Oncology Index

These are uncommon skin tumors in dogs, but occur mainly in middle aged to older animals with an average age of occurrence of 10 years. The tumors can be difficult to diagnose and have been given several different names so the precise incidence is uncertain.

The prostate gland stores sperm after they have been made in the testicles and produces fluid that contains essential nutrients for the sperm. Cancers of the prostate are rare but usually involve the cells that make the fluid. Although true cancer is rare, non-cancerous overgrowth (hyperplasia) of the gland is common. Both the non-cancerous and cancerous growths have similar clinical signs. There is usually pain in the area and pressure on the back passage (rectum) interfering with passing faeces. Occasionally there is infection or interference with passing urine.

This tumor is a disordered and purposeless overgrowth of sebaceous gland cells. These glands are attached to the hair follicles where their function is to lubricate the hairs and skin. Almost all sebaceous gland tumors are benign and can be permanently cured by total surgical removal. Many are multiple. Malignant tumors, which have the potential to spread to other parts of the body, are extremely rare.

Lymphocytes are key cells in the body’s ability to fight and prevent infection (’immunity’). Lymphocytes are found in tissues throughout the body, in the blood and in particular concentration in lymph nodes (’lymph glands’) and other ’lymphoid tissue’. Lymphocytes are of two main types, called ’T’ lymphocytes and ’B’ lymphocytes. Each plays a different role in immunity.

This is a tumor originating from the connective tissue of, or beneath, the skin. The tumor is diverse in appearance and several different cell lines produce tumors of similar appearance. Some pathologists try to classify this group of tumors by their origin cells but this is not always possible. There are therefore several names that can be used for the tumors of this group including fibrosarcoma, Schwannoma, peripheral nerve sheath tumor, neurofibroma and haemangiopericytoma. Most are slow-growing and few have fibrocyte markers. The tumors often recur locally after surgical removal but spread to other parts of the body (metastasis) is rare.

This is a malignant tumor of skin epidermal cells with varying degrees of differentiation. Tumors of this type occur in people and all domestic species. The tumor is related to basal cell tumors. Most can be cured surgically, the exception being those arising in the nail beds. 

Tumors of the epithelial, glandular stomach lining include non-cancerous polyps and some types of chronic (hyperplastic) gastritis. Malignant epithelial tumors (gastric adenocarcinomas) cause progressive illness. This usually starts only a few weeks before diagnosis but within that time, they have usually spread locally and to distant organs. Many recur following surgery. 

The testicle (testis) contains several different cell types. These include the germ cells, which make sperm, the supporting and nourishing Sertoli cells, and the hormone-producing interstitial (or Leydig) cells.

Any one or more than one of these cell types may become cancerous. The germ cells that make sperm may become cancers known as seminomas, the Sertoli cells become Sertoli cell tumors and the interstitial cells become Leydig or interstitial cell tumors. Most of the tumors are benign. The tumors are usually permanently cured by castration. This needs to be total (i.e. both testicles) as many tumors occur simultaneously in both testicles. Spread to other parts of the body (metastasis) is unusual if the cancer is surgically removed at an early stage.

This is a common tumor, only found in dogs. It has a patchy world-wide distribution including parts of the Caribbean, USA, Southern Europe, Asia and Africa. It is transmitted by physical transplantation. It occurs in both sexes and may appear as multiple subcutaneous nodules on the genitalia, lips and other parts of the body.

Two months ago, at a party hosted by Manhattan’s swanky Spike Gallery, I helped unveil a life-size bronze bust of my dog Sam by the talented sculptor Jennifer Weinik. I was feeling celebratory: After a bout with cancer, Sam had been in remission for almost a year.

In his prize-fight against cancer, my dog Sam is looking like a champ to me.

Sometimes, several people have to travel many miles to help one dog beat a dangerous disease.

My dog Sam’s report has returned from the lab: Six of his tumors were benign, but the seventh was a malignant plasmacytoma. The strategy of the doctors at the Center for Specialized Veterinary Care in Westbury, N.Y., is to remove any and all lumps before they have a chance to mutate into something fatal that could spread to Sam’s vital organs.

I waited a while before trying Neoplasene on my dog Sam. This powerful medicine made of alkaloids from the bloodroot plant is touted as an exciting new hope in the fight against cancer, but it’s also somewhat controversial: some veterinarians flat-out refuse to even consider it.

By now, you’d think my dog Sam would be getting suspicious. For the past two weeks, it’s been raining extra-special treats: hot dogs, pizza, falafel, liverwurst, cheddar cheese, burgers (both the meat and meatless variety).

Of all the compelling reasons to quit smoking, this one should make dog lovers sit up and take notice: there’s ample scientific evidence to suggest secondhand smoke can cause cancer in companion animals.