By Dr Steve Surujbally
Angiomas
This is a simple tumour formed by a mass of small blood vessels (or in spaces where blood or lymph circulates). We know these angiomas in humans as the common ‘birth mark’. In dogs, this condition is often seen under the jaw, causing a fluctuating swelling which may rupture thus creating a continuous seepage of a clean watery fluid (lymph).
Haematoma
I suppose I should mention, under the heading of ‘skin tumours’ (swellings in, above and under the skin), the haematoma which is an amassment of blood forming a definite swelling. Anything that caused the rupture of superficial blood vessels, thud leading to a bleeding (with nowhere for the blood to go), will result in an accumulation of blood in that area. On some occasions, for example, if the dog has ear mites or a foreign object (e.g. a grass seed) lodged in its ear, the dog will shake its head vigorously. The centrifugal force created by the flapping ear (especially if the ear hits the wall) is enough to rupture tiny blood vessels. The ear flap then swells up. This condition is known as an ear haematoma. We will deal with this malady, in more detail at some other time.
Generally speaking, small haematomas are not a problem and the swelling will subside. Large haematomas have to be cut open and drained. The ear haematoma needs surgery.
Skin cancer
Many cancers in dogs occur on or in the skin. These cancers exhibit themselves as growths or ulcers (sores). However, one must be careful not to confuse a simple skin ulcer (caused, for example, by persistent scratching and subsequent bacterial invasion of the damaged site) with a cancer. A skin cancer would usually exhibit itself in the form of an ulceration of the skin accompanied by bleeding and the inability of the persisting sore to heal. Lumps and bumps on skin (for example the skin tumours which we discussed last week [March 23]) are not always cancerous.
Let’s look at some skin tumours that are, or have the potential to become cancers.
(1) Sebaceous adenomas
Big words to tell you that the cancer is originating from the oil producing (sebum in Latin means grease) glands of the skin. Actually, these are quite common, especially in older dogs. The growth has a cauliflower-like appearance, which is associated with an ulceration of the skin in the affected area. Any cancer of this nature should be surgically removed, especially if the size is larger than 2½cm (approximately one inch).
(2) Mast cell cancers
Middle-aged dogs (around six to eight years old) tend to be afflicted with this problem that arises in certain cells of connective tissues. These cancerous growths occur on the foreskin of the penis, on the neck, lower abdomen and hind legs. These growths tend to cluster and converge into one mass that is less than an inch in diameter. The great problem of this type of skin cancer is that malignant cells disassociate themselves from the cluster and redeposit themselves elsewhere (metastasis) in the animal’s body where a new cancer develops. For this reason, I always advise that such growths be surgically removed early in their development.
Of course, one could always take a sample (biopsy) of the growth and have it histologically examined in the laboratory. In this way, we’ll know if it is malignant.
But, as I have said before, many tumours (swelling) have the potential to become malignant cancers even when they began as simple swellings.
(3) Melanoma
In dogs, melanoma are often malignant tumours. The word ‘melanoma’ is related to the word ‘melanin’, which is a black pigment in the skin. The term, our often has its origin as a mole on the skin. When this mole begins to get bigger and to develop into a bump, one should take it seriously (especially if it starts to bleed). Any mole that becomes elevated on the skin should be surgically excised.
(4) Histiocytomas
These tumours, for whatever reason, seem to develop primarily in young dogs. They grow rapidly, usually on the feet and face (ears). More than most cancers these histiocytomas are very painful to the touch. One recognizes them because of their raised, button-like, inflamed appearance.
This is a complicated growth (from a scientific point of view) because often they regress on their own and just cease to exist. I take a wait-and-see approach to these tumours. After all, anytime they get out of hand, I can always intervene surgically. There are other types of skin cancers described in the literature, but are of a lesser importance because the incidence is small. Thus, for our discussions here, we’ll not deal with them.
Please implement disease preventative measures (vaccinations, routine dewormings, monthlyanti-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 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.
