Frequently Asked Questions
While receiving proton therapy for Prostate Cancer at the M.D. Anderson Cancer Center Proton Therapy Center
1. What foods can I eat?
Included with your introduction information packet is a list of food that are not recommended, because they may cause gas. Any food that creates gas in your intestines and colon may alter the precise position of the prostate during treatment. For this reason one must try to limit gas generation. If gas does occur the radiotherapy technician may use the new version of the endorectal balloon to relieve the gas pressure before treatment. Have a feast of your favorite food on Friday and Saturday nights! Beano and GasX have variable results, so do not rely on these over the counter remedies.
Nuts or foods that can irritate your lower tract (the rectum) and probably should be avoided. One patient from Loma Linda who went into an emergency room for rectal bleeding was particularly fond of Special K cereal bars and only by chance did he mention this to the emergency room clinician. She being knowledgeable picked up on this, and the patient was told to avoid foods with sharp edges. But don’t avoid all fibers and that will cause another problem, constipation or hard stools. (radiation effects on the bowel area ) I think Dr. Lee would recommend that you don’t make any drastic changes to your diet and relax. This treatment works. (see the section on Nutrition for more information).
2. Can I take my vitamins and antioxidants?
There are vitamins and there are vitamins! The doctors agree that the RDA(required daily amount) is reasonable for one to consume during proton treatment. However the doctors are opposed to high potency anti-oxidants as they can reduce the effect of the proton treatment and limit the potential to cure your cancer. The reason for this is the proton disintegrates at its terminus in the tumor and produces ions which are positively charged particles that are in fact “oxidants”. If you are taking fish oils and flax oils as recommended by your heart doctor you should discuss this with your proton oncologist doctor. After treatment is concluded you may resume your normal intake of vitamins and anti-oxidants. Ask your oncologist about the effects natural herbs that are used to enhance sexual desire/performance. It’s been known to elevate the PSA readings taken during the quarterly follow up tests during the first year after treatment. Also known to depress PSA is the herb saw palmetto. After treatment and in recovery you want the PSA levels measured during check up to be truly representative of what’s going on.
3. What is the importance of water intake before treatment and during treatment?
Water in the bladder raises the bladder off the prostate so that radiation exposure to the bladder is reduced. It is important to have a nearly full bladder during your treatment and you will carry a card that is prepared from the result of your simulation that stipulates the amount of water you need to have in your bladder during treatment. There are two numbers on the your patient card with the lower number representing 80% of bladder capacity and the higher number representing 100% measureable balder capacity. The doctors want you to be within this range and not less than the lower or higher than the upper limit. Each day before treatment your radiotherapist will use a hand-held sonogram device to check your water level by placing the device on your lower abdomen and taking several measures to determine your water status. If you do not have adequate water in your bladder you will have to wait and drink water until you meet the minimum level. It usually takes about 20 minutes for water to percolate into the bladder if you are already hydrated. If you have been outdoors and sweating it may take a lot of water intake before your bladder will start to fill. Some patients on blood pressure regulation will have difficulty with bladder filling.
4. How am I to be assured of the correct position in the proton unit?
On the patient card that is provided when you checked in to the front desk on your first day of treatment the therapist will hand write 3 numbers. Two of the numbers relate to your bladder capacity. The third number is the reference for setting your positioning blocks coupled with the lines drawn on your legs to properly position your body before treatment. An x-ray is taken each time you enter the proton unit to align the table you are on to precisely position your body comparing to a digital image that locates your prostate relative to your hip bones and ensures accuracy during the treatment. Starting in late 2009, the doctors at the proton center started inserting two markers called fiduciaries in your prostate gland to speed up the alignment process. These are very small carbon seeds that show up on the x-ray along with a marker visible on the balloon tip.
5. What is the balloon and what does it do?
There are two balloons used in the treatment process. One is inserted in to your rectum during the MRI to evaluate your physiology. The second balloon is inserted and filled with water to expand the rectum, elevate the bladder and reduce exposure of non prostate tissue to radiation. The balloon which contains about 100 cc of water also helps firmly position the prostate into/against the pelvic bone to provide consistent location for targeting radiation. MD Anderson is very careful and precise about measuring the water levels and positioning the balloon.
6. Is it allowable to have intercourse?
If you do not experience any pain that is not too discomforting then, yes, go ahead. Your partner will not glow in the dark afterwards.
7. I have hemorrhoids, should I be concerned?
This can be a problem depending upon the severity of your hemorrhoids and where they are located. The doctors allow use of a hemorrhoid preparation in the morning and evenings but not just before the treatment. The insertion and withdrawal of the balloon each day can cause some irritation but generally it is not a painful or unbearable process.
8. Will I be able to discuss my progress with my doctor frequently?
Yes each week all the doctors hold a “see” to communicate with the patient and to enquire if there are any complications developing during treatment. The excellent nurses are another good source for help and to answer your questions.
9. What symptoms will I experience during treatment?
Symptoms vary with individuals and generally most patients will have some additional frequency and difficulty urinating. There may be a burning sensation during urination but not severe. Some patients may have a case of diarrhea. Symptoms come and go but the usual case is that nothing is really painful or unbearable. Ibuprofen may reduce the burning and irritation providing relief for urination by reducing inflammation in the urethra. The doctors may offer Flomax for urinary improvement and suppositories for diarrhea.
10. Since the therapy is so precise will the proton beam kill only the malignant cells?
The dosimetrist and your oncologist develop a radiation plan that will deliver a maximum dose of radiation to the tumorous area. They also make provisions to expose the remainder of the prostate gland and the seminal vesicles outside of the prostate capsule to some level of radiation in order to catch any other areas that may be involved. He also models those lines to reduce exposing other vital areas close to the prostate gland. See the slide show for a typical isoplot of the radiation levels. These are done with a complex computer program using images and density data collected during your simulation run.
11. Can I feel the proton beam?
No. The beam is on for approximately 40 seconds and most patients continue in their normal activity. Some who are working in Houston stop off at the Center before going to work and some continue physical recreation activity such as golf or tennis. One man who received two treatments in the same day 8 hours apart and played 18 holes of golf between treatment appointments. The only evidence is you have is two sun tan spots that develop on either hip over 8 weeks of treatment and eventually disappear. During your weekly “see” the doctor will examine your spots.