Ferret Adrenal Gland Tumors

What are the most common signs?

Signs are usually seen in middle age (3.5 yr) to older ferrets and the most common is alopecia.

Spayed females almost always have vulvar swelling. Males infrequently display dysuria/stranguria. About 30% are puritic. On physical examination, about a third have an adrenal gland large enough to be palpated.

How can I diagnose adrenal gland disease definitively?

A trial of HCG (100 IU IM/repeated in 7-10 d) will rule out ovarian remnants in spayed females or intact females by causing the enlarged vulva to decrease in size. A radiograph almost never shows adrenal gland enlargement although abdominal ultrasound may show enlargement. The best diagnostic assay is measurement of the circulating androgen hormones that the diseased adrenal gland secretes in abundance. This test is currently available only through the University of Tennessee (423)974-5638.

What about ACTH tests or Dexamethasone suppression tests?

These tests are not of use in diagnosing hyperadrenocorticism in ferrets. Normal and diseased ferrets appear to respond the same.

What this disease is NOT?

This disease is not Cushing's disease or Cushing's syndrome. Cortisol is rarely elevated so it is not Cushing's disease. It is adrenal gland disease or hyperadrenocorticism but not Cushing's disease.

What will blood work indicate?

CBC/SMA are often normal. Prolonged disease can produce severe anemia and even pancytopenia. Hypogylcemia can occur if there is a concurrent insulinoma-a frequent occurrence.

How do I treat this condition?

Surgical removal is the preferred treatment. Adrenalectomy techniques are well described in the literature. During the procedure, visualize and palpate both glands because bilateral disease can occur. Other abdominal structures should be evaluated for abnormalities at this time also. If only one adrenal gland is affected, remove it completely. If both are affected, remove one completely and the other only partially. Due to ferret anatomy and proximity of the vena cava, the right sided adrenal gland is more difficult to remove.

What kind of aftercare is required?

In the absence of other underlying conditions, the aftercare is minimal. They rarely require supplemental corticosteroids. Exceptions are abnormal postoperative lethargy and bilateral adrenalectomy cases. We usually give prednisone at 0.5 to 1.0 mg/kg q12 hours or as necessary.

What about medical treatment of this condition?

Mitotane (Lysdodren) has been used with equivical response. Clinical signs may resolve but tend to recur. It has been used when owners cannot afford surgery or the ferret is a poor surgical candidate. We do not give a good prognosis of cure with this treatment. The Mitotane dosage is 50 mg/ferret PO q24 hours for 7 d, followed by maintenance at 50 mg/ferret given every 2-3 days.

Are there any books that can give me further information?

• Biology and Diseases of the Ferret., James G. Fox (1988)
• Ferrets, Rabbits, and Rodents; clinical medicine and surgery. Hillyer and Quesenberry (1996)

Where can I get additional information?

-VIN data base

-Ferrets. Vet Clin N Am - Small Anim Prac 24[1] : 1-23 Jan' 94 Review Article 66 Refs Karen Rosenthal, DVM, MS. The Animal Medical Center; 510 East 62 St., New York, NY 10021

-Hyperadrenocorticism in Ferrets. 4th Mid-West Ex An Med Conf Procd Christine M. Kolmstetter, MS, DVM et al.

-Evaluation of serum estradiol concentrations in alopecic ferrets with adrenal gland tumors. JAVMA 205 [5] : 703-707 Sep'1 94 Clinical Study 15 Refs Robert A. Wagner, VMD and David P. Dorn, VMD Division of Laboratory Animal Resources, University of Pittsburgh, A-115 Scaife Hall, Pittsburgh, PA 15261

-Ultrasonographic detection of adrenal gland tumors in two ferrets. JAVMA 205[7] : 1001-1003 Oct'94 clinical Report 15 Refs Janette Ackermann, DVM; James W. Carpenter, MS, DVM; Cynthia P. Godshalk, DVM, MS; and Craig A. Harms, DVM Dept of Clinical Sciences, College of Veterinary Medicine, Kansas State University Manhattan, KS 66501552-1555 Dec 1'93 Case Report 22 Refs Neil S. Lipman, VMD; Robert P. Marini, DVM; James C. Murphy, DVM, PhD; Zhao Zhibo, DVM; James G. Fox, DVM Division of Comparative Medicine, Massachusetts Institute of Technology' Cambridge, MA 02139.

-Unilateral adrenalectomy as a treatment for adrenocortical tumors in ferrets: five cases (1990- 1992). JAVMA 203[2] : 267-270 Jul 15 '93 Lawrence HJ; Gould WJ; flanders JA; Rowland PH; Yeager AE Dept of Clinical Sciences, New York State College of Veterinary Medicine Cornell University, Ithaca 14853

-Hyperadrenocorticism associated with adrenocortical tumor or nodular hyperpplasia of the adrenal gland in ferrets : 50 cases (1987-1991). JAVMA 203[2] : 271-275 Jul 15'93 Rosenthal KL et.al.