The effect of prednisone on histologic and gross characteristics in canine mast cell tumors.

The objective of the study was to determine whether neoadjuvant prednisone therapy affects histological features of cutaneous and subcutaneous mast cell tumors. Twenty-eight dogs with a treatment naïve > 1-cm diameter mast cell tumor (MCT) were randomly assigned (Random number generator; Random.org, Dublin, Ireland) in a blinded fashion to receive either prednisone or placebo (Quality Food Center Pharmacy, Kirkland, Washington, USA). Volumes of mast cell tumors were calculated before incisional and excisional biopsies. Following incisional biopsy, patients received either prednisone (1 mg/kg body weight) daily or a placebo for 7 to 14 days leading up to excisional biopsy. Tumor grade for cutaneous MCT, and mitotic count and atypia for all tumors were reported. Perioperative treatment with prednisone had no significant effect on tumor grade, atypia, or mitotic count. Tumor volume was significantly decreased with prednisone treatment. The use of neoadjuvant prednisone to decrease MCT volume in order to facilitate tumor excision, can be considered without significant concern for change of tumor histologic features in the common population of low- to intermediate-grade MCT.

Effet de la prednisone sur les caractéristiques histologiques et macroscopiques des mastocytomes canins. L'objectif de la présente étude était de déterminer si une thérapie néoadjuvante avec de la prednisone affecte les caractéristiques histologiques des mastocytomes cutanés et sous-cutanés. Vingt-huit chiens avec un mastocytome (MCT) ayant un diamètre > 1 cm avant le traitement furent répartis de manière aléatoire (Random number generator; Random.org, Dublin, Irlande) à l'aveugle pour recevoir soit de la prednisone ou un placebo (Quality Food Center Phamacy, Kirkland, Washington, USA). Les volumes des MCT furent calculés avant les biopsies d'incision et d'excision. À la suite des biopsies d'incision, les patients reçurent soit de la prednisone (1 mg/kg de poids corporel) quotidiennement ou un placebo pour 7 à 14 jours menant à la biopsie d'excision. Le grade des tumeurs pour les MCT cutanés, ainsi que le dénombrement mitotique et l'atypie pour toutes les tumeurs furent rapportés. Le traitement préopératoire avec de la prednisone n'a pas eu d'effet significatif sur le grade des tumeurs, l'atypie ou le dénombrement mitotique. Le volume des tumeurs était réduit significativement avec le traitement à la prednisone. L'utilisation néoadjuvant de prednisone afin de diminuer le volume des MCT dans le but de faciliter l'excision des tumeurs peut être considérée sans préoccupation significative pour des changements dans les caractéristiques histologiques des populations habituelles de MCT de grade bas à intermédiaire.(Traduit par Dr Serge Messier).

Comparison of complications and outcome following unilateral, staged bilateral, and single-stage bilateral ventral bulla osteotomy in cats.

OBJECTIVE: To compare complications and outcome following unilateral, staged bilateral, and single-stage bilateral ventral bulla osteotomy (VBO) in cats. ANIMALS: 282 client-owned cats treated by VBO at 25 veterinary referral and academic hospitals from 2005 through 2016. PROCEDURES: Medical records of cats were reviewed to collect information on signalment, clinical signs, diagnostic test results, surgical and postoperative management details, complications (anesthetic, surgical, and postoperative), and outcome. Associations were evaluated among selected variables. RESULTS: Unilateral, staged bilateral, and single-stage bilateral VBO was performed in 211, 7, and 64 cats, respectively, representing 289 separate procedures. Eighteen (9%), 2 (29%), and 30 (47%) of these cats, respectively, had postoperative respiratory complications. Cats treated with single-stage bilateral VBO were significantly more likely to have severe respiratory complications and surgery-related death than cats treated with other VBO procedures. Overall, 68.2% (n = 197) of the 289 procedures were associated with Horner syndrome (19.4% permanently), 30.1% (87) with head tilt (22.1% permanently), 13.5% (39) with facial nerve paralysis (8.0% permanently), and 6.2% (18) with local disease recurrence. Cats with (vs without) Horner syndrome, head tilt, and facial nerve paralysis before VBO had 2.6, 3.3, and 5.6 times the odds, respectively, of having these conditions permanently. CONCLUSIONS AND CLINICAL RELEVANCE: Findings suggested that staged bilateral VBO should be recommended over single-stage bilateral VBO for cats with bilateral middle ear disease. Cats with Horner syndrome, head tilt, and facial nerve paralysis before surgery were more likely to have these conditions permanently following surgery than were cats without these conditions.

Congenital sternal defect repair in an adult cat with incomplete pentalogy of Cantrell.

CASE DESCRIPTION: A 1-year-old spayed female domestic shorthair cat was evaluated for a sternal defect and ventral abdominal wall hernia. CLINICAL FINDINGS: The cat appeared healthy. Palpation revealed a sternal defect, and the heart could be observed beating underneath the skin at the caudoventral aspect of the thorax. A 3-cm-diameter freely movable mass, consistent with a hernia, was also palpated at the cranioventral aspect of the abdomen. Thoracic radiographic and CT images revealed a sternal cleft, cranial midline abdominal wall hernia, and peritoneopericardial diaphragmatic hernia (PPDH). TREATMENT AND OUTCOME: Thoracotomy and celiotomy were performed. The sternal cleft was repaired with a porcine small intestinal submucosa graft, titanium contourable mesh plate, and interrupted 25-gauge cerclage wires. A diaphragmatic herniorrhaphy was used to correct the PPDH. Thoracic radiographs were obtained immediately after surgery to confirm repair of the sternal cleft, abdominal wall hernia, and PPDH and at 1 and 3 months after surgery to assess the surgical implants, which had not migrated and were intact with only mild bending at the cranial and caudal margins of the mesh plate. At both recheck examinations, the cat appeared healthy with no complications reported by the owner. CLINICAL RELEVANCE: A novel surgical technique was used to successfully repair a large sternal cleft in an adult cat with no postoperative complications reported. This technique may be useful for the treatment of sternal clefts in other cats. This was the first report to describe an adult cat with congenital defects consistent with incomplete pentalogy of Cantrell.

Primary appendicular hemangiosarcoma and telangiectatic osteosarcoma in 70 dogs: A Veterinary Society of Surgical Oncology retrospective study.

OBJECTIVE: To define and compare clinical characteristics of canine primary appendicular hemangiosarcoma (HSA) and telangiectatic osteosarcoma (tOSA), including signalment, presentation, response to treatment, and prognosis. STUDY DESIGN: Multi-institutional retrospective study. ANIMALS: Seventy dogs with primary appendicular HSA or tOSA. METHODS: Patient data were obtained from institutions' medical records. Immunohistochemistry was applied to archived tissues to establish tumor type. Patient characteristics, treatment responses, and outcomes were described and compared by tumor type. RESULTS: Forty-one HSA and 29 tOSA were identified. Dogs with HSA were more likely than dogs with tOSA to be male and have hind limb tumors; 78% of HSA occurred in hind limbs, particularly the tibia. Dogs with tOSA weighed a median of 9.9 kg (95% CI 4.6-15.3) more than dogs with HSA. Most dogs received antineoplastic treatment, predominantly amputation with or without adjuvant chemotherapy. Overall survival with local treatment and chemotherapy was 299 days (95% CI 123-750) for HSA and 213 days (95% CI 77-310) for tOSA. Younger age and more aggressive treatment were associated with longer survival in dogs with HSA but not tOSA. One-year survival rates did not differ between dogs with HSA (28%) and those with tOSA (7%). CONCLUSION: Distinct clinical features were identified between HSA and tOSA in this population. Both tumors were aggressive, with a high incidence of pulmonary metastases. However, local treatment combined with chemotherapy led to an average survival 7 months for tOSA and 10 months for HSA. CLINICAL SIGNIFICANCE: HSA should be considered as a differential in dogs with aggressive lytic bone lesions, particularly medium-sized dogs with tibial lesions. HSA has a unique clinical presentation but similar therapeutic response and outcome to OSA. Amputation and chemotherapy appear to prolong survival in some dogs with HSA and tOSA.

Comparison of thoracic duct ligation plus subphrenic pericardiectomy with or without cisterna chyli ablation for treatment of idiopathic chylothorax in cats.

OBJECTIVE To compare duration of surgery, recurrence rate, and survival time between cats with idiopathic chylothorax treated with thoracic duct ligation (TDL) plus subphrenic pericardiectomy (SPC) and those treated with TDL, SPC, and cisterna chyli ablation (CCA). DESIGN Retrospective case series with nested cohort study. ANIMALS 22 client-owned cats surgically treated for idiopathic chylothorax from 2009 through 2014. PROCEDURES Patient and surgery data were collected from the medical records. Recurrence of chylothorax and survival time were assessed by medical record review and client interview. Comparisons were made between cats treated with TDL plus SPC (TDL-SPC group) and those treated with TDL, SPC, and CCA (TDL-SPC-CCA group). RESULTS 15 cats were treated with TDL plus SPC, and 7 were treated with TDL, SPC, and CCA. Median duration of surgery was significantly briefer for the TDL-SPC group (80 minutes; range, 55 to 175 minutes) than for the TDL-SPC-CCA group (125 minutes; range, 105 to 205 minutes). Five cats (2 in the TDL-SPC group and 3 in the TDL-SPC-CCA group) had persistent pleural effusion 4 weeks after surgery. Chylothorax recurred in 2 cats (1/group). Median survival time in the TDL-SPC group was 774 days (range, 3 to 2,844 days) and in the TDL-SPC-CCA group was 380 days (range, 11 to 815 days); these values did not differ significantly. CONCLUSIONS AND CLINICAL RELEVANCE Addition of CCA to the surgical treatment approach for cats with idiopathic chylothorax was associated with a significantly longer duration of surgery with no better outcome than achieved with TDL plus SPC alone.

Frequency of Dehiscence in Hand-Sutured and Stapled Intestinal Anastomoses in Dogs.

OBJECTIVE: To determine the frequency of dehiscence of hand-sutured and stapled intestinal anastomoses in the dog and compare the surgery duration for the methods of anastomosis. STUDY DESIGN: Historical cohort study. SAMPLE POPULATION: Two hundred fourteen client-owned dogs undergoing hand-sutured (n = 142) or stapled (n = 72) intestinal anastomoses. METHODS: Medical records from 5 referral institutions were searched for dogs undergoing intestinal resection and anastomosis between March 2006 and February 2014. Demographic data, presence of septic peritonitis before surgery, surgical technique (hand-sutured or stapled), surgery duration, surgeon (resident versus faculty member), indication for surgical intervention, anatomic location of resection and anastomosis, and if dehiscence was noted postoperatively were retrieved. Estimated frequencies were summarized and presented as proportions and 95% confidence intervals (CI) and continuous outcomes as mean (95% CI). Comparisons were made across methods of anastomosis. RESULTS: Overall, 29/205 dogs (0.14, 95% CI 0.10-00.19) had dehiscence, including 21/134 dogs (0.16, 0.11-0.23) undergoing hand-sutured anastomosis and 8/71 dogs (0.11, 0.06-0.21) undergoing stapled anastomosis. There was no significant difference in the frequency of dehiscence across anastomosis methods (χ(2), P = .389). The mean (95% CI) surgery duration of 140 minutes (132-147) for hand- sutured anastomoses and 108 minutes (99-119) for stapled anastomoses was significantly different (t-test, P < .001). CONCLUSION: No significant difference in frequency of dehiscence was noted between hand- sutured and stapled anastomoses in dogs but surgery duration is significantly reduced by the use of staples for intestinal closure.

Outcome of permanent tracheostomy for treatment of upper airway obstruction in cats: 21 cases (1990-2007).

OBJECTIVE: To determine clinical outcome of permanent tracheostomy in cats with upper airway obstruction. DESIGN: Retrospective case series. ANIMALS: 21 cats. PROCEDURES: Medical records were reviewed for information on history, signalment, clinical signs, results of preoperative clinicopathologic testing, cause of upper airway obstruction, surgical procedure, postoperative complications, and outcome. RESULTS: Causes of upper airway obstruction included neoplasia (squamous cell carcinoma [n = 6] or malignant lymphoma [2]), inflammatory laryngeal disease (5), laryngeal paralysis (4), trauma (3), and a laryngeal mass of unknown cause (1). Fourteen cats had dyspnea in the immediate postoperative period; dyspnea most often resulted from mucous plugs at the stoma or elsewhere in the respiratory tract. Eleven cats died, including 6 cats that died while hospitalized after surgery and 5 cats that died after discharge; 7 cats were euthanatized, most often because of progression of neoplasia; and 2 were still alive at the time of the study. The remaining cat was lost to follow-up after discharge from the hospital. Overall, median survival time for the 20 cats for which information was available was 20.5 days (range, 1 day to 5 years). Cats that underwent permanent tracheostomy because of inflammatory laryngeal disease were 6.61 times as likely to die as cats that underwent permanent tracheostomy for any other reason. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that permanent tracheostomy was an uncommon procedure in cats with upper airway obstruction that was associated with high complication and mortality rates.

Comparison of the effects of the CO2 surgical laser and conventional surgical techniques on healing and wound tensile strength of skin flaps in the dog.

OBJECTIVE: To determine if CO(2) laser was superior to conventional surgical techniques (CST) for creation of skin flaps in dogs as determined by hemostasis, wound healing, and wound tensile strength. STUDY DESIGN: In-vivo model ANIMALS: Six large, mixed-breed dogs. METHODS: On each dog's trunk, 3 pairs of identical, dorsally based, pedicled skin flaps were created and sutured back into position. Based on a Latin Square design, flaps on one side were created with a CO(2) laser and on the other side by CST. Intraoperative hemorrhage was measured by weighing sponges used to absorb blood. On days 7, 10, and 14, specimens from the flap-skin junction and the central portion of each pair of flaps were collected. Specimens were subjected to tensile strength testing and histologic examination to evaluate wound healing. RESULTS: Mean (+/- standard error of mean [SEM]) hemorrhage was significantly less (P =.02) with CO(2) laser (4.70 +/- 1.37 g) than CST (10.82 +/- 1.37 g). Wound tensile strength (N/m(2)) after CST (0.49 +/- 0.049) was significantly greater (P =.01) than with CO(2) laser (0.17 +/- 0.049). Laser incisions had partial necrosis of the wound edges and a more extensive inflammatory response; however, healing of the wound beds were similar regardless of technique. CONCLUSIONS: The CO(2) laser provided better intraoperative hemostasis than CST. However, overall healing and increase in tensile strength of the skin-flap junction of the flaps created by the laser may be delayed during the first few weeks of wound healing. CLINICAL RELEVANCE: Skin flaps used to repair large skin defects in dogs can be created and elevated with a CO(2) laser. In areas of increased skin mobility or tension, skin flaps created with CO(2) laser may be more susceptible to complications such as dehiscence, and care should be taken to minimize these complications.

Use of carbon dioxide laser for onychectomy in cats.

OBJECTIVE: To compare postoperative signs of discomfort and complications associated with use of CO2 laser for onychectomy with those of the scalpel technique in cats. DESIGN: Prospective, randomized, masked clinical trial. ANIMALS: 20 client-owned cats. PROCEDURE: Forelimb feet (right, left) were randomly assigned to laser and scalpel treatment groups. Signs of discomfort (lameness and signs of pain) and complications (hemorrhage, swelling, and discharge) were assessed on days 0, 1, and 7. Surgeries were performed by 1 experienced surgeon. Evaluations were performed by 2 individuals without knowledge of treatment group. Signs of discomfort and complications were scored on scales of 0 to 8 and 0 to 9, respectively. RESULTS: Onychectomy did not result in high discomfort or complication scores 1 day after surgery, regardless of technique used, although the laser-treated group had significantly lower scores for signs of discomfort and complications. Seven days after surgery, significant differences were not detected between groups for signs of discomfort or complications. CONCLUSIONS AND CLINICAL RELEVANCE: The CO2 laser can be an excellent tool for onychectomy in cats, with excellent hemostasis and minimal postoperative discomfort and complications. Differences in discomfort and complications between groups treated via scalpel versus CO2 laser were not clinically relevant and were only observed 1 day after surgery.