Radiographic features of canine hyperadrenocorticism caused by autonomously functioning adrenocortical tumors: 23 cases (1978-1986)

Radiographic features of 23 dogs with functioning adrenocortical tumors are described. In 56% of the dogs, radiographic detection of adrenomegaly, with or without calcification, was an aid in the diagnosis of adrenocortical neoplasia. Adrenal gland calcification did not distinguish adrenocortical adenoma from carcinoma.     

Results of adrenalectomy in 36 dogs with hyperadrenocorticism caused by adrenocortical tumour

Summary

A total of 38 adrenocortical tumours were removed from 36 dogs with hyperadrenocorticism. The surgical approach was by way of a unilateral flank laparotomy (32 dogs; 14 left and 18 right), a bilateral flank laparotomy (3 dogs) or a midline celiotomy (1 dog).

Two dogs were euthanized during surgery because their tumours could not be resected. Eight dogs died from post‐operative complications. Pancreatic necrosis with peritonitis was the most common cause of death. Eight of the 26 dogs that survived had signs of recurrence of hyperadrenocorticism. Unsuppressible hyperadrenocorticism was found in four dogs; one dog had probably pre‐existent pituitary‐dependent hyperadrenocorticism, and adrenocortical function could not be re‐examined in the remaining three dogs.

Among the 37 tumours examined microscopically expansion of neoplastic tissue into blood vessels was found in 22 of them. Four adrenal glands with adrenocortical tumours also contained phaeochromocytomas. Necropsy was performed in eight dogs. Metastases were found in the lungs of two dogs and in the lungs and liver in one dog.

In combination with the data of previous reports, it is suggested that histological findings in surgery specimens are not good predictors for the clinical outcome.     

Surgical treatment of epulides in dogs: 25 cases (1974-1984)

Epulides were diagnosed and surgically removed in 25 dogs. Histologic examination of the epulides indicated that 40% (10/25) were acanthomatous, 32% (8/25) were ossifying, and 28% (7/25) were fibromatous. Recurrence of the tumor directly resulted in the death of 2 dogs. One of these dogs died of malnutrition 13 months after removal of an ossifying epulis, and regrowth of an acanthomatous epulis that was not resected completely resulted in malnutrition and death in another dog 6 months after surgery. Malignant transformation was observed in a third dog 6 months after removal of an ossifying epulis when an osteosarcoma developed where the epulis had been removed. The range of survival was 6 to 134 months, mean survival time was 43.1 months, median survival time was 49 months, and 1-year survival rate was 92%. Satisfactory long-term tumor control was achieved by aggressive surgical treatment of epulides.     

Plasma cortisol response to exogenous ACTH in 22 dogs with hyperadrenocorticism caused by adrenocortical neoplasia

The plasma cortisol response to exogenous ACTH (ACTH stimulation test) was evaluated in 22 dogs with hyperadrenocorticism caused by adrenocortical neoplasia. The mean basal cortisol concentration (6.3 microgram/dl) was high, but 7 dogs had basal cortisol concentrations that were within normal range. Administration of exogenous ACTH increased the plasma cortisol concentrations in each dog. Normal post-ACTH cortisol concentrations were found in 9 (41%) of the 22 dogs; 13 (59%) had an exaggerated increase in cortisol concentrations after ACTH administration. In 9 of 13 dogs with carcinoma and in 4 of 9 with adenoma, the cortisol response was exaggerated. The mean post-ACTH cortisol concentration in the dogs with carcinoma was approximately 4 times that of the dogs with adenoma; the 7 dogs with the highest concentrations had carcinoma. Repeat studies were performed in 6 dogs 2 to 8 weeks after initial testing. In 5 of the 6 dogs, repeat testing yielded data of similar diagnostic significance. One dog, however, had an abnormally high post-ACTH cortisol concentration at initial evaluation, but had only a minimal response to ACTH administration, with a normal post-ACTH cortisol concentration, at time of resting. Although ACTH stimulation testing is useful in diagnosing hyperadrenocorticism, it can not reliably separate dogs with hyperfunction adrenocortical tumors from clinically normal dogs or from dogs with pituitary-dependent hyperadrenocorticism (bilateral adrenocortical hyperplasia).     

Pulmonic stenosis in the dog: 29 cases (1975-1984)

In a retrospective study of 29 dogs with congenital pulmonic stenosis, we evaluated the clinical, radiographic, angiocardiographic, and cardiac catheterization data. Eighteen dogs had no clinical signs of disease and were referred for evaluation of a previously detected cardiac murmur, 5 dogs had congestive right-sided heart failure, and 5 dogs were examined for exercise intolerance or syncope. Dogs with heart failure tended to be older than dogs without clinical signs of heart failure (19.3 months vs 12 months). All dogs had radiographic or electrocardiographic evidence of right ventricular enlargement. Poststenotic dilatation of the main pulmonary artery and apparent pulmonary undercirculation were observed frequently on survey radiographs. Isolated pulmonic valve dysplasia, representing a range of angiographic pulmonic valve abnormalities, was evident in 88% of the available 26 angiographic studies, whereas subvalvular stenosis was uncommon and observed in only 2 dogs. Muscular hypertrophy of the right ventricular infundibulum and supraventricular crest were observed in 96% and 25% of the angiocardiograms, respectively. Poststenotic dilatation of the main pulmonary artery was observed in every dog. A ratio between the width of the main pulmonary artery and the valve annulus was useful in identifying pulmonic stenosis and distinguishing this anomaly from other congenital malformations. The degree of poststenotic dilatation did not appear to be related to the severity of the systolic pressure gradient, which ranged from 20 to 228 mm of Hg (mean, 93 mm of Hg).(ABSTRACT TRUNCATED AT 250 WORDS)     

Chronic lymphocytic leukemia in the dog: 22 cases (1974-1984)

Chronic lymphocytic leukemia was diagnosed in 22 dogs. Diagnosis was based primarily on detection of lymphocytosis and bone marrow infiltration with small lymphocytes similar to those seen in the blood. More than 50% of the dogs had monoclonal gammopathy, and, of these, 40% had monoclonal light-chain (Bence Jones) proteinuria. Hyperviscosity syndrome was observed occasionally. Most dogs were treated with chemotherapy. For the 17 dogs treated greater than or equal to 30 days, the survival times ranged from 30 to 1,000 days.     

Surgical treatment of idiopathic pericardial effusion in the dog: 25 cases (1978-1993)

Twenty-five cases of canine idiopathic pericardial effusion are described. All were treated surgically and underwent thoracotomy and pericardectomy, with histopathological evaluation of the resected pericardial sac. No tumor, infection, granulation tissue, or foreign body was found. Thirteen of the 25 dogs were golden retrievers, and all were large or giant breeds. Three (12%) died in the immediate postoperative period, and four (16%) died within one year of signs possibly related to the original condition. Eighteen (72%) survived at least 18 months; seven died or were euthanized for reasons unrelated to pericardial effusion (median, 44 months); and 11 were still alive at last contact (median, 61 months).     

Phacofragmentation and aspiration for cataract extraction in dogs: 56 cases (1980-1984)

Fifty-six cases of cataract removal in dogs by phacofragmentation and aspiration were reviewed. Improvement of vision was detected in the immediate postoperative period in 53 (94.6%) of 56 dogs. Vision was present in 25 (85.2%) of 29 dogs evaluated at 2 years after surgery, and in 5 (71.4%) of 7 dogs evaluated 4 years after surgery. Reasons for failure of visual improvement and complications in visual eyes were related primarily to development of postoperative anterior uveitis. Age of the dog at surgery was not a significant factor in the restoration of vision.     

Ultrasonographic features of testicular neoplasia in dogs: 16 cases (1980-1988)

For 16 dogs with testicular neoplasia (n = 19 tumors), ultrasonography was performed to determine whether a correlation exists between ultrasonographic features of testicular tumors and cell type. The echogenicity of the tumors varied depending on the size of the tumor and whether the tumor had focal or diffuse distribution within the testis. The ultrasonographic characteristics of Sertoli cell tumors were variable, with no predominant pattern. This variation may be related to tumor size, because 6 of 7 Sertoli cell tumors were greater than 5 cm in diameter. Focal seminomas and interstitial cell tumors less than 3 cm in diameter had hypoechoic texture. Focal seminomas and interstitial cell tumors greater than 3 cm in diameter had mixed echogenicity. Tumors of multiple cell types were greater than 5 cm in diameter and had mixed echogenicity. In valuable breeding dogs with a small (less than 3 cm) focal intrascrotal lesion, testicular ultrasonography would be of benefit for localization of the mass to the testis or epididymis for subsequent biopsy. In dogs with intraabdominal neoplastic testes, ultrasonography may be of benefit in determining intra-abdominal metastases and invasion of contiguous structures.     

Pulmonic stenosis caused by single coronary artery in dogs: four cases (1965-1984)

Single right coronary artery (CA) associated with pulmonic stenosis was found in 3 English Bulldogs and a Boxer, suggesting a genetic predisposition for the associated anomalies. The left main coronary branch arose from the single right CA, encircled the pulmonic root over hypoplastic pulmonic valves at the level of the obstruction, and appeared to be the primary cause of underlying pulmonic stenosis. Patch-graft surgery to relieve pulmonic stenosis caused death in 1 dog when the unrecognized anomalous CA was served during the procedure. The anomalous left CA was detectable by use of angiocardiography in all 4 dogs and was recognized before surgery in 2 of them. In 1 dog, a right ventricle-to-pulmonary trunk-bridging conduit was implanted to improve outflow from the right side of the heart.     

Secondary intracranial neoplasia in the dog: 177 cases (1986-2003).

BACKGROUND: This study investigates the frequency, location, and clinical findings associated with 177 secondary brain tumors in dogs. HYPOTHESIS: Secondary intracranial neoplasia is more common than primary intracranial neoplasia in dogs during the time period studied, and hemangiosarcoma (HSA) is the most common secondary intracranial tumor. ANIMALS: One hundred and seventy-seven client-owned dogs presented to the Matthew J. Ryan Veterinary Hospital between 1986 and 2003. METHODS: Medical records were searched for a diagnosis of intracranial neoplasia in dogs who underwent complete postmortem examination. Of these dogs, those with a diagnosis of primary intracranial neoplasia were excluded. RESULTS: Of the 177 secondary brain tumors, 51 (29%) were HSAs, 44 (25%) were pituitary tumors, 21 (12%) were lymphosarcomas, and 21 (12%) were metastatic carcinomas. The average age at diagnosis was 9.6 +/- 3.0 years. Most tumors were located in the cerebrum, and a mentation change was the most common presenting clinical sign. On postmortem examination, the same tumor that was in the brain was also present in the lung in 84 cases (47%), in the kidney in 62 cases (35%), and in the heart in 55 cases (31%). CONCLUSIONS AND CLINICAL IMPORTANCE: Secondary intracranial neoplasia in dogs was more common than primary intracranial neoplasia during the time period studied. Many of these dogs had related disease in other body systems that was apparent on diagnostic tests such as thoracic radiography.     

Evaluation of cisplatin-induced emesis in dogs with malignant neoplasia: 115 cases (1984-1987)

A retrospective review of the records of 115 dogs with 13 types of malignant tumors was performed in an attempt to identify factors that influence the degree of emesis observed within 24 hours after cisplatin therapy. Six groups were established on the basis of dosage of cisplatin and on the route of administration: 10 mg/m2 IV (n = 17), 40 mg/m2 IV (n = 10), 50 mg/m2 IV (n = 19), 60 mg/m2 IV (n = 7), 70 mg/m2 IV (n = 36), and 70 mg/m2 intra-arterially (IA; n = 26). Age, gender, weight, dose of cisplatin, route of administration (IV vs IA), and duration of infusion were evaluated. Increasing doses of cisplatin (P less than 0.01) and the IV route of drug administration (P less than 0.0006) were associated with an increased occurrence of vomiting in response to the first treatment. Anesthesia, performed in dogs that were given cisplatin IA, was a confounding variable that may have reduced the emetic potential of the drug after the dogs were awakened. If the dog vomited in response to the first treatment, there was a greater tendency to vomit after subsequent cisplatin treatments (P = 0.08). Multivariable analysis, after correcting for the effects of age, gender, and weight, indicated that high doses of cisplatin (P less than 0.001) and lower weight of the dog (P less than 0.04) were significantly associated with an increased likelihood of vomiting.(ABSTRACT TRUNCATED AT 250 WORDS)     

Surgical treatment of adrenocortical tumors: 21 cases (1990-1996)

Twenty-four adrenocortical tumors were surgically removed from 21 dogs. Histopathological examination confirmed 18 carcinomas and six adenomas. Four dogs died in the perioperative period. Fifteen of the 17 dogs that survived the perioperative period had long-term resolution of their clinical signs. Two dogs with incompletely resected tumors were treated with mitotane to control their clinical signs. Overall median Kaplan-Meier life-table survival for dogs with carcinomas was 778 days (range, one to 1,593 days). Median survival for dogs with adenomas was not reached (range, 11 to 730 days). Histopathological diagnosis, histopathological cellular features, age of the dog, and tumor size were not prognostic of outcome.     

Cryptorchidism and monorchism in cats: 25 cases (1980-1989).

Of 1,345 cats admitted for orchiectomy during a 10-year period, 23 (1.7%) were cryptorchid and 2 (0.1%) were monorchid. Persian cats were over-represented in the cryptorchid population (P = 0.01). Cats were more likely to be unilaterally than bilaterally cryptorchid (P = 0.01). A predisposition for location of undescended testes (abdominal vs inguinal or right vs left side) was not identified in unilateral cryptorchids. All bilateral cryptorchids had abdominally located testes. The most common surgical approaches used for orchiectomy of cryptorchid cats were a caudal ventral midline incision for inguinal testes and a caudal ventral midline celiotomy for abdominal testes.     

Results of excision of thymoma in cats and dogs: 20 cases (1984-2005)

OBJECTIVE: To provide long-term follow-up information for a series of dogs and cats with invasive and noninvasive thymomas treated by excision alone. DESIGN: Retrospective case series. ANIMALS: 9 cats and 11 dogs with thymoma. PROCEDURES: Medical records were reviewed. The following factors were analyzed for their effect on prognosis: age of dog or cat, invasiveness of the tumor, percentage of lymphocytes in the mass (percentage lymphocyte composition) on histologic evaluation, and mitotic index of the mass. RESULTS: All patients were treated with excision of the tumor alone. Median overall survival time for the cats was 1,825 days, with a 1-year survival rate of 89% and a 3-year survival rate of 74%. Median overall survival time for the dogs was 790 days, with a 1-year survival rate of 64% and a 3-year survival rate of 42%. Recurrence of thymoma was observed in 2 cats and 1 dog, and a second surgery was performed in each, with subsequent survival times of 5, 3, and 4 years following the first surgery. Percentage lymphocyte composition of the mass was the only factor that was significantly correlated with survival time; animals with a high percentage of lymphocytes lived longer. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study indicated that most cats and dogs with thymomas did well after excision. Even cats and dogs with invasive masses that survived the surgery and the few cats and dogs with recurrent thymomas or paraneoplastic syndromes had a good long-term outcome. Excision should be considered an effective treatment option for dogs and cats with thymomas.     

Use of radiotherapy for the treatment of intranasal tumors in cats: six cases (1980-1985)

Six cats with intranasal neoplasia treated with radiotherapy were evaluated. The mean survival time from the initiation of radiotherapy was 19 months, with 2 cats still known to be alive. Two cats died for reasons unrelated to the primary tumor. One cat had no clinical evidence of nasal tumor 41 months after treatment, but was lost to further follow-up evaluation.     

Comparison of surgical and nonsurgical treatment of humeral fractures in horses: 22 cases (1980-1989).

Medical records of 22 horses with humeral fractures were reviewed. The horses were from 2 to 144 months old (mean, 25.8 +/- 37.3 months). Ten horses were treated with stall confinement, 3 were treated surgically, and 9 were euthanatized at the time of diagnosis. Seven of 10 horses treated nonsurgically (stall confinement) were able to be ridden 5 to 12 months after the diagnosis was made (mean, 7.5 +/- 2.6 months). One horse treated nonsurgically was euthanatized 6 months after diagnosis because of laminitis in the contralateral limb. Two horses treated nonsurgically were lost to follow-up evaluation. Two of the 3 horses treated surgically had fractures repaired with Rush pins. The fractured humerus of the third horse was repaired with lag screws. Of the 3 surgically treated horses, 1 was pasture sound 10 months after surgery, but developed varus deviation in the contralateral carpus 6 weeks after repair; 1 horse was euthanatized 2 weeks after surgery because of failure of the implant; and the other horse was sound for riding 10 months after surgery. On the basis of these findings, young horses with humeral fractures that are treated nonsurgically can become sound for riding.     

Adrenal necrosis in a dog receiving trilostane for the treatment of hyperadrenocorticism

Clinical and biochemical changes suggestive of hypoadrenocorticism were observed in a 10-year-old male neutered Staffordshire bull terrier shortly after beginning therapy with trilostane for the treatment of hyperadrenocorticism. The dog's condition was stabilised with intravenous fluids, fludrocortisone and prednisolone. An exploratory laparotomy and excisional biopsy of the left adrenal gland were performed. Histopathological analysis showed adrenal cortical necrosis with reactive inflammation and fibrosis. Trilostane is a reversible inhibitor of steroid synthesis and this complication has not been reported previously. Clinicians should be aware that trilostane therapy may result in adrenal necrosis but that prompt treatment might correct a life-threatening situation.     

Hypokalemia in cats: 186 cases (1984-1987)

Retrospective review of serum biochemical data obtained from 501 cats over a 3-year period (1984-1987) indicated that 186 (37%) had hypokalemia (serum potassium concentration less than 4.1 mEq/L). After adjusting for disease diagnosis, cats fed either of 2 commercial diets were 4 times more likely to be hypokalemic than cats fed other diets. Odds ratios (OR; measure of association), adjusted for diet type, were calculated to determine the odds of hypokalemia for a given disease, compared with odds of normokalemia for the same disease. Chronic renal failure (OR = 14.4), hepatic disease (OR = 5.7), systemic infectious diseases (viral or bacterial; OR = 2.7), and neuromuscular or CNS disease (OR = 2.4) were all significantly associated (P less than 0.05) with the occurrence of hypokalemia. Significant differences in age or sex between hypokalemic and normokalemic cats were not found. Within the group of 186 hypokalemic cats, hypercholesterolemia (89 cats; 48%), hyperglycemia (88 cats; 47%), high serum urea nitrogen concentration (86 cats; 46%), hyperchloridemia (80 cats; 43%), and high serum creatinine concentration (73 cats; 39%) were the most common biochemical abnormalities. When disease diagnosis was compared among cats with severe hypokalemia (serum potassium concentration less than 3.0 mEq/L) and those with moderate hypokalemia, cats with severe hypokalemia were 3.5 times more likely to have chronic renal failure than cats with less severe hypokalemia.(ABSTRACT TRUNCATED AT 250 WORDS)