I am scheduled to have the first of four PRRT treatments on Friday, March 1st. Today, February 26, I had a meeting to learn about it and the rules for me and to have the blood tests which will be the benchmark for the blood tests that I will have every two weeks for the next none months.
First, I have done a little explanation of PRRT in this previous post. Here is another attempt at clarification:
PRRT – Peptide Receptor Radionuclide Therapy
- P – Peptide: In the case of this treatment the peptide is a somatostatin analog similar to octreotide. Somatostatin is an endocrine hormone made by our own bodies. Octreotide is a commercially made chemical very similar to somatostatin that many people with NETs (like me) have injected into their rear ends every month or more
peptide /pep·tide/ (pep´tīd) (pep´tid) any of a class of compounds of low molecular weight that yield two or more amino acids on hydrolysis; known as di-, tri-, tetra-, (etc.) peptides, depending on the number of amino acids in the molecule. Peptides form the constituent parts of proteins.https://medical-dictionary.thefreedictionary.com/peptide
- R – Receptor: Neuroendocrine tumors have (or express) receptors on their surface that attempt to bind with somatostatin as it passes by in the blood stream. Unfortunately, only 80% of the receptors are active, so any particular patient may not be a good candidate for PRRT if their receptors are not active. Also, even if most of a patients tumors have active receptors, they may not all be active. PRRT is said to be 75% likely to have positive effect.
- R – Radionuclide: A chemical substance, called an isotope, that exhibits radioactivity. In the GA-68 scans which I have written about, Gallium-68 is the isotope. It is not radioactive enough to worry much about damage to the patient. In PRRT the radionuclide is Lutetium-177. This is strong enough to damage the tumor cells but not to damage the patient, if controlled. The brand name of the Lutetium-177 and octreotide combination is LUTATHERA distributed by: Advanced Accelerator Applications USA, Inc., NY 07041
- T – Therapy: This therapy directly targets the molecules of the tumors. Because it works over the whole body, can be ideal for someone like me who has tumors in the liver, the pancreas, behind my eyes in the skull, in three vertebrae and in my abdominal wall. This will probably not eradicate the disease but the goal is to shrink the tumors and be stable (progression free) for three to four years (average). If or when progression occurs it can be repeated.
There are many places to look for more detail. Try these:
My informational meeting today
It was more than information. NOTE: Bear in mind that everything below will be particular to Rocky Mountain Cancer Center (RMCC), Dr. Liu’s offices. Not all clinics will have identical procedures.
The PRRT will be done four times, once every eight weeks. Today’s blood lab tests will form a benchmark to compare with lab tests that will be done every two weeks for nine months! This is to closely monitor my blood cell count to make sure that the radiation is not making it too low.
On Thursday, the day before PRRT, I will go to RMCC and they will insert a PICC Line. This is a long flexible IV tube running through my vein to a near the intake valve of my heart. I have been told that most clinics do not use a PICC line, they use standard IVs instead. The PICC Line will be removed after the treatment is given on Friday.
On Friday, the day of treatment, the whole process should take 5 or 6 hours.
- 1 hour before the LUTATHERA, I will be given a short acting anti-nausea medication and an antacid through the PICC. then a longterm anti-nausea through the IV. These are because the next step is known to cause nausea in many patients. I am told it is better now than it used to be!
- At this an infusion of amino acids will begin. The purpose of these amino acids is to protect the kidneys from radiation. I am told that our kidneys are among the most sensitive organs to radiation yet in this therapy, they must clean it all out of the bloodstream ultimately.
- The LUTATHERA infusion will start 30 to 45 minutes after the amino acids have started and will last about 40 minutes. Then there will be a saline flush.
- The rest of the amino acid infusion will be finished and the PICC removed.
- After the above process people must stay a designated distance from the patient. You are radioactive.
- As long as all has gone well, the patient is released and can drive themselves home, if they wish.
- Avoid close contact with people. Try to keep a distance of 3 feet for 3 days. During that time avoid public places.
- Limit contact (3 feet) with children for 14 days.
- For the first two or three days after treatment bedding, pajamas, clothing must be washed separately from other people’s laundry. They should be washed two or three times.
- For any air travel, you must keep a discharge letter with you for at least 3 months after treatment.
- Other precautions.
Possible Side Effects (None are very common)
- Hair loss
- Weight loss
- many more
- Interestingly, many of the listed side effects are the same as the side effects of Sandostatin (octreotide).
I asked if there was anything that could occur long term. PRRT has been blamed for leukemia in a few cases. Only one case was seen at RMCC a year after PRRT was given at a different clinic. There was no way to determine whether that patient would have developed leukemia anyway.
I will attempt to blog my personal experience with the therapy this weekend.