April 23, 2014 | In an interview with Medical Solutions, Jelle Barentsz, Director of the Prostate MR-Reference Center in Nijmegen, Netherlands, describes the advantages of magnetic resonance imaging in diagnosing and treating prostate cancer. Men all around the world are to benefit from the new technology through a global network of specialized “centers of excellence.”
Text: Kerstin Schweighöfer
Photos: Walther Appelt
- Prostate cancer diagnosis still lacks accuracy
- The PSA test and digital rectal examination do not deliver reliable data
- As a result, patients often have to live for years with the potential threat of cancer
- MRI technology provides sharp images of a variety of tissue properties helping to identify tumors
- Moreover, it becomes possible to localize particularly aggressive parts of a prostate tumor
- The method is noninvasive
- A negative multiparametric MRI exam can exclude life-threatening prostate tumors with 97 percent certainty
- Besides more accurate diagnosis, MRI also enables minimally invasive, targeted treatment of prostate cancer
- A global network of “centers of excellence” would make prostate MRI available worldwide
Professor Barentsz, in your clinic’s reception area there are brochures in all languages, even Russian. Where are your patients from?
Barentsz: Many of the roughly 3,000 prostate patients we treat every year in Nijmegen come from abroad, including oil sheikhs, high-level industrial managers, and politicians.
Why is it that these people spare no trouble or expense for the long trip?
Barentsz: Because, thanks to the latest MRI technology, in just over an hour, we can clarify for them whether they have simply an enlarged or chronically inflamed prostate, or a serious case of prostate cancer that can kill them if it is not optimally treated.
Until now, a diagnosis of prostate cancer was deemed to be highly questionable. Patients often face years of uncertainty. Why is that?
Barentsz: Normally the distress begins as soon as a man’s blood test has shown elevated prostate specific antigen (PSA) levels. Men start to worry as soon as they hear that. But out of every ten men with elevated PSA, only two have cancer – and of these two, only one has a carcinoma that will influence life expectancy, and one will have a “benign” cancer that does not require treatment. Still, both cancer patients would usually have surgery – with incontinence and impotence as frequent side effects. Before that, all ten men would have had to endure an uncomfortable digital rectal examination, and then 12 needles are inserted under ultrasound guidance into the tumor to take tissue samples, which is even more painful and can lead to complications. In 40 percent of all cases, the needles miss the suspect tissue, and also in 40 percent of cases they fail to reach the most aggressive part. The physician’s palpation examination is also unreliable: 70 percent of all carcinomas are not palpable.
And you can spare your patients all that?
Barentsz: Yes, thanks to the multiparametric MRI technology we’ve developed. As we like to say, “The urologist’s finger does not have eyes, but we have MRIs.”
What happens during a multiparametric MRI examination?
Barentsz: It has several steps. The latest equipment can create 3-dimensional (3D) color images in sharp focus. They provide us with not only anatomical, but also functional information. For example, we can use DWI, short for “diffusion weighted imaging,” to analyze the movement of water molecules, which is reduced in tumors. Choline and citrate concentrations also deviate from normal, as shown by spectroscopy. Then, a contrast agent can be used to measure perfusion. More blood flows through tumor tissue than through healthy tissue. Furthermore, another, newly developed nano-contrast agent can detect metastases down to a size of three millimeters. That’s revolutionary! It will be available exclusively in our department very soon.
What is the error rate?
Barentsz: Far less than ten percent. In the prostate, we can diagnose with 97 percent certainty that suspect tissue is not a significant life-threatening cancer – and in the lymph nodes with 95 percent certainty.
How many MRI machines do you have altogether?
Barentsz: We work with four Siemens MRI scanners. The newest is the MAGNETOM® Skyra 3 Tesla, which is my favorite and also the very best. Our Prime Minister, Mark Rutte, officially unveiled it when our diagnostic center opened in spring 2011. It does more than just take incredibly sharp 3D color images – it’s also very patient-friendly. There is a choice of colored lights to create a pleasant atmosphere in the MRI room, which is important because the patients have to go into a tunnel. The tunnel in this latest model is somewhat larger, with a diameter of 70 centimeters. So it can take in a patient who weighs 120 kilograms!
How long does the patient stay in the machine?
Barentsz: About half an hour. It can’t take much longer than that, because then the patient moves. And secondly, it would be too expensive. It’s well known that “time is money,” and a machine like this requires a significant investment. So it needs to be used as much as possible – even during evenings and weekends if necessary. And otherwise we couldn’t keep up with the influx of patients. The number of examinations we do here has increased tenfold since 2005, up to 2,500 in 2013.
Why aren’t these new methods used to treat prostate patients everywhere?
Barentsz: There are several barriers, the first of which is skepticism. We’re always hearing “That’s too good to be true” from our colleagues. Second, not every radiologist can simply switch over to this method. He must first be trained and gain experience. Third, politics has to be motivated, and fourth, insurance companies consider it too expensive, which is not a good argument! In the Netherlands, the number of prostate patients will soon increase from 10,000 per year at present to 17,000 per year due to increased life expectancy. MRI makes sustainable care possible. A quick, clear diagnosis spares the patient the current long, expensive, and often unnecessary treatments. There are fewer side effects and costs are lower. So the patient’s quality of life is better!
What does a diagnostic test at your center of excellence cost?
Barentsz: On the average, about 500 euros. And in most cases, the insurance companies do pay in the end. We take women’s breast check-ups as our model. I wonder, why don’t we have a “manogram”? Men should at least have a chance to be screened as soon as their PSA is elevated. Then they would have clear knowledge, and in most cases could go home reassured. Like the Russian patient today, who after years of uncertainty learned from us that he had only a chronically inflamed prostate, not a malignant carcinoma. After all, there are more men with prostate cancer than women with breast cancer – in the Netherlands it’s one out of every six men!
What are the next steps in conquering prostate tumors?
Barentsz: First, continue our persuasive efforts at conferences and symposia. In the meantime, after all, even the president of the European Association of Urology (EAU) has acknowledged that MRI can be helpful and could change the way urologists practice. Second, we are providing training in the new technology for radiologists and medical technicians in radiology at our reference center in Nijmegen. We currently have a young colleague from Hong Kong here. After two weeks, we provide support when they return home, by looking with them at the first 200 exams they have to interpret. We look over their shoulders by Internet, so to speak, double-checking and providing feedback. That’s how we ensure quality. Our “graduates” then set up many small “centers of excellence” at their end, which continue to be linked with us. In this way, in the long term, we’ll be able to build up a global network of MRI centers where men with high PSA levels can go to be screened. I wouldn’t rule out the possibility that we could stamp out cancer with early detection. That’s my dream. “Yes, we scan!”.
Is MRI technology used to treat prostate cancer as well as diagnose it?
Barentsz: Yes. To treat a malignant carcinoma, we immediately take a tissue sample in the MRI, but using only two needles. Because it is possible to reach the most aggressive part of the tumor with a needle, this needle can also be used in a controlled way to burn away the carcinoma with a laser or destroy it by freezing through cryo-ablation, without damaging the surrounding tissue. This is the future – and we are doing it now: We have already used cryo-treatment on 60 patients. We’ve even used laser treatment on an outpatient basis in four cases, where the carcinomas were small and easily accessible. For this purpose, we developed and patented a small MR-compatible robot-manipulator to guide the needle in the MRI system.
Kerstin Schweighöfer is a graduate of Henri Nannen Journalism School in Hamburg and studied Romance languages and literature, political science, and art history in Munich. Since 1990, she has been living in the Netherlands as a freelance foreign correspondent and works mainly for ARD radio broadcasters, Deutschlandfunk, the news magazine Focus, and Art magazine.