Surgical approach and presence of preoperative pleural effusion impact thoracostomy tube usage in dogs and cats following thoracic surgery for suspected neoplasia.

OBJECTIVE: To assess factors associated with increased pleural fluid and air evacuation, longer duration of thoracostomy tube usage, and longer hospitalization in dogs and cats following surgery for thoracic neoplasms. ANIMALS: 62 dogs and 10 cats. METHODS: Medical records were reviewed for dogs and cats undergoing thoracic surgeries between August 1, 2019, and June 30, 2023, for resection of suspected neoplasia in which a thoracostomy tube was placed. Data collected included patient signalment, type of procedure performed, histologic diagnosis of the primary mass removed, volume of fluid and air evacuated from the thoracostomy tube, and time in hospital. RESULTS: Median sternotomy was associated with increased total fluid evacuation (median, 12.1 mL/kg; IQR, 15.4 mL/kg; P = .012), whereas rib resection was associated with increased total air evacuation (median, 2.1 mL/kg; IQR, 13.6 mL/kg; P = .06). The presence of preoperative pleural effusion was associated with higher total fluid evacuation (20.6 mL/kg; IQR, 32.1 mL/kg; P = .009), longer duration with a thoracostomy tube in place (42.5 hours; IQR, 41.9 hours; P = .027), and longer hospitalization period (61 hours; IQR, 52.8 hours; P = .025). Cats had a thoracostomy tube in place for a longer time compared to dogs (median, 42.6 hours; IQR, 23.5 hours; P = .043). CLINICAL RELEVANCE: Animals undergoing median sternotomy and rib resection may be expected to have higher fluid and air volumes, respectively, evacuated postoperatively. This often leads to an increased duration of thoracostomy tube usage and a longer period of hospitalization.

Unilateral nephrectomy in dogs is associated with a high rate of intraoperative and postoperative complications.

OBJECTIVE: To determine the incidence of complications in the intraoperative and postoperative period for dogs undergoing nephrectomy for renal disease. ANIMALS: 69 dogs. METHODS: Medical records of dogs undergoing nephrectomies for renal disease were reviewed for signalment, date of surgery, results of blood analyses, and intra- and postoperative complications. Long-term follow-up was obtained via client telephone interview or referring veterinarian medical records. A Fisher exact test was used to assess the relationship between postoperative acute kidney injury and NSAID administration with long-term development of chronic kidney disease. RESULTS: Complications occurred in 44.9% and 42.6% of dogs in the intraoperative and postoperative periods, respectively. Most of these were lower-grade complications, though a total of 7 dogs died during the postoperative period. An acute kidney injury was diagnosed in 12 dogs postoperatively, with 2 dogs euthanized due to the severity of the injury. Long-term follow-up was available for 53 dogs, with 24 (45.3%) dogs developing chronic kidney disease. Postoperative acute kidney injury (P = .385) and NSAID administration (P = .519) were not statistically associated with the development of chronic kidney disease in this population. CLINICAL RELEVANCE: Unilateral nephrectomy is associated with high intraoperative and postoperative complication rates in dogs. Chronic kidney disease was diagnosed in almost 50% of the population with available long-term follow-up.

Outcome in dogs with invasive adrenal gland tumors that did not pursue adrenalectomy.

OBJECTIVE: To report the survival times in dogs diagnosed with adrenal tumors with vascular or soft tissue invasion that did not undergo adrenalectomy. ANIMALS: Retrospective case series of 32 client-owned dogs. METHODS: The medical records of a referral veterinary hospital were reviewed to identify dogs that were diagnosed with an invasive adrenal mass and did not undergo adrenalectomy between January 2013 and December 2022. Data collected included signalment, examination findings, and diagnostic results from the initial presentation. Descriptive statistics were calculated to summarize dog signalment information, and Kaplan-Meier survival analysis was performed for calculation of median survival time. RESULTS: Most dogs (n = 28) had vascular invasion, primarily into the caudal vena cava. Surgery was offered but not pursued due to perceived risk of sudden death (n = 5), risk of hemorrhage (4), or concurrent diagnosis of disseminated intravascular coagulation (1). Only 1 dog pursued stereotactic body radiation therapy, and 1 was prescribed toceranib phosphate (Palladia). Of these 32 dogs, 30 (93.8%) died or were euthanized and 2 (6.2%) dogs survived. The median follow-up time was 49 days (range, 0 to 1,910 days). The median survival time was 50 days (95% CI, 4 to 194 days). The most common cause of death or euthanasia was hemoabdomen (n = 8). CLINICAL RELEVANCE: Nonsurgical management of invasive adrenal tumors was associated with short survival times in this case series.

Hypercoagulability based on thromboelastography is common in dogs undergoing adrenalectomy.

OBJECTIVE: Thromboelastography (TEG) is a whole blood assay that yields global assessment of hemostasis, as it evaluates clot time, strength, and kinematics of clot formation and lysis. The main objective was to describe preoperative TEG findings in dogs that had an adrenalectomy performed and, secondarily, to describe TEG findings in the dogs with or without hyperadrenocorticism (HAC). ANIMALS: 30 dogs that had preoperative TEG and adrenalectomy performed. METHODS: Medical records between 2018 and 2022 were reviewed. Signalment, diagnostic data, and perioperative treatment were abstracted. RESULTS: 53% (16/30) of the dogs were hypercoagulable, and none were hypocoagulable. Based on histopathology, 6 of 9 dogs with adenocarcinoma were hypercoagulable, 4 of 8 with pheochromocytoma were hypercoagulable, and 6 of 10 with adenoma were hypercoagulable. None of the 3 dogs with other histopathologic diagnoses or combinations of diagnoses (adrenocortical hyperplasia, poorly differentiated sarcoma, and both adrenocortical adenocarcinoma and pheochromocytoma) were hypercoagulable. Of the 14 dogs tested preoperatively for HAC, 4 of 8 HAC dogs were hypercoagulable and 2 of 6 non-HAC dogs were hypercoagulable. CLINICAL RELEVANCE: The present report describes for the first time TEG findings for dogs undergoing adrenalectomy and suggests that the majority of dogs with adrenal neoplasia are hypercoagulable based on TEG results.

Prospective assessment of canine thyroid cancer-part I: nodal metastatic rate and impact of nodal immunohistochemistry in 70 dogs.

OBJECTIVE: To determine the rate of nodal metastasis in dogs with thyroid cancer and evaluate whether immunohistochemistry (IHC) identifies additional metastases beyond evaluation with H&E. ANIMALS: 70 prospectively enrolled client-owned dogs with thyroid cancer managed with thyroidectomy. METHODS: Dogs underwent thyroidectomy with concurrent elective bilateral medial retropharyngeal (MRP) ± deep cervical lymphadenectomy. Thyroid tumors and associated lymph nodes were reviewed by a single board-certified pathologist. Immunohistochemistry was used for all primary tumors (thyroid transcription factor-1 and calcitonin) to support a diagnosis of follicular or medullary carcinoma. Lymph nodes without evidence of metastasis after H&E review were labeled with the antibody associated with the wider uptake in the primary tumor. RESULTS: 77 thyroid cancers were resected from the 70 dogs enrolled, including 61 (79.2%) follicular, 8 (10.7%) medullary, and 7 (9.3%) mixed follicular/medullary carcinomas, with 1 (1.3%) carcinosarcoma. Twelve dogs had evidence of nodal metastasis following H&E review. Occult micrometastasis was identified in 1 dog following nodal IHC, resulting in documented metastasis in 13 of 70 (18.6%) dogs. Metastasis was more common with medullary (5/8) and follicular/medullary carcinoma (3/7) than follicular carcinoma (5/61). All MRP metastases were ipsilateral (7/77 [9.1%]), without contralateral MRP metastases (0/62). Fourteen of 41 (34.1%) deep cervical lymph nodes were metastatic. CLINICAL RELEVANCE: Nodal metastasis was uncommon for follicular carcinoma but was seen in > 50% of dogs with thyroid cancer involving a medullary component. Routine nodal IHC appears to be low yield for thyroid carcinoma. Extirpation of ipsilateral MRP and identifiable deep cervical lymph nodes is recommended with thyroidectomy until detailed preoperative risk stratification becomes available.

Treatment of retroperitoneal sarcoma results in improved outcomes.

OBJECTIVE: To report the clinical characteristics, treatments, and outcomes in a cohort of dogs with histologically confirmed retroperitoneal sarcoma (RPS) and to identify potential variables of prognostic significance. ANIMALS: 46 client-owned dogs from 10 clinics with histopathologic diagnosis of a sarcoma originating from the retroperitoneal space. METHODS: Medical records were retrospectively reviewed to obtain information regarding clinical characteristics, treatments, and outcomes. Recorded variables were analyzed to report descriptive data for all cases and overall survival time. Multivariate analysis was utilized to evaluate prognostic factors for overall survival. RESULTS: Hemangiosarcoma was the most common histologic subtype diagnosed (76.1%). Cytoreductive and curative intent surgical excision of the RPS was attempted in 12 and 22 dogs, respectively; 12 dogs underwent no surgery or had an exploratory laparotomy with incisional biopsy only. Nineteen dogs received adjuvant chemotherapy, either injectable or metronomic, and 1 dog received adjuvant radiation therapy. Fourteen of the 34 (41.2%) surgically treated dogs developed evidence of local recurrence, but there was no difference in local recurrence when comparing dogs categorized as curative intent versus cytoreductive surgery. The median overall survival time was 238 days. On multivariable analysis, treatment approach was associated with survival with surgical excision (vs palliative treatment) and adjuvant chemotherapy following surgery being protective against death. A diagnosis of hemangiosarcoma was associated with a greater hazard of death. CLINICAL RELEVANCE: This study demonstrates a substantially greater survival time than previously published and suggests a survival benefit from surgical excision and adjuvant chemotherapy.