Canine B-cell lymphoma is a highly treatable disease, but cost and logistical factors may hamper an owner’s ability to pursue treatment of their pet with this disease. The authors evaluated the use of single-agent doxorubicin in an intermittent fashion for efficacy in the treatment of this disease. Morphologic and clinical data were analyzed for prognostic significance. Eighteen dogs with B-cell lymphoma, all with multicentric disease, were enrolled. The overall complete response (CR) rate was 78%, median total doxorubicin remission time (TDR) was 80.5 days, and median overall survival (OS) was 169.5 days. The median number of doxorubicin doses administered was 4.5. First remission times were significantly affected by clinical stage and substage of disease. Outcome for the dogs in this study were similar to those previously reported for single-agent doxorubicin treatment. Additionally, the intermittent nature of the treatments made the described protocol more feasible for the owners who enrolled their pets in this study. Intermittent single-agent doxorubicin is not a substitute for multiagent chemotherapy protocols in the treatment of canine lymphoma; however, it is a reasonable alternative if the cost and time commitments are limiting factors for an owner.
The clinical usefulness of computed tomography (CT) as a sole diagnostic modality in identifying disc lesion(s) in chondrodystrophic breeds presenting with acute signs of intervertebral disc disease (IVDD) is incompletely characterized. CT was used prospectively to determine the validity of this tool. Neurologic examinations and CT scans were performed on all dogs at presentation. Surgical decompression was based on those findings. Clinical follow-up examinations were performed on days 1 and 14 postsurgically. CT detected a lesion consistent with clinical findings in 63 of 69 cases (91%). All 63 dogs with Hansen type I IVDD lesions were identified on CT alone. The surgeon and radiologist agreed on lesion level in 72 of 78 lesions (92%) and lateralization in 71 of 78 lesions (91%). Improvement in neurologic grade was documented in 60 of 69 dogs (87%) by 14 days. CT imaging can be used as a single imaging modality in chondrodystrophic dogs presenting with acute paresis. CT used in this manner is a reliable and noninvasive tool for detecting spinal compression secondary to IVDD in chondrodystrophic dogs.
Hemangiosarcomas (HSAs) are aggressive tumors with a high rate of metastasis. Clinical stage has been considered a negative prognostic factor for survival. The study authors hypothesized that the median survival time (MST) of dogs with metastatic (stage III) HSA treated with a vincristine, doxorubicin, and cyclophosphamide (VAC) chemotherapy protocol would not be different than those with stage I/II HSA. Sixty-seven dogs with HSA in different anatomic locations were evaluated retrospectively. All dogs received the VAC protocol as an adjuvant to surgery (n = 50), neoadjuvant (n = 3), or as the sole treatment modality (n = 14). There was no significant difference (P = 0.97) between the MST of dogs with stage III and stage I/II HSA. For dogs presenting with splenic HSA alone, there was no significant difference between the MST of dogs with stage III and stage I/II disease (P = 0.12). The overall response rate (complete response [CR] and partial response [PR]) was 86%). No unacceptable toxicities were observed. Dogs with stage III HSA treated with the VAC protocol have a similar prognosis to dogs with stage I/II HSA. Dogs with HSA and evidence of metastases at the time of diagnosis should not be denied treatment.
Retroperitoneal abscesses, although uncommon, are clinically important. Medical records of seven dogs with naturally occurring retroperitoneal infections from 1999 to 2011 were reviewed to document historical, examination, clinicopathologic, imaging, and surgical findings; etiologic agents; and outcome. Middle-aged sporting dogs were most commonly affected. Dogs were febrile with evidence of either abdominal or lumbar pain. Although traditional radiography can aid in diagnosis, ultrasound appeared to be a more sensitive indicator of disease within the retroperitoneal space. Numerous bacteria were isolated from the abscesses, with anaerobic and facultative anaerobic bacteria being the most commonly isolated. Etiology was largely unknown, but migrating plant material was often suspected. Resolution of the infection required surgical intervention as well as prolonged antibiotic therapy. Although recurrence is possible, outcome can be favorable with no long-term sequela.
A 10 yr old castrated male Siberian husky was evaluated for polyuria, polydipsia, a retroperitoneal mass, and urolithiasis. A marked elevation in Ca was noted on initial blood work, and results of additional testing were consistent with hypercalcemia of malignancy, including an elevated parathyroid hormone-related peptide (PTHrp) value. Based on clinical signs, blood work, diagnostic imaging, and cytology results, unilateral renal neoplasia was suspected. Following a complete right nephrectomy and cystotomy, histopathologic examination confirmed a diagnosis of renal cell carcinoma (RCC). Five days postoperatively, the hypercalcemia had nearly resolved and the PTHrp was zero. This is the first reported case of hypercalcemia of malignancy associated with RCC in a dog.
A 7 yr old castrated male Great Dane presented with a history of progressive myelopathy following the intramuscular injection of melarsomine dihydrochloride 8 wk previously. MRI revealed paraspinal and epidural abscesses at the 13th thoracic (T13) and first lumbar (L1) disc space. The dog’s condition worsened despite medical management, necessitating surgical decompression. Surgical decompression resulted in rapid improvement of the patient’s clinical signs. Histopathologic evaluation of the lesions revealed pyogranulomatous inflammation. Cultures of fluid and tissue within the lesions were negative for bacterial growth, and no infectious organisms were visualized histologically. Melarsomine-associated neurologic signs can be chronic and progressive in nature, presumably secondary to ongoing sterile inflammation that may result in spinal cord compression.
A 13 yr old female spayed Labrador retriever presented for vulvar bleeding. Abdominal radiographs revealed a soft tissue mass in the ventral pelvic canal. A computed tomography (CT) exam and a CT vaginourethrogram localized the mass to the vagina, helped further characterize the mass, and aided in surgical planning. A total vaginectomy was performed and the histologic diagnosis was leiomyoma. Vaginal tumors make up 1.9–3% of all tumors. Seventy-three percent of vaginal tumors are benign, and 83% of those are leiomyomas. Leiomyomas often have a good long-term prognosis with surgical resection. The diagnostic investigation of this case report utilized a multimodal imaging approach to determine the extent and respectability of the vaginal mass. To the best of the authors’ knowledge, this is the first report describing a CT vaginourethrogram.
Veterinary cardiac MRI (cMRI) is a relatively new technique. A dog with recurrent pericardial effusion and a questionable right atrial mass lesion on echocardiography underwent cMRI. cMRI provided excellent anatomic information about the heart and surrounding structures and helped to rule out the presence of a focal mass. A diffuse thickening and enhancement of the pericardium was detected. Pericardiectomy was performed and histopathology revealed a diffuse pericardial mesothelioma. This case illustrates the potential of cMRI in the management of patients with pericardial effusion when echocardiographic findings are equivocal and illustrates cMRI findings in a case of diffuse pericardial mesothelioma.
Pituitary metastases have rarely been recorded in dogs, and to date, none of those reported have been of pancreatic origin. MRI findings are available for only one of those cases. Herein the authors present an 11 yr old English springer spaniel diagnosed with pituitary metastasis of pancreatic origin with a 24 hr history of blindness and only a single lesion on MRI. Neurologic and ophthalmologic examinations localized the lesion to the optic nerves, optic tracts, or optic chiasm. MRI showed a single lesion characterized by a well-circumscribed pituitary mass with extrasellar extension, causing compression of the optic chiasm. Signal intensity was unusual as enhancement could not be appreciated after contrast administration. The dog was euthanized without further diagnostic tests. Histopathologic examination revealed a poorly differentiated exocrine pancreatic carcinoma with widespread metastasis involving the pituitary gland. To the authors’ knowledge, this is the first such case reported in a dog. Pituitary metastases should be included as a differential diagnosis for dogs presenting with acute-onset blindness and for single brain masses affecting the pituitary gland.
An 8 wk old female Dalmatian weighing .56 kg presented with growth retardation. The puppy exhibited no abnormalities during physical examination other than significantly reduced growth compared with her littermates. Endocrine results suggested pituitary dwarfism. Two wk later, the puppy returned due to the onset of megaesophagus, but the puppy unfortunately died the following morning. This case report describes the diagnosis of dwarfism in a Dalmatian puppy that was caused by growth hormone (GH) deficiency and describes its early clinical manifestations.
Two dogs and two cats were evaluated for the acute-onset of abnormal mentation, recumbency, and blindness. All cases had systemic hypertension, ranging from 180 mm Hg to 260 mm Hg. MRI of the brain disclosed noncontrast-enhancing, ill-defined, T2-weighted (T2W) hyperintensities in the white matter of the cerebrum in the areas of the frontal, parietal, temporal, and occipital lobes. Lesions were also observed in the caudate nuclei and thalamus (n = 1 in each). Intracranial hemorrhage was observed in one animal. Diffusion-weighted imaging (DWI) was consistent with vasogenic edema in two animals. Retinal lesions were observed in three animals. Hypertension was secondary to renal disease in three animals. A primary underlying disorder was not identified in one animal. Normalization of blood pressure was achieved with amlodipine either alone or in combination with enalapril. In one cat, hypertension spontaneously resolved. In three cases, neurologic improvement occurred within 24–48 hr of normalization of blood pressure. The presumptive diagnosis of hypertensive encephalopathy was supported by the MRI findings and neurologic dysfunction coincident with systemic hypertension in which the neurologic dysfunction improved with treatment of hypertension. The prognosis appears good for the resolution of neurologic deficits with normalization of blood pressure in animals with hypertensive encephalopathy.
This case report presents two cases of inadvertent intrapleural nasogastric tube (NGT) misplacement with consequent creation of a bronchopleural fistula and the development of an iatrogenic pneumothorax in dogs. Due to the simplicity and relative ease of NGT placement and the lack of reported life-threatening complications in the veterinary literature, the serious risks associated with this procedure are often overlooked. Although pulmonary complications with NGT misplacement have been previously reported in the human literature, serious and potentially fatal complications have not been currently described in veterinary patients. Both of the cases described herein were medically managed with successful outcomes; however, one case was associated with significant morbidity.