Cytology Dog Lump: Causes Types and Treatment

A dog lump can be a concerning discovery, especially if you're not sure what it is or where it came from. Most lumps on dogs are benign, meaning they're not cancerous.

Some common types of benign lumps on dogs include lipomas, which are fatty tumors that can appear anywhere on the body. They're usually soft to the touch and can be moved slightly.

Cysts are another type of lump that can occur on dogs. They're typically filled with a thick, cheesy liquid and can be painful to the touch.

Intriguing read: Benign Lump on Dog

Dogs can develop various types of lumps, but most are benign and not cancerous. Lipomas, for example, are benign fat tumors that are common in overweight dogs and more likely to develop as a dog ages.

Some breeds, such as Labrador Retrievers, Doberman Pinchers, Miniature Schnauzers, Cocker Spaniels, Dachshunds, Golden Retrievers, and Weimaraners, are prone to lipomas. Benign cysts, like inclusion cysts, can also form on a dog's skin.

Benign epithelial neoplasms, such as sebaceous adenomas, can occur anywhere on a dog's body but often appear on the head.

Benign cysts can be a type of lump that forms in a dog's skin or organs. They are usually benign and don't need to be removed immediately, but their location and impact on the dog's health should be considered.

A classic dermal inclusion cyst is a type of benign cyst that's lined by several layers of squamous epithelium and filled with keratinous debris. When aspirated, these cysts yield little more than fully keratinized squames.

Inclusion cysts can rupture, causing a marked foreign body inflammatory response in the dermis. This can lead to a mixed inflammatory response, keratinized squames, and cholesterol crystals cytologically.

Sialocele is another type of benign cyst that forms by obstruction of a salivary duct or gland. It's seen as a swelling on the neck or face and can cause secondary abnormalities like protrusion of the eyeball.

Aspirates from sialoceles are relatively low in cellularity and contain a uniform population of large foamy macrophages, many of which contain black pigment granules.

Lipomas are extremely common growths that can appear on your dog's skin. They are benign, noncancerous tumors that grow from fat cells.

Most lipomas are found in the tissue layers below a dog's skin, and they are more common in overweight dogs and those that are aging. Labrador Retrievers, Doberman Pinchers, Miniature Schnauzers, Cocker Spaniels, Dachshunds, Golden Retrievers, and Weimaraners develop more than their fair share of lipomas.

The main symptom of a lipoma is a lump or mass that you can feel just underneath your dog's skin. This lump can be round, oval, or somewhat irregular and more bulbous in shape.

Lipomas can be found in just about any spot on (or in) a dog, but most are found on the pet's abdomen and chest. Many lipomas are also found on a dog's legs, but no location is off limits, including the organs inside a dog's body.

Benign tumors like lipomas may not need to be removed immediately, but their location on your pet's body should be considered. Will an increase in growth in this location prevent successful surgery? Is the mass causing pain, irritation, secondary bleeding or infection?

For another approach, see: Skin Cancer Lump on Dog

Your veterinarian may recommend a noninvasive test known as a fine-needle aspirate and cytology exam to get an accurate diagnosis of the mass. This is a diagnostic procedure where a needle is inserted into the mass for a sampling of cells.

Most lipomas require only monitoring, as they pose no threat to your pup unless they are uncomfortably large or in an awkward location. The growth of most lipomas is slow, alleviating the pressure to make a hasty decision about surgical removal.

To determine if a lump on your dog is cancerous, your veterinarian will perform a fine-needle aspirate and cytology exam, which involves inserting a needle into the mass to collect cells.

This quick and safe test allows your veterinarian to examine the cells under a microscope to identify specific cell patterns or structures, which may provide information about the process or tissue type present.

Inadequately cellular samples may reflect poor sampling technique, so it's essential to ensure that the sample quality is confirmed before making any conclusions.

Typically, lipomas have oily material and fat cells that are easy to identify under the microscope, but taking a biopsy with a larger tissue size is essential to confirm that the mass is a lipoma.

No one can tell what a lump is just by feeling, and "watching and waiting" is not a good idea; get the masses aspirated to determine what they are.

With early diagnosis, less treatment will likely be required, and a smaller surgery may be curative, making it a better prognosis for your dog.

Principal cell types determine classification, and evaluation for underlying causes, such as infectious or noninfectious etiologies, is warranted to make an accurate diagnosis.

Overtly malignant neoplasms demonstrate specific structural changes that can be observed by light microscopy at high-power magnification, representing the basis of cytologic criteria of malignancy.

In fact, most tumors are benign, not cancerous, so it's essential to have those lumps and bumps aspirated to determine what they are.

Most lipomas in dogs require only monitoring, as they pose no threat unless they're uncomfortably large or in an awkward location.

It's essential to have an accurate diagnosis and to know that the mass is indeed a lipoma. Slow-growing lipomas can be monitored without the need for surgical removal.

If you and your veterinarian opt for a conservative approach of monitoring your dog's lipoma, pay careful attention to monitoring the size and growth rate of the lipoma. Record the size at least every six months and document it with photos and measurements.

Lipoma growth is gradual, and many lipomas have been known to sneak up in size until they're as big as a basketball or even larger. Maintaining your dog at a proper weight will usually help control the growth of lipomas and prevent future ones.

Surgical removal may be necessary for lipomas that are larger or invasive into surrounding tissue, or those that are growing rapidly. Some lipomas may also require surgical removal if they become irritated or cause discomfort for your dog.

Related reading: Dog Lump Removal Surgery Cost

The first approach to diagnosing a cytology dog lump is through fine-needle aspiration, which involves using a thin needle to collect a sample of cells from the lump for examination.

Fine-needle aspiration is a minimally invasive procedure that can be performed in a veterinarian's office with minimal discomfort to the dog.

The collected cells are then examined under a microscope to determine if they are cancerous or benign.

A biopsy, which involves surgically removing a portion of the lump, can also be used to diagnose cytology dog lumps.

Biopsy is a more invasive procedure than fine-needle aspiration but can provide more detailed information about the lump.

The veterinarian may also use imaging tests such as X-rays or ultrasound to help determine the size and location of the lump.

Imaging tests can help the veterinarian determine if the lump is likely to be cancerous or benign.

The veterinarian will typically take a complete medical history of the dog, including any previous health issues or symptoms, to help determine the best course of action.

Consider reading: What Does a Cancer Lump Feel like on a Dog

A complete medical history can help the veterinarian identify any underlying health issues that may be contributing to the lump.

In some cases, the veterinarian may recommend a wait-and-see approach, where the lump is monitored over time to see if it grows or changes.

A wait-and-see approach is often recommended for small, benign lumps that are not causing any symptoms.

Neoplasia and tumors are a common concern for dog owners, and understanding the basics can be reassuring.

Neoplastic populations are categorized based on cytomorphology, which includes round/discrete cells, epithelial cells, mesenchymal cells, and bare/naked nuclei.

Cells should be evaluated for cellular atypia, which is a general and nuclear criteria of malignancy.

Malignant cells cannot be distinguished from benign cells based on a single feature, and only when the majority of cells demonstrate numerous criteria should malignancy be suspected.

Biopsy and histopathologic evaluation should be considered if ambiguity or concurrent inflammation exists.

Criteria of malignancy can aid in predicting the biological behavior of a neoplasm, but morphology is not always indicative of biological behavior.

Benign tumors may not need to be removed immediately, and the location of the mass on your pet's body should be considered.

Most skin and subcutaneous tumors can be cured when diagnosed early, and most tumors are benign.

Fine needle aspirates can help identify many types of tumors, and they're quick and inexpensive.

It's worth knowing what you're facing, and staying vigilant about lumps on dogs is crucial, even if they've had multiple lipomas or other benign masses in the past.

The earlier we find tumors, the better, and with early diagnosis, less treatment will likely be required, and a smaller surgery may be curative.