By Christie Long
It seems that as dogs get older, they get bumpier.
Veterinarians call bumps masses or tumors, and I always encourage my clients to bring in their dogs when they find a new mass. We can have a look at it together, measure it, record its exact location and consider a needle biopsy to determine if it might be malignant, or if it seems benign.
I tell my clients that “benign” is a loaded word. Dictionary.com defines benign, in the context of a mass or tumor, as “not malignant, self-limiting.” That’s good, right? Typically the answer is yes, but in the case of masses that grow on the eyelids of dogs, the tumor can be nonmalignant but still cause some serious problems.
The most common type of tumor that we find on the eyelids of dogs is called a Meibomian gland adenoma. Dogs and people have tiny glands called Meibomian glands that grow in the margin of the eyelids. The function of this gland is to secrete an oily component that makes up a portion of the tear film. Tumors that arise from the Meibomian gland are benign in that they don’t metastasize to other parts of the body, but they can definitely cause local complications for the dog.
The most common complication is excessive tear production in response to the irritation from the tumor rubbing on the cornea. This makes the dog uncomfortable, as you might imagine, but as the tumor grows it begins to really irritate the cornea. These tumors can become so large and rub so excessively on the cornea that they can cause an ulcer to develop on the surface of the cornea. Corneal ulcers are typically quite painful, and if this occurs the only way to definitively address the problem is to remove the tumor.
Sometimes small tumors can be debulked, which means snipping off the majority of the visible growth, and then using liquid nitrogen to freeze the margin of the eyelid so thoroughly as to kill any remaining tumor cells so that the growth does not return. This can typically be accomplished with the dog conscious but mildly sedated. But oftentimes these masses grow deep into the eyelid and need to be removed surgically. Most dogs will not tolerate this while awake, and because the use of a scalpel blade around the eye requires great precision, this is a procedure that must be done under general anesthesia.
Once the mass is removed with a wedge-shaped incision, the eyelid edges are brought together and sutured closed.
Very large masses can require skin grafts to ensure that there is not excessive tension on the eyelid. Healing is usually routine, but it is of paramount importance that the dog wear a snug-fitting Elizabethan collar to ensure that they cannot scratch at the eye and disrupt healing.
Christie Long is a veterinarian at the VCA Animal Hospital in Fort Collins, CO. Long left her job in software sales in 2000 to travel for 13 months. Along the way, she was touched by the plight of the animals she saw and somewhere in the Nepalese Himalayas she vowed to return to school to become a veterinarian. While she often finds end-of-life situations heart-wrenching, she considers herself blessed to be called upon as a trusted adviser to families during difficult times. Dr. Long’s family includes her husband and travel partner, Wiley, their son, Wiley IV, their dogs Pancake and Gizmo and cats Sneaky and Sidh.