Carlos H. de M. Souza

Patterns of lymph node metastasis identified following bilateral mandibular and medial retropharyngeal lymphadenectomy in 31 dogs with malignancies of the head

Variable pathways of lymphatic drainage have been described in the dog head and neck. The aim of this study was to retrospectively assess the patterns of lymph node metastasis in dogs with malignancies of the head following bilateral mandibular and medial retropharyngeal lymphadenectomy. Thirty-one dogs were included. Median age at surgery was 10 years (range: 5 months to 14 years) and mean bodyweight was 21.4 ± 11.9 kg. Lymph node metastasis occurred in 14 dogs (45%), with spread to mandibular lymph nodes in 14 dogs and medial retropharyngeal metastasis in 11 dogs. Eight of 13 dogs (62%) with lymphatic metastasis and a lateralised lesion showed contralateral dissemination, while 12/13 (92%) showed ipsilateral metastasis. Of 13 dogs with oral malignant melanoma, four showed metastasis to all four lymph centres. Contralateral metastasis may occur in dogs with malignancies of the head and should be considered during staging and management.

Retrospective Evaluation of Whole Body Computed Tomography for Tumor Staging in Dogs with Primary Appendicular Osteosarcoma

OBJECTIVE To evaluate whole body computed tomography (CT) for staging canine appendicular osteosarcoma. STUDY DESIGN Retrospective case series. ANIMALS Client-owned dogs diagnosed with appendicular osteosarcoma (n=39). METHODS Medical records for client-owned dogs diagnosed with appendicular osteosarcoma from August 2008 to July 2014 were reviewed. Dogs were included if they had a confirmed diagnosis of appendicular osteosarcoma and were staged using whole body CT. Data collected included signalment, body weight, primary tumor location, serum alkaline phosphatase (ALP) activity, findings on 3-view thoracic radiographs, cytologic or histologic results, and findings on CT. RESULTS Thirty-nine dogs (median age 8.5 years; median body weight 37 kg) had osteosarcoma of the distal radius (n=17), proximal humerus (11) and other sites. Serum ALP activity was elevated in 14 dogs. Bone metastasis was not detected in any dog on whole body CT. Pulmonary metastasis was considered definitive on CT based on board certified radiologist assessment in 2/39 dogs (5%). Two additional dogs (2/39, 5%) had soft tissue masses diagnosed on CT, consistent with concurrent, non-metastatic malignancies. CONCLUSION Bone metastases were not identified in any dog with whole body CT. Thoracic and abdominal CT detected lung lesions and concurrent neoplasia in dogs with primary appendicular osteosarcoma. Whole body CT may be a useful adjunct to other screening tests for disseminated malignancy.

Outcome and complications in dogs with appendicular primary bone tumors treated with stereotactic radiotherapy and concurrent surgical stabilization

OBJECTIVE To document the outcome of dogs with appendicular primary bone tumors treated with stereotactic radiotherapy (SRT) and concurrent stabilization. STUDY DESIGN Multi-institutional retrospective case series. ANIMALS Eighteen dogs with presumptive or definitive diagnosis of appendicular osteosarcoma. METHODS Medical records of dogs with appendicular primary bone tumors treated with SRT and stabilization were reviewed for signalment, preoperative staging and diagnostics, radiation dose, stabilization method, and outcome. RESULTS The distal radius was affected in 13/18 cases. Osteosarcoma or sarcoma was confirmed cytologically or histologically in 15/18 cases. Seven dogs were diagnosed with a pathological fracture at the time of treatment, and 11 were considered at high risk for pathological fracture. Dogs received a single dose (n = 5) or 3 doses (n = 13) of SRT. Surgical stabilization was performed under the same anesthetic event as the final dose of SRT in 10 dogs. Stabilization was achieved with a bone plate (n = 15) or interlocking nail (n = 3). Seventeen dogs received adjuvant chemotherapy. Complications occurred in 16/17 dogs, 15/17 of those being considered major complications. Four dogs experienced more than one complication. Infection was the most common complication, diagnosed in 15/17 cases, and considered as a major complication in 13/15 cases. Postoperative fracture was recorded as a major complication in 3 cases. Nine dogs were amputated at a median of 152 days. The median survival time was 344 days. CONCLUSION Treatment of bone tumors with SRT and concurrent stabilization was associated with a prohibitively high complication rate in dogs. Alternative methods for limb salvage should be considered for dogs at risk for pathologic fracture.

Cutaneous iridophoroma in a Green iguana (Iguana iguana )

An 11-year-old intact male Green iguana (Iguana iguana) was referred for treatment of a probable iridophoroma based on previous cytopathology. A periocular mass was present near the right medial canthus. Computed tomography did not show any sign of metastasis. Clinicopathologic abnormalities included lymphopenia and hyperproteinemia. Cytologic and histologic evaluations of the mass were consistent with iridophoroma. Complete surgical excision of the mass was not possible without removal of the orbit due to local tissue involvement. Recovery and suture removal were unremarkable. Adjunctive radiation therapy was recommended, but not performed. A year later, the surgical site had healed well. To our knowledge, this is the first reported chromatophoroma cytopathology in a Green iguana. Chromatophoromas should be included in the differential diagnoses of pigmented skin tumors in reptiles. Early surgical excision is useful to limit local tissue destruction and metastatic potential.

Clinical Response and Adverse Event Profile of Bleomycin Chemotherapy for Canine Multicentric Lymphoma

Although canine multicentric lymphoma is initially responsive to multidrug chemotherapy, resistance and relapse create a need for novel chemotherapeutics. Bleomycin is an antitumor antibiotic with a minimal adverse event profile; though commonly used for human non-Hodgkins lymphoma, its use is poorly characterized in dogs. The purpose of this retrospective case series was to describe the clinical response and adverse event profile of systemic bleomycin for canine multicentric lymphoma (n = 10). A partial response was noted in one dog that died 24 days later due to unrelated disease. Adverse events were infrequent and limited to grade 1 gastrointestinal and grade 1 constitutional toxicity. Although clinical response was minimal, systemic bleomycin was well tolerated when administered at 0.5 U/kg. Additional studies are warranted to determine the influence of administration schedule and dose on the efficacy of bleomycin for veterinary neoplasia.

Outcome after pneumonectomy in 17 dogs and 10 cats: A Veterinary Society of Surgical Oncology Retrospective Study

OBJECTIVE To report the signalment, presenting clinical signs, surgical complications, histologic diagnosis, postoperative complications, and outcome of dogs and cats undergoing pneumonectomy. STUDY DESIGN Retrospective case series; multicenter study. ANIMALS Client-owned dogs (n=17) and cats (n=10). METHODS Signalment, clinical signs, side affected, surgical data, preoperative diagnostic tests (including complete blood count, serum biochemistry, cytologic diagnosis, chest radiographs, and computed tomography), histologic diagnosis, surgical complications, adjunctive therapy, and date and cause of death were collected from records of dogs and cats that underwent pneumonectomy. Survival estimates and complication were assessed. RESULTS Seventeen animals had a left-sided pneumonectomy performed (12 dogs, 5 cats) and 10 animals had a right-sided pneumonectomy (5 dogs, 5 cats). Fourteen animals were diagnosed with neoplasia (52%). The overall incidence of complications for dogs and cats were 76 and 80%, respectively, with major complications in 41 and 50%, respectively. Respiratory complications (persistent pleural effusion, oxygen dependence, persistent increased respiratory rate, or coughing) were the most frequent complications. No animals died or were euthanatized intraoperative or within the first 24 hours postoperative. One dog (6%) and 2 cats (20%) died, or were euthanatized in the first 2 weeks postoperative. CONCLUSION Based on this case series, right and left pneumonectomy can be performed with low perioperative mortality in dogs and cats, with some animals experiencing prolonged survival.

Outcome after pneumonectomy in 17 dogs and 10 cats

OBJECTIVE To report the signalment, presenting clinical signs, surgical complications, histologic diagnosis, postoperative complications, and outcome of dogs and cats undergoing pneumonectomy. STUDY DESIGN Retrospective case series; multicenter study. ANIMALS Client-owned dogs (n=17) and cats (n=10). METHODS Signalment, clinical signs, side affected, surgical data, preoperative diagnostic tests (including complete blood count, serum biochemistry, cytologic diagnosis, chest radiographs, and computed tomography), histologic diagnosis, surgical complications, adjunctive therapy, and date and cause of death were collected from records of dogs and cats that underwent pneumonectomy. Survival estimates and complication were assessed. RESULTS Seventeen animals had a left-sided pneumonectomy performed (12 dogs, 5 cats) and 10 animals had a right-sided pneumonectomy (5 dogs, 5 cats). Fourteen animals were diagnosed with neoplasia (52%). The overall incidence of complications for dogs and cats were 76 and 80%, respectively, with major complications in 41 and 50%, respectively. Respiratory complications (persistent pleural effusion, oxygen dependence, persistent increased respiratory rate, or coughing) were the most frequent complications. No animals died or were euthanatized intraoperative or within the first 24 hours postoperative. One dog (6%) and 2 cats (20%) died, or were euthanatized in the first 2 weeks postoperative. CONCLUSION Based on this case series, right and left pneumonectomy can be performed with low perioperative mortality in dogs and cats, with some animals experiencing prolonged survival.

Outcome After Pneumonectomy in 17 Dogs and 10 Cats: A Veterinary Society of Surgical Oncology Case Series.

OBJECTIVE To report the signalment, presenting clinical signs, surgical complications, histologic diagnosis, postoperative complications, and outcome of dogs and cats undergoing pneumonectomy. STUDY DESIGN Retrospective case series; multicenter study. ANIMALS Client-owned dogs (n=17) and cats (n=10). METHODS Signalment, clinical signs, side affected, surgical data, preoperative diagnostic tests (including complete blood count, serum biochemistry, cytologic diagnosis, chest radiographs, and computed tomography), histologic diagnosis, surgical complications, adjunctive therapy, and date and cause of death were collected from records of dogs and cats that underwent pneumonectomy. Survival estimates and complication were assessed. RESULTS Seventeen animals had a left-sided pneumonectomy performed (12 dogs, 5 cats) and 10 animals had a right-sided pneumonectomy (5 dogs, 5 cats). Fourteen animals were diagnosed with neoplasia (52%). The overall incidence of complications for dogs and cats were 76 and 80%, respectively, with major complications in 41 and 50%, respectively. Respiratory complications (persistent pleural effusion, oxygen dependence, persistent increased respiratory rate, or coughing) were the most frequent complications. No animals died or were euthanatized intraoperative or within the first 24 hours postoperative. One dog (6%) and 2 cats (20%) died, or were euthanatized in the first 2 weeks postoperative. CONCLUSION Based on this case series, right and left pneumonectomy can be performed with low perioperative mortality in dogs and cats, with some animals experiencing prolonged survival.

Surgical management of an odontogenic tumor in a banded Gila monster (Heloderma suspectum cinctum) with a novel herpesvirus.

An adult, 817 g, male, wild-caught banded Gila monster (Heloderma suspectum cinctum) was evaluated during a quarantine examination. The lizard was obtained from the Arizona Game and Fish Department, after capture as a ‘nuisance’ (Sullivan et al. 2004). Physical examination revealed that the Gila monster was mildly underweight and probably mature based on the presence of bilateral nuclear sclerosis and incipient cataracts. An approximately 4 £ 3 mm, broad based, light tan gingival nodule with an irregular surface and unknown depth was identified on the lingual aspect of the cranial right mandible. There was also marked bilateral and symmetric temporal muscle atrophy, of unknown significance. A heparinized whole blood sample was collected, from the ventral coccygeal vein, and submitted for hematologic and biochemical profiles. Blood values were compared to species specific reference ranges from two sources (Cooper-Bailey et al. 2011; International Species Information System 2013). While the majority of values were considered within range per International Species Information System (ISIS), significant hematologic findings according to the study by Cooper-Bailey et al. included a mild leukocytosis (10.0 £ 10/L) with a mild basophilia (1.6 £ 10/L) and moderate azurophilia (2.5 £ 10/L). The biochemical profile was considered unremarkable for the species. At recheck, four months later, the intraoral mass was larger (8 £ 5 mm) (Figure 1(A)). After topical application of 2% lidocaine at 1 mg/kg BW, a fine-needle aspirate of the mass was performed using a 22-gauge hypodermic needle and submitted for cytologic examination. The sample was poorly cellular, but revealed mild atypia of squamous epithelial cells, suggestive of either hyperplasia or squamous cell carcinoma. Repeat bloodwork showed an increasing leukocytosis (13.1 £ 10/L) with a mild basophilia (1.9 £ 10/L) and mild azurophilia (1.5 £ 10/L) according to ISIS ranges, but increased in all cell lines according to Cooper-Bailey et al. Values appeared most consistent with an inflammatory leukogram. Six weeks after initial evaluation, the Gila monster was sedated with midazolam at 0.25 mg/kg BW IM and hydromorphone at 0.1 mg/kg BW IM to collect an incisional biopsy. Topical 2% lidocaine at 2 mg/kg BW was infiltrated around the mass for analgesia. A 5 £ 5 £ 3 mm biopsy was collected from the surface of the mass using curved iris scissors. A portion of the mass was placed in formalin and submitted for histopathologic evaluation. The remaining section was saved frozen for later molecular analysis, utilizing polymerase chain reaction (PCR). A hemostatic sponge, Gelfoam , and topical epinephrine at 0.01 mg/kg BW were applied to the biopsy site to control bleeding. Flumazenil at 0.01 mg/kg BW IM was administered to reverse the effects of midazolam. Histologic findings included anastomosing epithelial cords extending from the gingiva and were considered most consistent with squamous cell carcinoma, with neoplastic cells extending to the sample margins. Given the progression of the mass and the histologic diagnosis, excision with wide margins was elected. A pre-operative, whole body, computed tomography (CT) scan was performed under the same sedation protocol as described above (Figure 2). Findings, considered to be incidental, included three round to angular, well-defined mineral attenuating structures at the caudal aspect of the right shoulder, measuring up to 3 mm in length (consistent with scapulohumeral osteochrondromas) and a focal interruption of the last right lumbar rib (likely an anatomic variation). A single right mandibular tooth appeared to be laterally displaced; while not identified on CT, this appeared to coincide with the mass. No bony changes were appreciated in the right mandible; however, the images were low resolution due to patient size. Dental radiographs may have offered better detail in this case. Five months

What is your diagnosis? Perineal mass in a dog.

A 4-year-old neutered male Catahoula Leopard dog was presented to the University of Florida Small Animal Hospital emergency service for evaluation of a left-side perineal mass. The mass was brought to the owner’s attention when the dog began licking it. The 7 9 6 9 5 cm mass appeared heterogeneous and lobulated on ultrasonographic examination. Two weeks later the dog returned to the oncology service for removal of the mass at which time it had grown to 10 9 8 9 5 cm and was firm, but remained freely moveable. Photomicrographs of the preoperative fine-needle aspirate (FNA) cytology are provided (Figure 1).