Parathyroid tumors are usually benign

These tumor produce a hormone that elevates the calcium level in the blood

Treatment usually is curative, resulting a normal life span for your companion

What are Parathyroid Tumors?

• Dogs have four parathyroid glands located within the neck. These glands control the level of calcium in the blood stream. Many body systems such as the heart, nervous system (brain, nerves and spinal cord), intestinal tract, muscles and many other systems function properly only with a normal blood calcium level in the blood.
• These tumors are uncommon in dogs and even less common in cats.
• They are usually benign, with rare spread of the tumor to other parts of the body.
• The primary problem with with tumor is that it is functional, producing excessive amounts of a hormone called parathyroid hormone. This hormone results in excessive amounts of calcium in the blood stream
• About 10% of patients have multiple parathyroid tumors

Signs

• Breeds most commonly affected
  • Keeshonds
  • Labrador retrievers
  • German shepherds
• Signs result from high calcium levels in the blood include:
  • increased thirst and urination
  • lethargy
  • weakness
  • poor appetite
• Signs associated with the urinary system are caused by crystals or stones that form in the urinary tract and include:
  • straining to urinate
  • passage of blood-tinged urine
  • inability to pass any urine caused by a stone lodged in the penis (typically a male problem)

Diagnosis

• Initial tests that are typically done include a complete blood count, biochemistry profile and urinalysis
• In patients that have an elevated calcium level, a test is performed to measure the amount of parathyroid hormone
• Chest x-rays may be recommended to rule out spread of the cancer to the lungs
• X-ray or ultrasound of the urinary tract is used to rule out the presence of calcium oxalate stones in the urinary tract (bladder, kidneys, ureters, and urethra)
• Ultrasound of the neck can be used to identify the parathyroid tumor and may identify if there are multiple tumors

Treatment

• Minimally invasive treatment involves injection of the tumor with ethanol (alcohol) under ultrasound guidance. Leakage of the alcohol onto critical structures such as the nerves that control voice box function can result in laryngeal paralysis with devastating effects on breathing. Although this has been reported, the problem has only been temporary, permanent complications are possible.
• Another minimally invasive treatment involves the destruction of the tumor with thermal heat administered via a needle that is inserted into the tumor
• Surgical removal can be performed to remove the tumor. With the surgeon being able to visualize the critical structures surrounding the risk for damage to these structures is minimal. If present, stones located in the bladder are removed at the time of the parathyroid surgery.
• After surgery, the calcium level must be closely watched so that it does not drop to a very low level. This may occurs if the remaining parathyroid glands have gone to "sleep" from the chronic high calcium levels. A low level of calcium in the blood stream can be fatal. Signs of a low calcium level includes rubbing of the face, twitching of muscles, seizures, dilation of the pupils, twitching of the ears, weakness, and loss of appetite. If a low blood calcium level is detected, medication may be prescribed to treat the condition. If the problem is severe, hospitalization may be needed to regulate the calcium level.

Prognosis

• Most patients that do not receive treatment for a parathyroid tumor frequently develop severe kidney failure which can be fatal
• With treatment, your companion can expect to have a normal life span, providing that the tumor is benign