Lumps & Bumps

Lumps & Bumps: What Can We Really Tell by Feeling Them?

If you have a dog or cat, chances are you’ve eventually found a lump or bump somewhere on their body. And one of the first things I hear from concerned pet parents is:

“Can you tell what it is just by feeling it?”

The short answer is: sometimes we can get clues—but we cannot determine what type of cells are present simply by putting our hands on it.

What Can We Learn by Feeling a Mass?

When I examine a lump, there are several characteristics I pay attention to:

Size – How large is it? Has it changed in size?

Location – Where is it located? Certain types of masses are more common in particular areas of the body.

Consistency – Is it soft, firm, rubbery, or fluid-filled?

Mobility or attachment – Can I easily move the mass underneath the skin, or does it seem firmly attached to deeper tissues?

Margins – Does it feel well-defined, or are the edges difficult to distinguish?

Pain – Is the area painful when manipulated?

Skin involvement – Is the mass beneath normal skin, attached to the skin, ulcerated, inflamed, or causing changes to the surrounding tissue?

All of these characteristics can give me valuable information and help determine how concerned I should be.

For example, a small, soft, freely movable mass may have a very different feel from a firm, irregular mass that appears fixed to underlying tissues.

But here is the important part: A mass that feels benign does not necessarily mean it is benign. And a mass that feels concerning doesn’t automatically mean it is cancer.

Our Hands Can’t Identify the Cells

This is where diagnostics become extremely important.

When I palpate a mass, I am evaluating its physical characteristics. I am not actually seeing the individual cells that make up that mass.

Two completely different types of masses can sometimes feel remarkably similar.

This is why I often recommend a fine-needle aspirate (FNA).

What Is an FNA?

An FNA involves inserting a small needle into the mass and collecting cells that can then be placed onto microscope slides.

The procedure is generally quick and minimally invasive, and many masses can be sampled without sedation.

Sometimes I can evaluate those slides in the clinic and obtain a good idea of what we are dealing with. In other cases, I will recommend sending the slides to a veterinary clinical pathologist for a more thorough evaluation.

This can help determine whether the sample contains:

* Normal or reactive cells

* Inflammatory cells

* Fat cells

* Infectious organisms

* Benign tumor cells

* Malignant cells

* Or a cell population that requires additional investigation

Sometimes the FNA Is Only the Beginning

There are situations where an FNA does not give us a definitive answer.

Some tumors don’t exfoliate well, meaning they don’t release many diagnostic cells into the needle sample. Other masses may have areas of necrosis, inflammation, or mixed cell populations that make interpretation more difficult.

Depending on what we find, additional testing may be recommended.

One example is PARR (PCR for Antigen Receptor Rearrangement). This is a specialized molecular test that can sometimes help determine whether lymphoid cells represent a clonal population, which can be useful when evaluating suspected lymphoma or distinguishing certain lymphoid proliferations.

Other diagnostic options may include additional cytology testing, special stains, immunocytochemistry, flow cytometry, or ultimately a biopsy/histopathology, where an actual piece or the entirety of the mass is examined by a pathologist.

“But It’s Been There for Years…”

This is another common scenario.

A lump that has been present for a long time may certainly be less concerning than one that suddenly appeared and is rapidly growing—but time alone doesn’t tell us what the mass is.

Some tumors grow slowly. Others can remain relatively unchanged for quite a while before becoming problematic.

Likewise, a lump that suddenly changes in size, becomes firm, develops an ulcer, starts bleeding, or becomes painful deserves particular attention.

When Should You Have That Lump Checked?

My general rule is:

If you find a new lump, let your veterinarian know about it.

We can measure it, document its location, evaluate its characteristics, and determine whether an FNA or other diagnostic testing is appropriate.

I especially encourage evaluation if a mass:

Is growing or changing

Is firm or fixed in place

Becomes painful

Changes the appearance of the skin

Bleeds or ulcerates

Appears suddenly

Is located in an area where a tumor could have significant consequences

Or simply makes you uncomfortable not knowing what it is

Don’t Guess—Sample It!

One of the most valuable things we can do as veterinarians is replace guessing with information.

Our hands can tell us a lot about a lump—but they cannot tell us exactly which cells are hiding inside it.

Feel it. Measure it. Monitor it. And when appropriate, sample it.

Because when it comes to lumps and bumps, knowing what we’re dealing with allows us to make better decisions about what comes next.

Early investigation can mean earlier answers, earlier treatment, and more options for your pet.

Cassie Sheehan, DVM, CVA, CVMMP Floral City Animal Clinic, Inverness Fl.

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Note.. There is no way to diagnose the vast majority of lumps on appearance only. A lump is a lump is a lump. A N Y lump deserves to be examined cytologically.A needle is inserted, some cells are removed, stained and examined microscopically. The evaluation can either be done by a vet with experience doing so, or sent to a pathologist. The cells can often provide a diagnosis or guide us into knowing how to proceed – biopsy (to better identify if cytology diagnosis),remove,ignore. Cytology is used to decide if the mass is likely not malignant, or if additional diagnostics or removal is indicated, and how aggressively it should be excised (how big/deep the incision should be).

There are few masses/tumors that can be diagnosed by just the appearance or how it feels. Some lumps look boring and are actually evil: some look evil but are benign. And so many masses look and feel the same. If cytology doesn’t provide a diagnosis, biopsy is advised. There is no way to diagnose the vast majority of lumps on appearance only. By Dr. Kathy Morris-Stilwell

**The Vet Corner groups encourage members to establish a relationship with their local veterinarian, don’t wait until an emergency.**