When the articles on cancers and tumours commenced in May, we had no inkling that so many weeks/ months would be needed to cover the salient topics associated with this ailment. And it seems that we will never stop. Last week, I had mentioned that we would decide on the new topic. Well, as our readers demand, there are a few more issues which should be considered before we conclude the discussions.
For starters, a reader of this column called in to ask whether a swelling of a dog’s extremities can be considered a tumour, since I have been writing that the word ‘tumour’ really means ‘swelling.’ Well, if the swelling is localized in one area of the leg (eg a swelling on the elbow like in the case of the hygroma/bursitis complex discussed in the column of June 1), then, yes, it can be considered a tumour (not necessarily a cancer). If the entire leg is swollen, then that’s a whole different matter, with possible serious origins (not lastly a heart condition). You would need to see your veterinarian immediately.
Then, a note was received, from a colleague no less, reminding me that there are ailments on the skin that could exhibit themselves as swellings, but which the column had not touched. This was true, but I had decided to treat with the ailments he mentioned at a later date, when the discussion would centre on dermatitis and dermatoses cases.
My colleague firstly mentioned ‘collie nose’ which is a relatively rare disease, but with which vets are confronted, not lastly in white haired dogs (mostly, but not only). This condition is known scientifically as a ‘nasal solar dermatitis,’ which affects the bridge of the nose and is probably precipitated by solar radiation.
Once the skin in this nasal area becomes vulnerable, secondary bacterial invasion is quite possible. The vet then has to treat not only the inflammatory nature of the condition but also the ulceration that follows.
As an aside, please try to differentiate (with the help of your vet) this swelling on the nose-bridge from an insect (bee) sting or a bite from another dog.
And, if that were not enough, he referred to a blackened swelling in the area of the dog’s armpit and in the area located between the inside of the hind legs (groin area).
Again, my colleague was right; however, the column is currently dealing with tumours and cancers. The clinical reaction pattern of the condition my colleague mentioned actually has a name: Acanthosis nigricans (AN); the ‘ancanthosis’ refers to the thickened roughness of the skin and the ‘nigricans’ has to do with the darkened colouration.
Interestingly, since it has been mentioned, I do come across such patients with this abnormalcy on enough occasions to warrant mention in this column. Note I did not say ‘disease’ or ‘ailment,’ since the dogs (usually Dachshunds or those with some Dachshund genes) don’t seem to be suffering. I think that really it is the owner who finds the condition not aesthetically pleasing. I have never seen AN in cats.
The cause is not clearly understood, but clinical signs are invariably a result of inflammation, in the groin and arm pit area, due to constant friction in those areas resulting sometimes in a dermatitis and even an open wound.
I should mention that the smart books have found that a secondary AN can be associated with obesity, hormonal imbalances, food allergies and even common skin infections.
Actually, since there is no definite cure, I have seen this condition spread to the entire neck area, and the entire groin region, around the eyes, and even to the extremities (front and hind legs). As the problem continues, it evolves into real ailments, like hair loss (alopecia) and sebaceous gland adenomas (see July 6).
If one observes the problem at the onset, early cases may respond to special shampoo therapy and topical anti-inflamatories. If the lesions progress, more aggressive therapy may be useful. Your vet will have to advise you on the chemical intervention and the dosage rates.
I think we have covered the most salient topics associated with cancers and tumours.
Next week we will conclude this series with a discussion on euthanasia as it relates to cancers and inoperable tumours.