Aging pets often get masses or growths under their skin and they are usually nothing to worry about. Still, it's an unpleasant surprise to find one when you are stroking your pet's fur. A mass is a lump that occurs under, inside, or on top of your pet's skin, and can be caused by an abnormal growth of cells, immune reactions, hormonal changes, or a cyst. Some common masses that occur on pets include benign tumors such as lipomas, skin tags, or cysts. Less often, the mass is malignant such as with mammary tumors, squamous cell carcinomas, osteosarcomas, mast cell tumors, and lymphomas.

What to Do if Your Pet Has a Mass

Even though most lumps you find on your pet will not need treatment unless they become irritated or inflamed, even the smallest chance of cancer is too much to ignore. So, it's important to investigate the cause of any mass you find on your pet. Here are some steps you should take when you notice a growth in your pet.

• Identify the location. Masses that are smaller in size are sometimes difficult to re-locate after their initial discovery, especially if your pet has longer fur. Therefore, it is recommended to shave the area around the mass and take a picture to help determine if the mass is changing rapidly, slowly, or not at all.
• Measure the mass. Measure the mass as soon as you discover it and continue to measure it at regular intervals to help see how fast it is growing, if at all.
• Monitor your pet. Watch to see if the mass is bothering your pet or if they are experiencing any other problems. Take note of whether they scratch the area, if the area seems painful or tender to the touch, and if the area oozes or bleeds. Observe whether your pet is eating, drinking, and behaving normally as well.
• Schedule a vet visit. If your pet's mass is malignant, time is essential. Early detection improves your chances for a happy outcome if your pet does have a cancerous growth. Bring any pictures, measurements, and observations you have noted to your pet's appointment.

Mass Diagnosis

At your pet's appointment, your veterinarian will determine what the mass is made of using a type of biopsy called fine needle aspiration. The process requires that a needle be inserted into your pet's mass so that a cell sample may be taken from it. Your veterinarian can determine whether it is cancerous by looking at it under a microscope.

If a malignant tumor is discovered, your vet may advise "staging" your pet, which could entail a surgical biopsy, x-rays, ultrasound, or MRI to see if cancer has spread to other parts of their body before surgical removal. If cancer has not spread from the mass, your vet will want to remove it as quickly as possible before the mass has a chance to spread. If cancer has spread, simply removing the mass wouldn't cure cancer, so other treatment options such as chemotherapy and radiation, or even experimental treatments and alternative therapies may be explored in addition to mass removal.

Mass Removal

If your pet only needs mass removal, that is very good news. It means that, with surgery, aftercare, and close observation, your pet has an excellent chance at a happy outcome. 

Your pet will be anesthetized for their mass removal surgery. While your pet is under anesthesia, their oxygen levels, pulse, blood pressure, respiration, heart rate, and body temperature will be closely monitored.

The tumorous mass may be removed by electrocautery, a surgical procedure that uses an electric current to heat a metal wire electrode that destroys abnormal tissue and can be used to control bleeding during surgery. Once the tumorous tissue is removed, the incision will be closed with sutures that will either be absorbed by your pet's body as they heal or have to be removed by your vet at a later date. 

Veterinarians often recommend that the mass be submitted to a diagnostic laboratory after it is removed for further testing that can identify the exact type of cancer that caused the mass and determine the margins of mass removal, which indicate whether the mass was completely removed during surgery. Your vet may make further treatment recommendations based on the laboratory results. 

Mass Removal Aftercare

It's typical for your pet to feel a little lethargic for a day or two after surgery. Call your veterinarian if your dog or cat appears to be in discomfort. They might be able to recommend a medication to lessen the pain.

In order to ensure that your pet heals and recovers as quickly as possible after the mass removal procedure, it is imperative that you heed all your veterinarian's aftercare instructions. Giving your recovering pet a place to relax, using an Elizabethan collar if necessary, and preventing them from climbing, jumping, and doing intense activities following the surgery will help aid their recovery. Some issues to watch for post-surgery include:

• Swelling or bleeding around the wound.
• Licking the wound continuously.
• Redness, inflammation, and heat around the wound.

If you notice any of these issues or have any other concerns about how your pet is recovering, seek further advice from your veterinarian.