Mast Cell Tumors - the great pretenders...

A small lump had appeared on Poppy the Boxer’s chest. Thankfully her owners brought her straight in for a check up.

A sample of cells was taken using a needle (a fine needle aspirate). This sample was placed on a slide, had special stains applied and was examined under a microscope. A large number of mast cells were present.

Mast cells normally respond to inflammation and allergies. Sometimes there are a cancerous proliferation of these cells and the formation of a tumour. Some of these tumours can be very aggressive and spread elsewhere in the body.



Mast cell tumours are commonly referred to as 'the great pretenders' because their appearance can be varied. The only way to diagnose them accurately is to take a small biopsy under a general anaesthetic and have this assessed by a pathologist.

Poppy’s biopsy indicated that the lump was a low grade mast cell tumour and it was removed with a second surgery. The excised lump was then sent to the pathologist to ensure it had been removed completely. Poppy got the all clear but will need to be monitored closely in the future for more tumours.

If you notice a new lump on your pet you should arrange an appointment with us. All lumps should be checked by fine needle aspiration to rule out the presence of any concerning cells.