By Dr. Gail Mason,
DVM, MA, DACVIM
Chief Medical Officer, Portland Veterinary Emergency & Specialty Care
While the majority of owned dogs are neutered, some owners choose to keep their male dogs sexually intact. The prostate gland produces nutrients to help sperm survive once inside the female’s reproductive tract. It is located on top of and surrounds the urethra (exit tube from the bladder). Because the prostate continues to enlarge in intact dogs (from testosterone influence), about 50 % of intact male dogs will experience age-related prostate issues starting as early as 4 years of age. These changes are expected, and not all of them lead to serious consequences. However, a “prostate exam” should be part of the physical exam in adult intact male canine. The veterinarian will perform a rectal exam to check the size and shape of the gland and note any signs of pain.
Symptoms of potential prostatic disease
The symptoms of prostatic health issues include bloody or blood-tinged urine dripping from the penis or found on bedding, increased frequency to urinate, straining to urinate, low sperm count, interrupted streams of urine or blood (“start and stop”), and even straining to defecate. Systemic signs of illness can also occur, which include lethargy, low appetite, back pain, stiff gait, and fever. These symptoms are also those expected with a lower urinary tract infection (“UTI”), so it is important to begin some diagnostic tests.
Types of prostatic disease:
• Benign prostatic hyperplasia (BPH): is the expected enlargement of the prostate gland over time. Most intact male dogs will eventually develop BPH, but not all will be symptomatic. The prostate can be palpably enlarged but should not be painful or be firm/irregular in shape.
• Prostatic abscesses: are walled-off areas of infection that can cause systems illness. These may need to be drained, followed by long-term antibiotic therapy. The prognosis is generally favorable with proper management. Castration can be considered to reduce the size of the prostate and risks of future infection. This can be done surgically or with certain medications.
• Prostatic cancer: it may surprise you that prostatic cancer is most frequently diagnosed in neutered males, as it is independent of testicular hormone influence. We do not know what the exact relationship is between neutered dogs and prostatic cancer. The cancer is uncommon, and may reflect that neutered dogs live longer, rather “cause and effect.” The two main types of prostatic cancer are urothelial transitional cell carcinoma (TCC), and primary prostatic adenocarcinoma (PCA).
Diagnostics used in prostatic disease
In mildly symptomatic dogs, routine diagnostics such as screening blood work (to assess overall health, kidney function, and evidence of infection), a physical examination (including a rectal exam), and a urinalysis are done. If an infection is deemed, a urine culture may be requested to formulate the antibiotic treatment plan. Because the prostate is enlarged and irregular, it takes longer for antibiotics to penetrate the gland and irradicate the bacteria. A screening abdominal radiograph (X-ray) can detect prostatic and/or lymph node enlargement, as well as calcification (more common with malignancy).
Advanced diagnostics
Abdominal ultrasound is a safe, noninvasive modality to evaluate the size, contour, and internal architecture of the prostate gland and surrounding structures. A needle biopsy can often be safely performed under ultrasound guidance and with mild sedation. This is a valuable technique in assessing the presence of prostatic cancer. In patients with known or suspected cancer, advanced imaging with a CAT scan can be considered.
What if my dog has prostate cancer?
As with most maladies, early discovery gives us the most options for extending a good quality of life. You can advocate for your pup by making sure he receives a thorough exam yearly. If he has recurrent “urinary tract infections,” the degree of suspicion for potential abscess or malignancy should spark an investigation.
Are there any treatments for prostatic cancer?
Prostatic cancer is not yet curable in dogs as it may be in humans. However, many times it can be successfully managed for lengthy periods of time. Surgery, which is not uncommon in humans, is not typically utilized in dogs due to a high complication rate. Options include chemotherapy (which is well-tolerated in dogs) to reduce the size of the tumor and delay its progression. Newer, oral “targeted drugs” (as used in human medicine) are becoming more available in veterinary medicine and can offer significant benefits. Newer techniques such as “stereotactic radiation treatment “(SRT) can deliver radiation to very precise targets minimizing damage to adjacent tissues and avoiding systemic radiation effects. The future is bright!