Idiopathic hemorrhagic pericardial effusion with organized thrombi in a dog

A dog was examined because of cardiac tamponade secondary to pericardial effusion. Masses adjacent to the right atrial and ventricular walls were revealed by echocardiography. Pericardectomy and biopsies of the masses established the diagnosis of idiopathic hemorrhagic pericardial effusion with organized thrombi. The dog was healthy 3 months after surgery. These organized thrombi mimicked cardiac neoplasia echocardiographically, and such a possibility should be included in the list of differential diagnoses of cardiac masses.     

Two chondrosarcomas in the urethra of a German shepherd dog

An eight-year-old, male castrated German shepherd dog was presented with signs consistent with urinary obstruction. Cystoscopy and contrast radiography showed two distinct urethral masses. Penile amputation and perineal urethrostomy were performed to alleviate the clinical signs. Histopathology of the masses revealed two low-grade chondrosarcomas. At the time of writing, 18 months after surgery, the dog remained disease free.     

Simultaneous hyperplasia, metaplasia, and neoplasia in an 8 year-old boxer dog: a case report

Generalized gingiva hyperplasia and multiple gingival masses were observed in an 8 year-old boxer dog. The masses were removed surgically. Three of them were biopsied. Microscopic examination was reported as fibrous gingival hyperplasia, fibrous epulis with osseous metaplasia, and mast cell tumor. Twenty-two months following surgery, moderate generalized gingival hyperplasia was present, with no clinical evidence of regrowth of the neoplasms.     

Pancreatic mixed acinar-endocrine carcinoma in a dog

A 10.5‐year‐old crossbreed dog was presented with a history of hypoglycaemic episodes and elevated serum insulin concentration. A pancreatic mass was removed at surgery along with an enlarged draining lymph node. An unresectable hepatic nodule was also present. Immunohistochemistry confirmed the pancreatic and lymph node masses as functional mixed acinar‐endocrine carcinoma, previously unreported in domestic species. Persistent hypoglycaemia and hyperinsulinaemia post‐operatively was highly suggestive of the hepatic mass being a functional metastasis. The dog was managed on prednisolone and remained asymptomatic 9 months post‐operatively. This tumour type has only been rarely reported in human patients and may highlight the need for more rigorous immunohistochemical staining of pancreatic masses in veterinary species to identify the prevalence of this tumour type.     

Surgical excision of ectopic thyroid carcinoma involving the base of the tongue in dogs: three cases (1980-1987)

Localized thyroid carcinoma involving the base of the tongue was diagnosed in 3 dogs examined because of a midline cervical mass rostroventral to the larynx. These masses had been present for 4 to 12 months and were firm, nonsensitive, and fixed in position. One dog had progressive dysphagia and dyspnea. Masses were surgically excised together with the base of the tongue and portions of the hyoid apparatus. Severe dyspnea that developed immediately after surgery in 1 dog was managed by tracheostomy intubation for 4 days. Transient dysphagia developed in all dogs. Hydration was maintained by IV fluid administration until water and food of gruel consistency could be swallowed 1 to 6 days after surgery. Consistency of food was gradually thickened to normal, as swallowing improved 6 days to 2 months after surgery. One dog developed aspiration pneumonia that resolved after antimicrobial administration and improved swallowing that prevented further aspiration. After 9 months, 3 years, and 6 years, the dogs were clinically normal.     

CONTRAST-ENHANCED COMPUTED TOMOGRAPHY AS A PREOPERATIVE INDICATOR OF VASCULAR INVASION FROM ADRENAL MASSES IN DOGS

The purpose of this study was to determine if contrast-enhanced computed tomography (CT) accurately reflected vascular luminal invasion by adrenal masses in dogs. Medical records of 15 dogs with 17 adrenal masses that underwent preoperative CT imaging were reviewed. Presence or absence of vascular invasion was confirmed by surgery or necropsy/histology. Vascular invasion was identified correctly using contrast-enhanced CT in 11/12 dogs. The sensitivity and specificity of contrast-enhanced CT for vascular invasion compared with surgery or necropsy was 92% and 100%, respectively. The positive predictive value and negative predictive value of contrast-enhanced CT was 100% and 90%, respectively. The accuracy was 95%. In one dog, invasion of the phrenicoabdominal vein was not identified on CT images. Six of eight masses with vascular invasion where a histologic diagnosis was obtained were malignant. Four of four pheochromocytomas invaded adjacent vasculature. Contrast-enhanced CT provided accurate preoperative assessment of adrenal masses. Vascular invasion by adrenal masses in this study occurred by way of the lumen of the phrenicoabdominal vein with subsequent intraluminal extension into other veins, rather than by erosion through vessel walls.     

NODULAR FAT NECROSIS IN THE FELINE AND CANINE ABDOMEN

The radiographic appearance of nodular fat necrosis is described in ten cats and one dog. The most common radiographic sign was the presence of a focal mineralized circular to oval soft tissue mass in the abdominal fat as present in 9 cats. These masses had a distinct eggshell-like rim encapsulating the lesion. In one cat and one dog multiple masses were present, without radiographic signs of mineralization. Abdominal ultrasound was performed in three cats and one dog, findings included the presence of hyperechoic masses with associated acoustic shadowing, some with a hypoechoic centre. Almost all animals were old and obese. In three cats and one dog, changes were confirmed with biopsy or post mortem examination. Lesions having the appearance of those in this paper are most likely incidental findings and should not be confused with abdominal masses of neoplastic origin. Ultrasound can be helpful in identifying such lesions.     

Uterine Leiomyoma in a Spayed Poodle Bitch: A Case Report

A 16‐year‐old, spayed, female poodle dog was presented for evaluation of tenesmus, with the ability to attract male dogs and a willingness to mate. The dog had undergone an ovariohysterectomy when it was 7 years old. Haematological and serum biochemistry analyses demonstrated leucocytosis and a mild uraemia. A vaginal smear was predominantly made up of superficial cells, accounting for at least 80% of the cells. Abdominal ultrasonography revealed a heterogeneous multicystic mass at the caudal abdomen and two masses with anechoic areas adjacent to the caudal pole of each kidney. A midline exploratory laparotomy identified a uterine mass and residual ovaries that were surgically excised. Histopathological examination of the mass demonstrated that it was a leiomyoma. The left ovary had a cystic structure and the right ovary had a papillary cystic adenoma. Seven months after the surgery, the owner reported that the dog was clinically normal. To the authors’ knowledge, this is the first reported case of a uterine leiomyoma after an incomplete ovariohysterectomy in the dog.     

Bone haemangio-sarcoma in a young Belgian malinois

Bone haemangiosarcoma in a young Belgian malinois initially presented as an abscess involving the Tight 10th rib. The dog responded promptly to abscess drainage and antibiotics. Anaemia and thrombocytopenia began one week later and ultrasonography revealed splenic and liver lesions. Exploratory surgery identified tumour masses in the spleen, liver, lung and rib. Histopathological diagnosis was hemangiosarcoma, possibly of bone origin.     

Papillary ovarian cystadenocarcinoma in a dog

An 11-year-old female German Shepherd dog was presented for investigation of progressive enlargement of the abdomen, periodic bloody discharge from the vulva and rapid exhaustion. Transabdominal ultrasonography and lateral abdominal radiography demonstrated an echogenic formation with anechogenic cavities located cranial to the urinary bladder and a homogeneous shadow with an elliptical shape was located caudal to the rib arc. Both showed indistinct borders. Exploratory laparotomy identified bilateral ovarian masses and ovariohysterectomy was performed. Histopathology confirmed ovarian cystadenocarcinoma. The dog remained clinically normal without evidence of metastatic disease 4 months after surgery. Papillary cystadenocarcinoma in the bitch could affect both ovaries and manifests with a rapid growth rate and clinical signs such as rapid exhaustion, abdominal enlargement and vulval discharge. Ovariohysterectomy is the treatment option.     

Imaging diagnosis--cervical spine chondroma in a dog

An extradural chondroma originating in the cervical spine was diagnosed in an 8-year-old, intact male Chow-Chow that presented acute cervical pain and chronic right thoracic limb lameness. Myelographic images were within normal limits. With magnetic resonance (MR) imaging, an extradural mass was identified at the level of the C4-C5 vertebrae. This mass was excised, and the histologic diagnosis was chondroma. Fifteen months after surgery, the dog was clinically normal, and no regrowth of the mass was identified on follow-up MR images. Spinal chondromas are rare tumors in the dog, but should be considered as a rule out for contrast-enhancing extradural vertebral masses.     

Ventral surgical approach to the caudal brain stem in dogs

OBJECTIVE: To develop a safe neurosurgical procedure that accessed the ventral pons and medulla of the dog primarily for the removal of brain stem neoplasms. STUDY DESIGN: In vivo study. METHODS: A cadaver study was performed on mesocephalic dog heads to develop a neurosurgical approach to the ventral brain stem. Based on this study, an approach to the ventral brain stem was developed by basioccipital craniectomy. This procedure was performed on 4 young neurologically normal Beagle dogs to assess morbidity and mortality associated with the procedure. Morbidity was evaluated by subjective criteria, daily complete neurologic examinations, comparison of preoperative and postoperative brain stem auditory evoked response (BAER) tests, and postmortem examinations. RESULTS: Three dogs developed a transient cough but were neurologically normal after surgery. One dog was euthanatized within 12 hours of surgery because of severe postoperative morbidity associated with basilar artery disruption due to improper development of the craniectomy. Prolongations of postoperative BAER latencies were observed in 2 dogs but did not appear to be associated with clinical deficits or histopathologic changes in the brain stem. Minimal histopathologic changes were observed except in the dog with basilar artery disruption. Results of this study indicate that, although technically challenging, this procedure can be performed with minimal morbidity. CLINICAL IMPLICATIONS: The main indication for this procedure is surgical reduction or biopsy of ventrally located brain stem neoplasms in dogs. The major disadvantage is anatomic restrictions that prevent access to laterally oriented ventral brain stem masses.     

Clinical usefulness of post-operative 18F-fluorodeoxyglucose positron emission tomography-computed tomography in canine hemangiosarcoma

This report describes the usefulness of positron emission tomography-computed tomography (PET-CT) for evaluating recurrent or residual tumors following surgery. CT and ¹⁸F-fluorodeoxyglucose PET-CT were pre- and post-operatively applied to multiple masses in a dog with hemangiosarcoma. The distinction between the left subcutaneous mass and the peritoneum was clarified on pre-operative CT examination, and malignancy was suspected based on PET-CT. A recurrent or residual tumor in the left subcutaneous region was suspected on post-operative PET-CT, and confirmed through histopathologic examination.     

Multiple meningiomas in three dogs

Three dogs with seizures were diagnosed with multiple intracranial meningiomas. Two of the three dogs were golden retrievers, and ages ranged from 9 to 11 years. Treatment consisted of surgery and radiation (n=2) or chemotherapy (n=1). In all three cases, the masses were two distinct tumors as determined by imaging, surgery, or necropsy. In two dogs, the meningiomas had the same histological pattern, while in one dog the histological subtypes were different.     

Tumoral calcinosis in a dog with chronic renal failure

A 2-year-old male German shepherd dog in poor bodily condition was evaluated for thoracic limb lameness due to a large, firm mass medial to the left cranial scapula. Radiography revealed several large cauliflower-like mineralized masses in the craniomedial left scapula musculature, pectoral region and bilaterally in the biceps tendon sheaths. Urinalysis, haematology and serum biochemistry showed that the dog was severely anaemic, hyperphosphataemic and in chronic renal failure. The dog was euthanased and a full post mortem performed. A diagnosis of chronic renal failure with secondary hyperparathyroidism was confirmed. The mineralised masses were grossly and histopathologically consistent with a diagnosis of tumoral calcinosis. Tumoral calcinosis associated with chronic renal failure that does not involve the foot pads is rarely seen.     

Massive midline occipitotemporal resection of the skull for treatment of multilobular osteochondrosarcoma in two dogs

CASE DESCRIPTION: Two 6-year-old male dogs were evaluated for removal of midline occipito-temporal multilobular osteochondrosarcomas. CLINICAL FINDINGS: Physical examination revealed mild ataxia in 1 dog and large masses of the central occipitotemporal portion of the skull in both dogs. Computed tomography, magnetic resonance imaging (MRI), or both revealed large bone-origin occipitotemporal masses with impingement of the brain and the sagittal and transverse venous sinuses. Three-dimensional contrast magnetic resonance image reconstruction delineated collateral venous circulation around the tumor and venous sinus occlusion in 1 dog. TREATMENT AND OUTCOME: Tumors in both dogs were surgically removed and the skull defects repaired with polymethyl methacrylate prostheses. Twenty-four hours after surgery, 1 dog had normal mentation, cranial nerve function, and conscious proprioceptive responses, whereas the other dog had depressed mentation but no neurologic deficits. Both dogs were discharged 4 days after surgery with normal mentation and no neurologic deficits. CLINICAL RELEVANCE: Findings suggested that MRI and computed tomography can play a key role in assessment of essential cortical collateral circulation when surgical removal of tumors is likely to result in bilateral disruption of transverse venous sinuses. Without robust collateral circulation and proper preoperative planning, removal of massive skull tumors in the midline occipitotemporal region will likely result in substantial morbidity or death. However, results in the 2 dogs reported here indicate the feasibility of removing such tumors with good outcomes in the presence of well-developed collateral venous drainage.     

Non-skeletal multicentric chondrosarcoma in the hindlimb of a dog

An eight-year-old, spayed, female golden retriever was presented with progressive right hindlimb lameness and polyuria/polydipsia. Multiple soft tissue masses were palpable within the hindlimb muscles. A tentative diagnosis of sarcoma was made on fine needle aspiration. A computed tomography scan of the hindlimb and thorax confirmed the presence and location of the masses, none of which were associated with the bones of the hindlimb. In addition, two pulmonary lesions were identified in the right cranial lung lobe. A diagnosis of chondrosarcoma was confirmed on histopathology with a final diagnosis of extraskeletal chondrosarcoma. A high, hindlimb amputation was performed, and chemotherapy was initiated. Polyuria and polydipsia resolved 2 weeks postoperatively. Numerous lung lesions, suspected to be metastases were found on routine followup radiographs, 73 days post surgery after which the dog was lost to follow-up.     

Video‐Assisted Thoracoscopic Resection of Noninvasive Thymomas Using One‐Lung Ventilation in Two Dogs

Objective— To report the technique and outcome of video‐assisted thoracoscopic surgery (VATS) for resection of cranial mediastinal thymoma in 2 dogs. Study Design— Case report. Animals— Eleven‐year‐old Labrador Retrievers (n=2). Methods— Two dogs had VATS resection of thymoma. Preoperative computed tomography (CT) scans revealed well‐circumscribed cranial mediastinal masses with dimensions of 4.5 cm × 4.2 cm × 3.7 cm and 2.1 cm × 2.1 cm × 4.1 cm (at the time of resection) without CT evidence of vascular invasion. One‐lung ventilation (OLV) was achieved using a bronchoscopically placed double‐lumen endobronchial tube. A 3‐portal technique was used for VATS access to the thorax. Thymomas were dissected from the tissues of the cranial mediastinum with the aid of a harmonic scalpel and retrieved in specimen retrieval bags. Results— Two cranial mediastinal thymomas were resected successfully, with their capsules intact, using a VATS technique. One dog developed aspiration pneumonia postoperatively which resolved with treatment and remains healthy 18 months postoperatively with no radiographic evidence of tumor recurrence. The second dog was diagnosed with myasthenia gravis, megaesophagus, and aspiration pneumonia preoperatively and despite recovering well from the procedure had a second episode of aspiration pneumonia 5 days postoperatively and was euthanatized. Conclusions— VATS resection of modestly sized noninvasive thymoma is possible in dogs. Careful case selection and preoperative imaging are the keys. Clinical Relevance— Thoracoscopic resection of modestly sized mediastinal masses forms part of an increasingly expansive set of indications for minimally invasive surgery in select veterinary patients.     

Percutaneous ultrasound-guided chemical parathyroid ablation for treatment of primary hyperparathyroidism in dogs.

OBJECTIVE: To evaluate the efficacy, feasibility, and safety of ultrasound-guided chemical ablation of parathyroid masses in dogs with primary hyperparathyroidism. DESIGN: Prospective clinical trial. ANIMALS: 8 dogs. PROCEDURE: In all dogs, a solitary parathyroid mass was evident ultrasonographically. Dogs were anesthetized with propofol, and a 27-gauge needle was directed into the parathyroid mass under ultrasound guidance. Ethanol (96%) was injected into the mass until there was evidence of diffusion of fluid throughout the mass. Serum total calcium, ionized calcium, phosphorus, and parathyroid hormone (PTH) concentrations were monitored daily for 5 to 7 days after the ablation procedure and again 1, 3, and 6 months after the procedure. Dogs were also monitored for adverse effects. Follow-up ultrasonography was performed 5 days and 1 month after the ablation procedure. RESULTS: One injection was required in 7 dogs, and 2 injections were required in 1. Serum total and ionized calcium concentrations were within reference ranges within 24 hours after treatment in 7 dogs and within 5 days in 1 dog. Serum PTH concentration decreased and serum phosphorus concentration increased within 24 hours after treatment in all 8 dogs. Transient hypocalcemia developed in 4 dogs during the first 5 days after treatment, but only 1 dog required treatment for hypocalcemic tetany. Hypercalcemia recurred in 1 dog 1 month after the procedure and surgical removal of the parathyroid mass was required. Other adverse effects were not reported. CONCLUSIONS AND CLINICAL RELEVANCE: Ultrasound-guided chemical ablation of parathyroid masses is a safe and effective alternative to surgery for dogs with primary hyperparathyroidism.     

Peliosis hepatis in a dog infected with Bartonella henselae

A 6-year-old spayed female Golden Retriever was examined because of generalized weakness and abdominal distention. Abdominal ultrasonography revealed a large quantity of peritoneal fluid. In addition, the liver appeared larger than normal and contained multiple, small, nodular masses and cyst-like structures. Abdominal exploratory surgery was performed, and 5 L of serosanguineous peritoneal fluid was removed. Gross lesions were not found in the stomach, kidneys, intestines, adrenal glands, or urinary bladder. There were diffuse cystic nodules in all liver lobes. The dog did not recover from anesthesia. A diagnosis of peliosis hepatis was made on the basis of gross and histologic appearance of the liver. A polymerase chain reaction assay revealed Bartonella henselae DNA in liver specimens. To our knowledge, this is the first report of molecular evidence of B henselae infection in a dog with peliosis hepatis.