additionally, we try to work very closely with the patient's urologist and their other physicians in trying to determine the best course of care for each individual patient. If a patient is found to be a good candidate for the procedure, then yes, CyberKnife can often be used as their first line of treatment. And for most patients, it's usually the only course of therapy that they'll need.

Deborah Howell (Host): And what can a patient expect during CyberKnife therapy, Doctor?

Asif Harsolia, MD: So to have a successful procedure, first you sort of have to have some advanced preparation. Usually, we will work closely with the patient's urologist to coordinate the placement of these special gold seed markers which go into the gland to track the motion so the CyberKnife can actually track the motion accurately. And then at the same time, sometimes we'll place a special gel called space OAR to separate the rectum away from the prostate to allow for even less side effects. And then after that, there's usually a simulation that's done to kind of plan and map out the treatment. And we use advanced imaging techniques like an MRI and a CAT scan to essentially create a three-dimensional reconstruction of all the patient's internal anatomy. And so what happens is that we work very closely with a highly trained team of physicists and dosimetrists to come up with a plan that's specific to each patient's situation and anatomy. So the patients usually end up receiving five treatments as an outpatient and even though the name says CyberKnife, there's actually no pain or cutting or anesthesia. It's very similar to just getting an x-ray. You lay on the table and you don't feel anything. And the procedure is usually over within a few hours. Most patients can just drive themselves home even the same day, so there's no admission or anything like that.

Deborah Howell (Host): Well, that is certainly one of the advantages of CyberKnife for the treatment of prostate cancer. Are there others compared to other radiation modalities?

Asif Harsolia, MD: Yeah, I think, you know, compared to other radiation modalities, you know, initially, you know, for decades, we've used a radiation technique called brachytherapy. You know, before the technology became so advanced, brachytherapy had some significant advantages in that it allowed us to implant radiation directly, you know, surgically directly into the prostate gland itself, but it was an invasive procedure. And one of the nice things about the CyberKnife is it's able to deliver doses that are very similar to those doses with brachytherapy, but it's able to do this using external beam technology. So, in a way, it's sort of the best of both worlds in regards to internal and external methods of delivering radiation that we've used in the past. You get the benefits of having the high doses that we deliver with internal radiation, but you don't have any of the invasiveness. You get some of the advantages of the external beam.

Deborah Howell (Host): And now something that every man going through this, of course, is wondering about, what are some of the potential side effects associated with CyberKnife therapy? And what's the typical recovery time after treatment has concluded?

Asif Harsolia, MD: Yeah, so the side effects are usually localized to the area that we're treating. So, most of the side effects are related to organs in close proximity to the treatment, like the bladder and the rectum. So, for example, one of the most common side effects we see with CyberKnife treatment is that there can be swelling of the gland temporarily after the procedure that can result in increased urinary frequency, like having to go to the bathroom more often, or urgency, like when you got to go, you really got to go, that type of thing. And that usually happens two to three weeks after the procedure. Some patients may have some fatigue, but most of these side effects usually resolve four to six weeks after the procedure, and most patients recover pretty well after that. There's also the potential for long-term side effects and the potential impact on sexual function with any type of treatment for prostate cancer. And usually what we'll do is we'll sit down with the patient during the consult and go over these types of side effects and other side effects during the consultation. For most patients, the procedure tends to be fairly well tolerated and more serious side effects are fortunately not very common.

Deborah Howell (Host): That's awesome. What are some of the common signs and symptoms of prostate cancer and when really should men begin routine screenings with their primary care physician?

Asif Harsolia, MD: Most patients usually don't have symptoms until they develop more advanced disease. And so if prostate cancer grows unchecked, people may get things such as blood in the urine or pain with urination or rectal pain, or in really advanced cases, if it's spread to the bone, they can get pain in the bone. And that's one of the reasons why it's so important for patients to have a discussion with their physician as to when to begin screening. Because most early forms of prostate cancer don't have any signs or symptoms at all. It's usually very silent in the beginning. And so a lot of patients consider testing at age 50 or if they have a family history, sometimes even earlier, with a blood test called a PSA. And, you know, even though national organizations differ in their recommendations of when the ideal age is to start, it's an important thing for the patient to have an individual discussion with their physician. In general, prostate cancer tends to increase with age. So that's one of the things to sort of factor in.

Deborah Howell (Host): Yeah. As with everything.

Asif Harsolia, MD: Right, exactly.

Deborah Howell (Host): I have one final question for you, doctor. What are some of the steps someone should take if they've been diagnosed with prostate cancer and are interested in CyberKnife radiation therapy?

Asif Harsolia, MD: Yeah, I think ideally they need to make a consultation with their physician to discuss whether they're a good candidate. And so they should try to find a CyberKnife Center in their area that has expertise and experience in treating prostate cancer. Here at Orange Coast Memorial, we're very fortunate to have a very robust prostate program with one of the teams that has amongst the longest experience in the state in treating patients with the CyberKnife system. Additionally, one of the other nice features, or I guess one of the nice options that are available for patients here is that we do have enrollment in that institutional clinical trial, which might be of particular interest to patients who have more aggressive disease as long as the cancer has not yet spread to other areas of their body.

Deborah Howell (Host): Well, we'll certainly be crossing our fingers for that clinical trial and for some great results for your patients.

Asif Harsolia, MD: Thank you very much.

Deborah Howell (Host): And thank you so much for your time today, Dr. Harsolia. It's been a pleasure to have you on the show for sure.

Asif Harsolia, MD: Thank you. Appreciate being here.

Deborah Howell (Host): For more info or to hear a podcast of this show, go to MemorialCare.org. That's MemorialCare.org. And that's all for this time. Thanks for listening and have yourself a terrific day.