Tiny Beads Cause a Revolution in Cancer Treatment in Dogs
New options for cancer treatments in dogs don’t exactly occur every day. Around 2008, I heard of a new option to complement cancer surgery. So far, my results using this option have been very impressive.
Until recently, my “follow up” treatment after removal of cancerous tumors included chemotherapy and radiation therapy, just like in people. Both options have potential side-effects, and their cost can reach thousands of dollars, that’s why I’m excited about the new option of chemo beads.
About chemo beads
Chemo beads cost a fraction of any other option. Using chemo beads, veterinarians are now able to place tiny cisplatin-impregnated beads around the tumor site. Cisplatin is then slowly released from the beads, which are reabsorbed by the body over 4-6 weeks. Cisplatin is a common chemo drug, normally used IV in our canine cancer patients. One of the most common side-effects of this method is kidney damage. Now, by including a minuscule dose of cisplatin in the beads (instead of IV), we are able to drastically decrease, if not eliminate, the side-effects.
The beads measure 3 mm in diameter, or about 1 tenth of an inch.
The limitations of chemo beads
Although cisplatin beads seem to prevent the cancer from coming back, they do not prevent spreading (metastasis), e.g. to the lungs. Luckily, some of these tumors do not spread readily to begin with.
When are the beads placed?
The best time to place the beads is at the time of surgery, when we know exactly where the tumor was and where cancer-free “margins” (i.e. edges) are questionable. Implanting beads after the surgery (e.g. after the biopsy report reveals narrow margins) has 3 drawbacks:
- It is difficult to know where margins were
- It requires another surgery under anesthesia
- There are additional costs.
The number of beads varies with the size of the tumor. They are typically placed every 1-2 cm. However, to decrease the risk of complications, we try to limit the number of beads to 15 in dogs. This means that the tumor can’t be too big, if the patient is to be a good candidate.
Side-effects of chemo beads
Side-effects are rare and typically local. They occasionally include swelling, irritation and skin drainage. Although IV cisplatin is toxic to the kidneys in dogs, general side-effects have not been observed after bead placement in dogs.
Chemo bead safety for people
Ironically, chemo drugs can cause cancer. Therefore, the pet parent should not touch any drainage with their bare hands. It is important to wear disposable, single-use gloves to clean any oozing. The patient should wear an E collar 24/7, and should be separated from other pets.