Hypertrophic Osteopathy Associated with Disseminated Metastases of Renal Cell Carcinoma in the Dog: A Case Report

Abstract

ABSTRACT. A 6-year-old, mixed breed, intact male dog showed signs of left carpal joint swelling and weakness of the forelimbs one month before presentation. The symptoms gradually progressed to bilateral carpal and tarsal joint swelling and tetraparalysis. There were a number of radiographically identified lytic-proliferative bone lesions noted on the axial skeleton. Hypertrophic osteopathy of the metacarpi and all distal long bones was also evident. Because of the deteriorating quality of life and guarded prognosis, the patient was euthanized and a complete necropsy was performed. Renal cell carcinoma, with metastasis to the lung, thoracic vertebrae, ribs, and the right adrenal gland, was diagnosed. To our knowledge, renal cell carcinoma with bone metastases and hypertrophic osteopathy has not been reported in dogs. KEY WORDS: canine, hypertrophic osteopathy, renal cell carcinoma.J. Vet. Med. Sci. 69(2): 209-212, 2007 Primary renal neoplasia occurs infrequently in dogs, with a prevalence rate of 0.3 to 2% of all canine neoplasia [4,9,10,11,13]. Of these, renal cell carcinoma (RCC) is the most common type [6,9,11,17] and is believed to originate from the epithelium of the proximal convoluted tubules. RCC generally occurs in older (reported average age of 8 years old) male dogs [6,13,16], with no obvious breed predisposition. Here we report an unusual case of canine RCC with disseminated metastases and hypertrophic osteopathy (HO).A 6-year-old, mixed breed, intact male dog was referred for evaluation of tetraparalysis. The patient was not on a regular vaccination program, but was under routine heartworm prevention. A month before presentation, the patient started to show signs of left carpal joint swelling and weakness of the forelimbs. The symptoms gradually progressed to bilateral carpal and tarsal joint swelling and tetraparalysis. An episode of hematuria had also been noted. Upon presentation the patient was anorexic and whining painfully.The patient presented with pale mucosal membranes and was cachexic, with 7% dehydration, tachycardia (150 /min), and tachypenia (60 /min). A right heart murmur was auscultated and graded as IV/VI. The patient was lying on his side, unable to stand or walk, but still with intact neurological reflexes and sensations on all four limbs. The distal parts of all limbs were swollen and firm. Multiple firm masses were palpated under the skin on both sides of the chest wall.Blood tests performed by the referring clinic showed leukocytosis (24300 cells/µl), and normocytic, normochromic anemia (packed cell volume: 27.6%, mean corpuscular volume: 65.7 fl, mean corpuscular hemoglobin: 23.3 pg). The blood total calcium concentration value was within normal limit (8.2 mg/dL). Radiographic findings of the chest showed extensive new bone formation on the bodies of the 4th, 5th, and 6th thoracic vertebrae. Lytic-proliferative bone lesions of variable size were also noted on the right 11th, 13th and the left 4th, 5th, 6th, 12th ribs (Fig. 1), and the upper margin of the right scapula. Exten...

Hypertrophic Osteopathy Associated with Pulmonary Adenosquamous Carcinoma in a Dog

“…Anatomically, the right vagus nerve running ventral to the subclavian artery and continuing caudally along the trachea is adjacent to the right phrenic nerve [3]. At the level of the subclavian artery, the vagus nerve receives branches from the cervicothoracic ganglion which may also supply a branch to the phrenic nerve [3]. In this case, HO might have been caused by vagus nerve stimulation from the affected phrenic nerve.…”

“…In this case, the tumor was not associated with the vagus nerve but had invaded into the right phrenic nerve. Anatomically, the right vagus nerve running ventral to the subclavian artery and continuing caudally along the trachea is adjacent to the right phrenic nerve [3]. At the level of the subclavian artery, the vagus nerve receives branches from the cervicothoracic ganglion which may also supply a branch to the phrenic nerve [3].…”

Systemic Conidiobolus Incongruus Infection and Hypertrophic Osteopathy in a White-Tailed Deer (Odocoileus Virginianus)

“…5,7 Hypertrophic osteopathy is often associated with a neoplastic or granulomatous intrathoracic mass, although hypertrophic osteopathy has been seen and associated with other disease manifestations. 1,7 Hypertrophic osteopathy has been reported in humans, 2 domestic animals, 5 and wild animals, including a roe deer (Capreolus capreolus) with pulmonary abscesses. 12 To the authors' knowledge, this also is the first report of hypertrophic osteopathy in a white-tailed deer.…”

Urinary Tract

“…Tumors can arise from epithelial tissue, mesenchymal tissue, or embryonal tissue of mixed origin. Several paraneoplastic syndromes, including polycythemia, leukocytosis, hypertrophic osteopathy, and hypercalcemia, have been described secondary to renal tumors (Chiang et al, 2007;Durno et al, 2011;Gajanayake et al, 2010;Johnson and Lenz, 2011;Petterino et al, 2011;Peeters et al, 2001). Most primary renal tumors in both dogs and cats consist of malignant epithelial tumors (renal cell carcinomas, transitional cell carcinomas [TCCs], and adenocarcinomas) (Bryan et al, 2006;Gil da Costa et al, 2011;Henry et al, 1999;Ramos-Vara et al, 2003).…”