Continued from last week
Well, we are coming close to the end of this thematic – tumours and cancers. After today, we will treat with tumours of fatty tissues in the skin (lipomas) and then finally discuss melanomas, a skin condition similar, yet a bit different, to that which can afflict humans. Finally, we’ll do a wrap-up of the theme which I hope – after such lengthy discussion – is less traumatic to the pet owner suddenly seeing swellings, lumps, etc, on his/her animal’s skin.
Papillomas are caused by small viruses. The jury seems to be still out as to whether other agents can be associated with the development of warts. Some mammals have several distinct papilloma viruses. Humans, for example, have more than 20; dogs have three (discovered so far), and rabbits have 2 (usually attacking the ears). The virus is transmitted by direct contact with an infected animal, or – as the literature on the subject is proposing – via insects. Papillomas have been reported in all domestic animals, in birds and in fish. Multiple papillomas of the skin or on the oral surfaces (inside the mouth) are to be found mostly in young dogs. Single papillomas (warts) are more frequent in older animals.
In dogs, there seem to be three distinct types of papilloma infection. Firstly, the multiple growths (surely caused by viruses) exhibit themselves on the lips and the inner surface of the mouth and tongue, leading right up to the oesophagus (the gullet – that tube which conveys solid food and liquids to the stomach). Sometimes the warts grow on the corners of the eyes and adjacent haired skin, and even on the thin membrane which covers the front of the eye. Of course, when the oral cavity is severely affected the poor animal cannot munch and gnaw well, or even swallow.
The second presentation is called cutaneous (skin) papillomas (warts). These are also caused by viruses and are indistinguishable from the warts that develop in the mouth and lips. These papillomas tend to be singular and develop in older dogs, especially Cocker Spaniels (even though I have seen these papillomas on many different breeds). These papillomas may be confused with solitary hanging skin growths in elderly dogs. These latter can be easily excised (under anaesthesia – local or general) or simply tied off.
I should mention in passing, that the scientific literature has described a similar papilloma condition on the footpads of dogs. We have seen such elevation of the hard skin of the footpads, and we simply pare (trim) them off until a bit of blood oozes and treat as if it were a minor open wound (cleaning, antibiotic ointments, bandage, etc).
Thirdly, there is a papilloma exhibition called fancily cutaneous (skin) inverted papilloma which seems to afflict mostly young mature dogs. The lesions develop on the skin of the abdomen (at the bottom) and appear as raised nodules with a hard centre.
Cats tend to develop papillomas too, but if they appear it would be inside the mouth. In cats, I don’t hesitate to advise that the papillomas must be excised as soon as possible.
The bad news in all this is the fact that papillomas in dogs can progress to be invasive carcinomas (malignant tumours = cancers).
The good news is that infectious papillomatosis is a self-limiting disease, although the duration of warts varies considerably. A variety of treatments have been advocated without agreement on efficacy. Surgical removal is recommended if the warts are sufficiently objectionable.
However, because surgery in the early growing stage of warts may lead to recurrence and stimulation of growth, the warts should be removed when near their maximum size or when regressing. Affected animals may be isolated from susceptible ones; (because of the long incubation period), many are likely to have been exposed before the problem is recognized.
Enjoy the week!
Please implement disease preventative measures (vaccinations, routine dewormings, monthly anti-heartworm medication, etc) and adopt-a-pet from the GSPCA’s Animal Clinic and Shelter at Robb Street and Orange Walk, if you have the wherewithal to care well for the animals. Do not stray your unwanted pets, take them to the GSPCA’s Clinic and Shelter instead. If you do not wish your pet to have puppies or kittens, you may exploit the GSPCA’s free spay and neutering programme. If you see anyone being cruel to an animal, or if you need any technical information, please get in touch with the Clinic and Shelter by calling 226-4237.