Dog lumps and bumps – histiocytoma

What is a Histiocytoma?

These are usually angry looking, raised, hairless masses found on the skin of young dogs.
The most common areas are on the head, limbs and ears (often the front end of the body).
These are benign lesions and usually regress within a period of 3 months.

Informative image: Histiocytoma Skin lesion PottonVets

How to make a diagnosis:

Age of the dog
Cytology is a very useful tool in diagnosing histiocytoma, the appearance is relatively typical.  Cytology also helps to exclude other growths which can look similar.


What to do once a histiocytoma is diagnosed:

Once we are confident that a lump is a histiocytoma and it is not causing distress, we tend to monitor them regularly and allow them to regress spontaneously – this usually happens in 6 to 8 week period.
However these masses can be very irritating or be associated with infections/reactions, or regression may not progress as expected – in which case medication or removal and histopathology is indicated.

Informative image: Histiocytoma Microscopy PottonVetsCan’t we just leave all lumps to see if they disappear?

The simple answer is – this is a bad idea, and not in your pets best interests. There are many lumps that can look similar, some of these are very malignant, and the sooner they are removed the better. For example, mast cell tumours (MCT) are a very common and malignant tumour and can look exactly the same as a histiocytoma. We believe that using cytology helps us make choices that are in the best interest of your pets health at the early, and most important stage of evaluating tumours.

Dental radiography – revolutionising veterinary dentistry

Dental care is a discipline in veterinary medicine that was often not performed as well as we might have liked.

There are many reasons for this – a lack of practically useful technology and equipment is one of them.

Fortunately, as time goes by, more advanced veterinary equipment becomes available, which enhances our pet’s lives.  One piece of “new tech” equipment that has made a huge impact on pet’s quality of life is a dedicated veterinary digital dental radiography unit.

Digital dental radiography makes veterinary dental radiography possible because of the detail it provides and the speed advantage over old-fashioned film.  Pets need to be anaesthetized to perform dental procedures, so speed is very important.

It is not possible to see below the gum line without dental x-rays, however the use of a veterinary dental x-ray unit makes it possible to clearly identify the tooth roots and surrounding structures.

In this example, on evaluating the status of the bone surrounding the tooth, we can see that the bone in the angle between the middle tooth’s roots is destroyed. The full extent of the damage was not visible without the x-rays.


The best option in this case is to extract the tooth. 

This gives the dog immediate pain relief, removes of the source of infection, and it allows for the possibility of brushing effectively to keep the surrounding teeth healthy.


The tooth root sockets after extraction, showing that no tooth root fragments remain. 

Retained tooth root fragments can create future problems, this is why it is important to check that there are no remaining fragments – again dental radiography is the only practical way to do this.

Dog – lumpy tongue

Last year a very observant owner noticed a lump on his dogs tongue, and brought him to the surgery for examination.


There were no other abnormalities found on clinical examination.

From a patients point of view it is important and necessary to make an accurate diagnosis, check for other associated conditions, and remove the mass.

How did we approach this case: 

Firstly we performed cytology (we use a thin needle to take a small sample that we can examine under a microscope).  From this we could tell that this was not an infectious or inflammatory process, and that it was a true growth (tumour).

Once we knew we were dealing with a tumour, it became important to find out whether it was likely to be malignant (the bad tumours that either spread to other parts of the body, or recur when removed), or benign (no further problems once removed, or may spontaneously disappear).

We also knew that it was unnecessary to send bacterial cultures and antibiograms (grow bacteria and find out which antibiotics they are sensitive to) to a laboratory, as there was no indication of infection.

However we knew that it was important to check to see if there was any evidence of related underlying disease, and to check for potential spread of the mass.  Screening blood tests and chest x-rays were negative for related problems.

Once these routine procedures were completed we performed a wedge biopsy, in which we cut a small section or wedge from the mass.  This was then sent to an external laboratory where the mass is sliced into very thin sections and examined under a microscope by a veterinary pathologist.  The advantage of histopathology over cytology at this stage is that the structure of the mass is maintained, and a more detailed analysis of the mass can be made.

Cytology and histopathology are complementary procedures.

Now we waited for the histopathology report:IMG00805-20111101-1316

The histopathologist confirmed that this was calcinosis circuscripta.  With the information we had available, we knew the following important points:

  1. It was a benign mass
  2. There were no indications of it being associated with any other condition.
  3. It was likely to resolve completely with removal.

The final part:

We anaesthetised the patient and removed the mass.
This healed without complication and our patient is continuing to live in good health.

Happy dog, happy owners, happy result.


Informative image: tumour from dogs tongue calcinosis circuscriptaFor your interest:

Calcinosis circuscripta is a rare condition in  dogs (and other species), where a mass is formed by abnormal calcium deposits.  Complete removal is usually curative.







Rabbit vaccinations – Now a single annual injection

A new rabbit vaccine has been developed which offers protection against both of these fatal viral diseases.

Viral Haemorrhagic Diarrhoea (VHD) and Myxomatosis are both incorporated in a single vaccine – great news for bunnies!

Rabbits will benefit in 2 ways:

  1. The previous myxomatosis vaccine only lasted 6 months and needed to be injected twice a year to give full protection.
  2. The previous VHD vaccine could not be given at the same time as the Myxomatosis vaccine, so this was given separately from the Myxomatosis vaccine by at least 2 weeks.

From now on a single injection a year will replace these three.  A great improvement – I am sure every rabbit will agree!

Click here to register your rabbit.

Click here to book an appointment.

Cats – Itchy skin


Harvest mite from a cat’s underside this morning.

Autumn is upon us and with seasonal change comes a new set of parasite problems.

At the moment there is an external parasite called harvest mites that are just starting to cause a problem in our area.

Interesting points about harvest mites.

·      Can affect various animals including cats, dogs and sometimes humans.

·      Most cases occur between June and November (locally).

·      Most often attach between toes, on the underside of the belly and on ears.

·      Can cause intense itching.

·      Can sometimes be seen as red/orange specks.

·      Diagnosis is confirmed by microscopy.

·      Pets with access to fields are more likely to become affected.

So if you have an itchy dog or cat this autumn, one of the many potential causes is trombiculosis (harvest mite infestation).