Tiny Beads Cause a Revolution in Cancer Treatment in Cats
Around 2008, I came across a new option to complement cancer surgery. Results have been impressive. Until then, chemotherapy and radiation therapy were the two main solutions offered after removal of cancerous tumors, just like in people. Both treatments may cause side-effects, and they can cost thousands of dollars.
About the chemo beads
Chemo beads cost a fraction of any other option. 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 with an IV in our canine cancer patients.
Unfortunately, cisplatin can be deadly in cats, but by including a minuscule dose in the beads, veterinarians are now able to eliminate the former side-effects.
The beads measure 3 mm in diameter, or about 1 tenth of an inch.
The limitations of the chemo beads
Although cisplatin beads are often effective at preventing or slowing the cancer from coming back, they do not prevent spreading (metastasis), e.g. to the lungs. Fortunately, 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 edges (margins) are questionable. Implanting beads after the surgery (e.g. after the biopsy report reveals imperfect edges) 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 risks, 6 beads are usually the most used in cats. 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 deadly in cats, I have not observed or heard of general side-effects after bead placement.