Gingival hyperplasia
Overgrowth of the gum tissue itself, sometimes around many teeth. It is not a tumour, but plaque collects between the enlarged gums and the teeth.
Service
Oral masses in dogs and cats: biopsy and removal
Any mass in a dog’s or cat’s mouth should be checked by a vet, even if it is small and not painful. A benign epulis and a malignant tumour such as melanoma or squamous cell carcinoma can look very similar, so the diagnosis is made by biopsy with histopathology. The extent of surgery depends on that result and on how far the mass involves the bone.
I examine the mouth, assess the bone with dental radiography, take a biopsy and remove the mass together with the involved tissue when clinically indicated; everything removed is sent for histopathology. If the mass is malignant or needs more extensive surgery, further tests and a consultation with a veterinary oncologist may be needed.
Why every mass in the mouth needs checking
A growth in the mouth is a description, not a diagnosis. Gum overgrowth, a benign epulis and a malignant tumour can share the same colour, size and firmness. Melanoma is not always dark — it can be pink, without pigment.
The fact that your pet eats and shows no pain is not reassuring either: in the early stages oral tumours may cause few signs. At the same time, a small mass is easier to remove with an adequate margin than a large one.
What you can see by eye or in a photo
- Colour and size of the mass
- Whether it bleeds
- Whether the surface is ulcerated
- Whether nearby teeth are loose
What only an examination can show
- The tissue type — benign or malignant
- How deeply the mass has invaded the bone
- Whether lymph nodes or lungs are affected
- What margin is needed for removal
That is why I base the treatment plan on the examination, radiographs and histopathology, not on a photograph.
What a growth in the mouth may turn out to be
Below are common possibilities. This list cannot be used to make a diagnosis at home: the type of mass is confirmed by histopathology.
Peripheral odontogenic fibroma
A typical benign epulis in dogs: a firm mass next to a tooth. To stop it coming back, it is removed together with the tissue it grows from.
Acanthomatous ameloblastoma
A benign tumour in dogs that does not spread to other organs but invades the jaw bone. It is removed with a margin, often together with part of the bone.
Melanoma
A malignant tumour that can be dark or pink. It may grow quickly and spread to lymph nodes and lungs.
Squamous cell carcinoma
The most common malignant oral tumour in cats; it also occurs in dogs. It can look like a non-healing sore, jaw swelling or loose teeth.
Fibrosarcoma and other tumours
A firm mass that may look harmless but invades the surrounding tissue deeply.
Why “waiting and watching” or cauterising at home is risky
A malignant tumour does not pause while we watch: the larger it grows, the more extensive the surgery and the harder it is to remove completely. That is why I recommend not delaying an examination for any new growth.
- ✓Do not cut, tie off with thread or cauterise a growth: it causes bleeding, burns, infection and pain
- ✓Incomplete removal leaves cells of the mass in the tissue and can complicate later surgery
- ✓Damaged tissue is less suitable for histopathology, making the diagnosis less accurate
- ✓Ointments, gels, antibiotics or home remedies do not treat oral masses; if the surrounding inflammation settles for a while, it can give a false impression that the problem is going away
When to show a mass to a veterinary dentist
- ✓A lump, bump or thickening on the gums, palate, tongue, lip or cheek — even a small one that does not seem to bother your pet
- ✓The mass is growing, bleeding or ulcerated on the surface
- ✓Teeth next to the mass are loose, have shifted or have fallen out
- ✓Swelling or asymmetry of the jaw or face without an obvious injury
- ✓Blood in the saliva, bad breath, careful eating or dropping food
- ✓In a cat, a sore or thickening in the mouth that does not heal
- ✓A mass that was removed before has come back
- ✓You need a biopsy or a second opinion on the treatment plan
Symptoms that may indicate this procedure
Growth or lump on the gums
Only a biopsy, not a photo, shows what a gum growth is.
More about gum growths →Blood from the mouth or in saliva
Blood from the mouth needs a vet’s assessment.
About blood from the mouth or in saliva →Facial or under-eye swelling
Often linked to a tooth — needs a prompt exam.
What to do about facial swelling →Loose or lost tooth
In an adult pet, a loose tooth needs an exam.
What loose or lost teeth mean →How diagnosis works
- ✓Consultation: size, firmness and location of the mass, the condition of nearby teeth and the lymph nodes under the jaw
- ✓Examination under anaesthesia and dental radiography: whether the bone and tooth roots are involved
- ✓Biopsy with histopathology — the basis of the treatment plan; cytology alone may not be enough
- ✓CT may be needed to assess the extent of bone involvement more precisely and plan surgery
- ✓If a malignant tumour is suspected, lymph node assessment and imaging of the lungs may be needed
- ✓Pre-anaesthetic assessment of anaesthetic risk
How biopsy and removal work
- ✓Biopsy: sampling part of the mass, or removing the whole mass for examination — depending on its size, location and likely type
- ✓Removal of a benign mass together with the tissue it grows from — with the tooth when clinically indicated
- ✓Removal with a margin of healthy tissue when the type of mass requires it
- ✓Bone work when clinically indicated, including piezosurgery
- ✓Bleeding control and wound closure
- ✓Histopathology of all removed tissue, including assessment of the margins
The extent of surgery is determined not by the size of the visible part but by the type of mass and the depth of involvement. That is why some patients have a biopsy first, and definitive removal is planned after histopathology.
Biopsy: part of the mass or all of it at once?
There are two approaches. In an incisional biopsy, part of the mass is taken for analysis and definitive surgery is planned after histopathology. In an excisional biopsy, the whole mass is removed and examined — this suits small masses that are most likely benign.
The choice depends on the size, location and likely type of the mass. If a malignant tumour is suspected, the first operation must not compromise the second: unplanned incomplete removal can mean that more tissue has to be removed later.
Cytology alone — examining cells from a smear or fine-needle sample — may not be enough: oral masses are often inflamed, so the sample may contain mostly inflammatory cells. I explain the difference between cytology and histopathology in more detail in the article “Diagnosing a growth on the gums in a dog or cat”.
Incisional biopsy
- Part of the mass is sampled
- Diagnosis before major surgery
- Allows the margin and extent to be planned
- Suits suspected malignant tumours or large masses
Excisional biopsy
- The whole mass is removed
- Diagnosis and treatment in one procedure
- Suits small, probably benign masses
- Histopathology also assesses the margins
Sometimes biopsy and removal are combined, sometimes separated. I decide this individually after examination and radiographs.
Why margins matter for malignant tumours
A malignant tumour usually extends beyond the visible part: its cells invade the gums, bone and surrounding tissue. So removing only the “lump” is not enough — a margin of healthy tissue is needed, which for many malignant tumours includes part of the jaw bone together with teeth.
After surgery, the pathologist examines the edges of the removed tissue for tumour cells. If the margins are clean, the chance of long-term control is better; if not, repeat surgery or other treatments prescribed by a veterinary oncologist may be needed.
Why anaesthesia is needed
Examining the mass, dental radiographs, biopsy and removal are performed under inhalational anaesthesia with local dental blocks; the anaesthetic is given and monitored by a separate veterinary anaesthetist. A biopsy is usually combined with a full dental examination to gain as much information as possible from one anaesthetic.
More on this: anaesthesia in veterinary dentistry.
When more extensive surgery or referral is needed
Some masses can be removed as part of a dental procedure: benign epulides, gingival hyperplasia and small masses without bone involvement. If histopathology confirms a malignant tumour or radiographs show deep bone involvement, complete removal may require partial removal of the lower or upper jaw.
In these cases I explain which further tests are needed and discuss treatment options with you, including a consultation with a veterinary oncologist or surgeon. The aim is for the first operation to be properly planned rather than rushed.
- ✓A malignant tumour on histopathology
- ✓Bone involvement on radiographs or CT
- ✓Enlarged or abnormal lymph nodes
- ✓A large mass or a location that makes removal with an adequate margin difficult
- ✓Recurrence after previous removal
Histopathology: what examining the removed tissue shows
Every piece of tissue I remove from the mouth is sent for histopathology. Without it there is no way to know whether the mass was benign, whether it was removed completely and whether further treatment is needed.
The result does not arrive on the day of surgery. When it is ready, I explain it to you in plain language, and together we decide on the next steps: follow-up checks, further surgery or an oncology consultation.
Recovery and follow-up checks
After a biopsy or removal of a small mass, the animal usually returns to eating within the first few days. After more extensive surgery, recovery takes longer, and some patients may need a temporary feeding tube.
A follow-up check is needed to assess wound healing. After that, regular oral examinations help spot recurrence or a new mass early; I set their frequency according to the diagnosis. At home, lift your pet’s lips from time to time and look at the surgical site and gums.
- ✓Pain relief according to an individual plan
- ✓Soft food during healing
- ✓No chews, sticks or hard treats until the wound has healed
- ✓Contact me before the planned check if you notice bleeding, swelling, bad breath or your pet stops eating
Technology and equipment
Dental radiographyPiezosurgery when clinically indicatedHistopathologyInhalational anaesthesia with monitoring
Possible results
- ✓A diagnosis confirmed by histopathology rather than a guess from a photo
- ✓Removal of the mass appropriate to its type and extent
- ✓A clear plan for further treatment and monitoring
- ✓Less bleeding, pain and discomfort when eating, if the mass was causing them
Recovery and follow-up checks
- ✓An individual pain-relief plan and written instructions
- ✓Soft food during healing; no chews or hard treats
- ✓An explanation of the histopathology result and the next steps
- ✓A check of wound healing
- ✓Regular oral examinations to spot any recurrence early
- ✓A consultation with a veterinary oncologist if the diagnosis calls for it
What affects the fee
The fee depends on the diagnosis and the extent of treatment: the size and location of the mass, bone involvement, whether teeth need to be removed, the extent of surgery and any further tests. It is calculated after examination and dental radiography, and I explain the plan, including biopsy and histopathology, before treatment begins.
Frequently asked questions
Not necessarily. Some gum masses are benign, such as gingival hyperplasia or an epulis. But melanoma, squamous cell carcinoma or fibrosarcoma can look almost the same, so a malignant tumour cannot be ruled out by appearance. A biopsy with histopathology gives the answer.
Consultation“Epulis” is a general name for a mass on the gum. Different processes can sit behind it: a peripheral odontogenic fibroma is benign and does not spread but may return after incomplete removal; an acanthomatous ameloblastoma also does not spread to other organs, yet it invades bone. Sometimes an “epulis” turns out to be a malignant tumour. Only histopathology determines the type.
I do not recommend it. If the mass is malignant, incomplete removal leaves its cells in the tissue and complicates the next operation. So the nature of the mass and the extent of involvement on radiographs are established first, and only then the extent of surgery. Every removed piece is always sent for histopathology.
An oral biopsy is taken under general anaesthesia with local dental blocks: your pet is asleep during the procedure, and the local blocks and pain relief afterwards control pain. I usually take dental radiographs under the same anaesthetic to assess the bone. How long the biopsy wound takes to heal depends on its size.
Anaesthesia and safetyPart of the mass may be hidden in the bone. Dental radiographs show whether bone and tooth roots are involved and help plan the margins of removal. They can underestimate the depth of involvement, so CT may be needed to plan more extensive surgery.
Dental radiographyOral masses in cats need particular attention: squamous cell carcinoma is the most common malignant oral tumour in cats and can look like a non-healing sore, jaw swelling or loose teeth. Benign processes such as granulomas also occur. A biopsy helps tell them apart, so it is best not to delay the examination.
It can, depending on its type and on whether it was removed with an adequate margin. That is why removed tissue is examined with margin assessment, and regular follow-up checks are needed after surgery. The earlier a recurrence is spotted, the more treatment options there are.
Oral surgeryRelated services
Oral Surgery
Complex dental procedures: extractions, soft-tissue work and piezosurgery where indicated.
More about oral surgery →Dental Radiography
Full-mouth X-rays reveal roots, bone and changes hidden beneath the gumline.
How dental radiography works →Piezosurgery
Piezosurgery is a modern way to work with bone using controlled ultrasonic micro-oscillations. It enables more precise complex dental procedures, helps protect adjacent soft tissue and minimises unnecessary tissue trauma.
More about piezosurgery →Anaesthesia in Veterinary Dentistry
Inhalational anaesthesia with monitoring provides controlled conditions for comprehensive dental diagnostics and treatment.
Anaesthesia safety →© dr.vetstomat. Original content.
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