Outcome of intensity-modulated radiation therapy-based stereotactic radiation therapy for treatment of canine nasal carcinomas.

Stereotactic radiation therapy (SRT) has emerged as a convenient definitive treatment modality in veterinary medicine, but few studies exist evaluating outcome with treatment for canine nasal tumors, and no studies report the treatment of one single tumor histotype. This retrospective, observational study evaluates toxicity, response, and survival in 17 dogs with nasal carcinomas treated with SRT. Dogs received a median of 3000 centigray in three fractions via 6-MV linear accelerator. Eighty-eight percent of patients (n = 15) demonstrated clinical benefit. Of dogs with repeated CT imaging (n = 10), 60% (n = 6) achieved a partial response and 10% (n = 1) achieved a complete response. Median progression-free survival (PFS) was 359 days. Median survival time (MST) was 563 days. Among dogs evaluable for acute toxicity, 50% (n = 10) developed low grade toxicity (grade 1, n = 4; grade 2, n = 1). No patients developed grade 3 toxicity. 16 dogs (87%) evaluable over the long term developed signs consistent with possible late toxicity. The majority of late toxicities were mild (alopecia, hyperpigmentation, and leukotrichia n = 10; ocular discharge and keratoconjunctivitis sicca n = 5). Thirty-seven percent of patients (n = 6) developed seven possible grade 3 late toxicities (blindness, n = 3; fistula, n = 1; seizures, n = 3), which were difficult to distinguish from progressive disease in most patients. Of the prognostic factors evaluated (demographics, tumor stage, dosimetric data, epistaxis, facial deformity, clinical response, image-based response, nonsteroidal anti-inflammatory drugs, and chemotherapy), only clinical response was a positive prognostic factor on MST (P < .00). No factors were found to be significantly associated with PFS.

Toceranib phosphate in the treatment of canine thyroid carcinoma: 42 cases (2009-2018).

Thyroid carcinoma is the most common endocrine malignancy in dogs. Thyroidectomy and radiation therapy control local disease, yet are not always feasible, and efficacious medical therapies need to be identified. Toceranib phosphate has been reported to provide clinical benefit (CB) in dogs with thyroid carcinoma, while its role in treatment-naïve thyroid tumours has not been well-described. The objective of this study was to describe the use of toceranib in the management of thyroid carcinomas in dogs in both the naïve-disease and prior therapy- settings. A medical record search identified 42 dogs diagnosed with thyroid carcinoma and treated with toceranib, of which 26 and 16 dogs were in settings of naïve-disease and after prior therapy, respectively. Twenty-three (88.4%) and twelve (75%) dogs experienced CB in the naïve and prior therapy settings, respectively. The median [95% confidence interval] progression free interval (PFI) for dogs in the naïve and prior therapy settings were 206 [106,740] and 1015 [92,1015] days, respectively. The median overall survival time (OST) for dogs in the naïve and prior therapy settings were 563 [246,916] and 1082 [289,1894] days, respectively. Overall, the data provided no evidence for differences in overall PFI (P > .20) or OST (P = .15) between settings. However, when asymptomatic at the time of diagnosis, dogs in the naïve setting showed poorer survival prognosis (estimated hazard ratio 17.2 [1.8, 163]) relative to dogs in the prior therapy setting. This study characterizes PFI, OST and CB with minimal AE in dogs with thyroid carcinoma treated with toceranib in both the naïve and prior therapy settings.

RENAL NEOPLASIA FROM A SINGLE POPULATION OF PTEROPODID BATS.

Neoplastic diseases have rarely been reported in the family Pteropodidae, and primary malignant renal neoplasms are generally uncommon across animal species. This case series describes four cases of primary renal neoplasia: three renal cell carcinomas and one nephroblastoma in three species of pteropodid bats, specifically large flying foxes (Pteropus vampyrus, n = 2), straw-colored fruit bat (Eidolon helvum, n = 1), and a little golden-mantled flying fox (Pteropus pumilus, n = 1). Two of the cases were diagnosed antemortem using ultrasonography, computed tomography, and cytology; and one of these bats with a renal cell carcinoma was treated successfully with a unilateral nephrectomy. The remaining two cases were diagnosed at necropsy.

Plasma Bleomycin Concentrations during Electrochemotherapeutic Treatment of Fibropapillomas in Green Turtles Chelonia mydas.

Fibropapillomatosis of sea turtles is traditionally treated with surgical debulking techniques that are often associated with prolonged healing and tumor recurrence. Electrochemotherapy was recently described for green turtles Chelonia mydas and can be an alternative to surgery and even general anesthesia. The objectives of this study were to replicate an electrochemotherapy protocol from a previous report and add plasma bleomycin analysis to the treatment. After bleomycin injection into similarly sized tumors of two green turtles and immediate electroporation at two time points, plasma bleomycin reached detectable concentrations that were considerably lower than those found in human studies. At 3 months posttherapy, no healing complications or recurrences were encountered and only scar tissue remained. This study adds further support that electrochemotherapy with bleomycin has the potential to be used as an effective alternative treatment for this complex disease.

Suspected Carboplatin Extravasation Reactions in Seven Dogs.

Carboplatin is a platinum chemotherapeutic agent commonly used in veterinary oncology that is currently classified as an irritant to local tissues when extravasated. To the authors' knowledge, there are no reports of vesicant injuries associated with carboplatin administration reported in the veterinary literature. In this case series, seven dogs are described to have experienced injuries following a suspected carboplatin extravasation resembling vesicant injuries a median of 7 days after carboplatin administration (range 4-15 days). Wounds healed with a variety of treatments, including medical management and/or surgical debridement, a median of 25.5 days (range 7-49 days) after observation of the suspected extravasation injury. There were no obvious similarities involving carboplatin administration among patients to explain why these reactions occurred. Extravasation injury should be considered a possible local complication associated with carboplatin chemotherapy.

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.

Portal site metastasis after thoracoscopic resection of a cranial mediastinal mass in a dog.

CASE DESCRIPTION: An 11-year-old castrated male Vizsla was evaluated for excision of a cranial mediastinal mass. CLINICAL FINDINGS: The dog had a 1-month history of a cough that had recently increased in frequency. On physical examination, the dog had a grade 2/6 left systolic heart murmur and multiple subcutaneous masses. A soft tissue mass was observed in the cranioventral aspect of the thorax on radiographs. Results of a CT scan revealed a well-defined, 2.8 × 3.2 × 3.9-cm soft tissue mass in the cranial mediastinum. TREATMENT AND OUTCOME: The dog underwent video-assisted thoracoscopic removal of the mediastinal mass and recovered routinely. Histologic examination of excised tissues revealed malignant thymoma. Approximately 6.5 months after surgery, the dog was evaluated because of polyuria, polydipsia, decreased appetite, and vomiting. On physical examination, masses were found in both axillary regions. Results of serum biochemical analysis indicated hypercalcemia. Thoracic ultrasonography revealed pulmonary metastases and a large mass in the right caudoventral region of the thorax. The dog received supportive care and medical treatment for hypercalcemia, but clinical signs recurred. Euthanasia was elected; necropsy and histologic examination revealed thymic carcinoma. CONCLUSIONS AND CLINICAL RELEVANCE: Descriptions of the development of portal site metastasis in canine patients are rare. In this patient, portal site metastasis developed rapidly after thoracoscopic resection of a malignant thymic mass and was associated with hypercalcemia. As use of thoracoscopic procedures increases in veterinary medicine, it will be important to monitor the development of major complications such as those in the patient of this report.