Prostate Cancer In Dogs

Prostatic tumors are rare, locally aggressive neoplasm that develops from the tissues of the prostate gland. Prostatic cancer is rare in dogs affecting both castrated (neutered) and non-castrated dogs.

The prostate is a semioval, bilocular, male accessory sex gland located below the rectum and behind the bladder, and it secretes seminal plasma components. When a tumor develops in the prostate, it presses on surrounding organs (such as the urethra) and manifests a variety of symptoms. The median age of diagnosis is 10 years old. Prostatic cancer is relatively rare in dogs and has a low prevalence of less than 2%.

Canine prostatic adenocarcinoma is the most common type of prostate cancer in dogs and it accounts for more than 80 percent of prostate cancer diagnoses. Neutered dogs may present a greater chance of developing prostatic adenocarcinoma, almost 3 times greater than non-neutered dogs. Other rare types of malignant cancers that affect the prostate are fibrosarcoma, Carcinoma, squamous cell carcinoma, and leiomyosarcoma.

Benign (e.g. leiomyoma) prostatic hyperplasia can also develop and are similar to benign prostatic hyperplasia (BPH) in older men, in the same way, it affects older dogs of more than 9 years. Transitional cell carcinoma (ductal and urothelium instead of acinar epithelium neoplasia) is more prevalent in neutered male dogs

Cancer of the prostate metastasizes and spreads to other areas and organs of the body, including the lymph nodes, lungs, and bones.

General symptoms of prostate cancer are

• Stranguria/dysuria (Difficulty urinating)
• Hematuria (Blood in the urine)
• Frequent attempts to urinate
• Abnormal posture (especially while urinating)
• Constipation, obstipation, dyschezia, tenesmus
• Lameness in the hind legs
• Abnormal gait with short steps
• Pain/General weakness
• Fever
• Weight loss

• For dogs with small tumors (diameter less than 3cm): primary tumors and if the tumor hasn’t spread, the most appropriate therapy is local surgical excision. Post-operatively to improve the tumor control, radiotherapy may be used.
• In dogs with primary tumors (greater than 3cm), no evidence of metastasis: chemotherapy drugs can be used to attempt to shrink the tumor.
• IM/IGRTradiation therapy: This is a relatively new technique (image-guided and intensity-modulated radiation therapy).
• Again, palliative radiotherapy for urinary obstruction can be used as short-term relief.
• Some dogs have tumors that have spread only to the regional lymph nodes but no further. Surgical removal of enlarged lymph nodes (sublumbar lymphadenopathy).
• When there is any significant obstruction of the urethra, a surgical stent is placed to keep open the urethra for urination.

The best way to manage prostate cancer is to keep an eye on your dog closely, especially for aged dogs. Detection of prostate disease in the pre-malignant stages can help give your dog the highest chance of survival.

When dogs are diagnosed with inherited types of prostate cancer, it is important to take measures to avoid breeding or neutering the dogs (if they does survive to adulthood) to remove affected dogs from the gene pool.

Large Dog Breeds, Male Dogs, Senior Dogs, Airedale Terrier, Beagle, Bouvier Des Flandres, Doberman Pinscher, German Shorthaired Pointer, Miniature Poodle, Norwegian Elkhound, Shetland Sheepdog, Scottish Terrier

1. Causes:

• Inheritance
• Old age - male dogs over eight years old.
• Higher in uncastrated dogs
• Exposure to chemicals, such as the pesticides and herbicides, nitrosamines, cyclophosphamide

2. Types:

Primary prostate cancer: Cancer that originates in the prostate gland itself is called primary prostate cancer. Most primary prostate cancers are destructive and with high metastatic potential. For example, canine prostatic adenocarcinoma.

Secondary prostate cancer: Cancer that spreads from another organ or metastasized to the prostate.

3. Morbidity:

Benign Prostatic Hyperplasia (BPH)

• The long-term effect of testosterone causes prostate enlargement; also called benign prostatic hypertrophy, this is a premalignant condition, especially in neutered dogs.

Adenocarcinoma

• A carcinoma arising from the glandular tissue in the prostate; This most malignant type of prostate cancer tends to be locally invasive in the surrounding tissues and has a high rate of metastasis

Transitional cell carcinoma (TCC)

• A carcinoma arising from the transitional epithelium cells in the prostate; this is the less malignant type and as slower growing than adenocarcinoma. TCC is also the most common type of bladder cancer.

4. Mortality:

Mortality rate of benign types of prostate cancer is almost zero. Adenocarcinoma of the prostate is highly aggressive and it should be diagnosed early as well as treated promptly. If it is not discovered in the early stages, then the mortality rate will be higher

5. Diagnosis:

• Complete blood count, chemistry panel
• Urinalysis
• Contrast X-rays
• Ultrasound scans
• Biopsies

6. Prognosis:

Prognosis can differ based on the time of diagnosis and aggressiveness of the tumor. When the cancer is detected early, before any metastasis, radiation and chemotherapy treatment may be effective. When there is the presence of significant metastasis, vets may recommend against conventional treatment and will treat your dog’s clinical signs to make them comfortable.

Contact your vet right away, if you notice any of the following:

1. Prostate enlargement
2. Stranguria/dysuria (Difficulty urinating )
3. Hematuria (Blood in the urine)

What a cancer prevention diet for a pet looks like

In general, the breakdown looks like this:

• High Protein, Good Fats and Low Carbs, antioxidants and cancer-fighting nutrients.
• Dogs: 50% veggies (dark leafy greens, carrots, broccoli, green beans, etc are good choices) + 50% protein (chicken or beef is best).
• Fresh, lean protein (Lean ground beef, White-meat skinless chicken or turkey).
• Vitamin-rich fruits and veggies: legumes, such as lentils, peas or beans, cauliflower cabbage, broccoli, tomatoes, and citruses, such as oranges and limes.

If prostate cancer is detected early, before any metastasis has happened, then survival time can be extended with more definitive treatment. If cancer has metastasized to distant regions, management of the disease symptomatically is often performed for as long as possible.

The chances of recovery for prostatic adenocarcinoma are poor. Once the quality of life has declined or clinical signs cannot be controlled, Euthanasia may be required.