Innovative Cryotherapy for Canine Nasal Tumors

Medical articles

The most common symptoms of nasal tumors in dogs are snorting sounds while breathing, nasal discharge, and nosebleeds.

Typical treatment for nasal tumors involves radiation:

  • 16 radiation treatments over three weeks

  • Each one requiring anesthesia

The mean survival time, after radiation, is 12-14 months. Side-effects of radiation treatments often impact a dog’s eyes and mouth as well.

New Less Invasive Option Being Tested

Michele Steffey, DVM, Dipl. ACVS, assistant professor of small animal surgery at University of California-Davis, School of Veterinary Medicine, is testing a new treatment called “transnare cryoablation.”

Essentially, she is using extreme cold to freeze and remove the tumor tissue.

Steffey explains, “The cryoprobe is basically a large needle that is closed at the tip. Inert gasses – argon and helium – are cycled through the cryoprobe to control the temperature and vented back through the system, so the patient is never directly exposed to the gasses. The argon is the gas that causes the drop in temperature around the probe due to the expansion of the gas (Joule-Thompson effect) within the probe. We take the temperature down to about -60 to -80 degrees Celsius to kill the tumor.”

Transnare cryoablation is considered less invasive that traditional treatments because it does not require any incisions. In addition, Steffey’s team can make several passes with the freezing probe while the pet is under anesthesia just once. Depending upon the specific case, some dogs may require additional sessions later.

For example, a 9-year-old chocolate Lab named Barkely had been in treatment for adenocarcinoma for a year when he became a patient of Steffey’s. The good news is that nasal adenocarcinoma often grows only where it begins without rapidly spreading to other areas of the body, such as the lungs or lymph nodes.

Barkely’s tumor stretched from the tip of his nose all the way to the back of his nasal cavity. While Barkely had some invasion from the left to the right side of his nose, the tumor had not broken through the cribriform plate, a bone that separates the nasal cavity from the brain.

In March 2013, while under anesthesia, Barkely received four consecutive treatments with the cryoprobe in about 45 minutes. He had a few nosebleeds afterwards, but Steffey says that’s to be expected.

Barkely’s four-month recheck CT scan showed no evidence of nasal tumor regrowth and no evidence that the cancer has spread to his lungs or lymph nodes.

The clinical trials of this new procedure are just beginning, so it’s hard to know how long these results may last. So far, things look promising.

Steffey says, “All types of nasal tumors may be enrolled in the study, and we will follow their outcome in order to eventually make more specific recommendations as needed. However, just like other local therapies for cancer (radiation, surgery), there may be anatomic or other limitations to safe administration of the treatment in an individual patient, and that decision can only be made on a case-by-case basis.”

Have you enrolled your pet in experimental treatments?

This is brand-new stuff. Have you ever allowed something new to be tested on one of your pets? Would you do it, if you had the chance?