Breast Cancer Patient Karen Metz Talks About Her Treatment with Varian's Real-time Position Management (RPM) Respiratory Gating System.
Karen Metz is a 41-year-old woman living in Greenbrae, California. She owns and works at Marina Morrison Ltd., a bridal salon in San Francisco, California. In August 2003, Karen was diagnosed with cancer of her left breast. Working with her doctor, she chose to be treated with a lumpectomy, followed by chemotherapy and radiation. Meanwhile, Dr. Francine Halberg, of the Marin Cancer Institute at Marin General Hospital in Greenbrae, California, had begun using the RPM™ Respiratory Gating system from Varian Medical Systems to minimize the damage to heart and lung tissue that can sometimes occur during radiation treatment for left-sided breast cancer. Karen was found to be a prime candidate for this new approach to radiation therapy that improves targeting and spares vital healthy tissues.
RPM Respiratory Gating
Varian’s RPM Respiratory Gating enables clinicians like Dr. Halberg to compensate for normal respiratory motion during radiation treatments. RPM uses an infrared camera to track a passive marker block placed on the patient’s chest or abdomen. The system then converts the tracked motion into a respiratory waveform that shows the patient’s normal breathing pattern. Dr. Halberg then selected the optimal phase of Karen’s breathing cycle, when the breast tissue to be irradiated was farthest from the heart, and programmed the system to deliver radiation only at that recurring point each time Karen took a breath.
Dr. Halberg began by evaluating Karen to see if she would benefit from respiratory gating. Using fluoroscopy, a form of time-lapse X-ray imaging, she checked to see if taking a deep breath moved Karen’s breast up and away from her heart without putting any extra lung tissue at risk.
According to Dr. Halberg, only certain women benefit from respiratory gating. It turns out to be a function of breast geometry. While not all patients will realize a benefit from respiratory gating, there are some for whom it makes an enormous difference. Karen was one.
An Interview with Karen
When/how did you discover you had cancer?
I discovered a small knot in my left breast late in 2002, but it wasn’t causing a problem and my mammogram came back clean. However, when it was still there on August 20, 2003, my doctor, a women’s health specialist in San Francisco, performed a fine needle biopsy. On August 26 she told me that the biopsy indicated cancer and that I would need to schedule a core needle biopsy. The results of the core biopsy showed that the tumor was over two centimeters and definitely invasive, but still at an early stage. The doctor outlined the possible next steps — that I would have a lumpectomy, and depending upon the results of the lumpectomy, whether the treatment would be radiation and/or chemotherapy and/or hormone therapy.
What was your reaction?
At this point, I was relieved to have some facts that I could react against and not be wondering all the time what it was. My doctor explained that she would remove the tumor, and then refer me to other doctors, who would complete the treatment. She outlined the types of treatment and the timelines involved.
What did you do?
I must have read every book and visited every web site on breast cancer.
What happened next?
I underwent the lumpectomy and a biopsy on September 12. The lumpectomy revealed that the tumor was actually 1.5 centimeters, and the biopsy confirmed that the cancer had not spread to my lymph nodes. The next step was a course of chemotherapy followed by radiation. I was concerned about the side effects associated with chemotherapy — loss of hair, nausea, fatigue, and so on. But I was fairly young and figured that this would be the optimum time to withstand those problems rather than run the risk of leaving cancer cells floating around somewhere in my body.
On January 15, 2004, three weeks after I completed my chemotherapy treatment, I visited with Dr. Francine Halberg at the Marin Cancer Institute in Greenbrae, California to discuss my radiation therapy. I chose Marin Cancer Institute because not only was it so close that I could walk there from my house, but I also liked the set-up. The atmosphere was bright and the people were warm.
What did Dr. Halberg tell you about Real-Time Position Management (RPM) Respiratory Gating?
Dr. Halberg told me that they were pioneering a program called respiratory gating and that it could help my radiation treatment. She explained that as you breathe in and out your chest goes up and down and that your heart and lungs can be exposed to the radiation at that time. Dr. Halberg told me that the respiratory gating works in conjunction with my breathing and only delivers the radiation at the point where it treats the breast and does not affect the heart and lungs.
What did you think at the time?
It made good sense to me, so I decided to go ahead.
What other treatment options were you given?
None. When Dr. Halberg got my films back she told me that respiratory gating would really help me because of my particular breathing pattern. It seemed that when I took a deep breath, my heart moved out of the radiation field.
Did you do any research about RPM or other options?
No. I was done with my research and I trusted Dr. Halberg's judgment.
Describe your RPM experience
How was the procedure described?
Dr. Halberg explained that the actual treatment would take slightly longer and that I would have to learn a particular breathing pattern -- to inhale and hold at certain times during the treatment. I had concentrated so much on getting through the chemo that I hadn’t really thought about what actual radiation therapy was like: that there would be a set up; that I would be alone in the room while the radiation was delivered; and that it would be a very different experience from chemo where all of the patients sat in a row in the same room. I thought radiation treatment would be similar to a mammogram. It was only when we did the simulation that I realized that radiation was a much bigger deal than I had anticipated. So I was intimidated at first by the room and the machine and felt very vulnerable.
When did the treatment start and end?
Treatment began on January 29 and ended on March 16, 2004.
How many treatments did you have in that time?
33 treatments.
What were they like? What did you have to do? Did you find it difficult?
The treatments themselves were painless, but I had to learn a special breathing pattern. I had to take consistent deep breaths and hold my breath for about 30 seconds at a specific point in my breathing cycle. This meant I had to regulate my breathing so I always had the same amount of air in and out. It was hard to do on the first day, but I finally got it right, and after I acquired muscle memory everything was much easier. They placed little blocks on my chest that they used as markers to determine the levels to which I inhaled and exhaled so they could efficiently track my breathing pattern.
Was it painful?
No.
Were there any side effects?
Dr. Halberg mentioned that there would be darkening of my skin, some dryness and fatigue at the end. My skin was darker and I received some lotion for the dryness. The fatigue didn’t really affect me until two weeks after the last treatment.
Are you happy with your decision?
Yes.
How do you feel about your doctor and staff?
They were very professional and attentive. They had a lot of respect for each other and for their patients.
How are you doing now?
Okay. I recently had a check up that came back clean. I’m back to work full-time now and resuming my life.
What is your advice to others?
Read as much as you can. Trust your instincts. If there are no side effects and it works for you, then I would definitely recommend respiratory gating.
