Incidence of Sterile Hemorrhagic Cystitis in Dogs Treated with Cyclophosphamide and Low-Dose Furosemide.

Cyclophosphamide is a commonly used chemotherapy in the treatment of lymphoma. It can cause sterile hemorrhagic cystitis (SHC), and furosemide is used to decrease the incidence of SHC. The aim of this study is to evaluate the incidence of SHC in dogs treated with a bolus maximum tolerated dose of oral cyclophosphamide and oral furosemide at a dose of 1 mg/kg. Medical records were reviewed to determine the incidence of SHC, dose and number of oral cyclophosphamide treatments, and the dose of furosemide. Other side effects from cyclophosphamide were also recorded. Eighty-one client-owned dogs that received a single oral maximum tolerated dose of cyclophosphamide concurrent with oral furosemide as part of a chemotherapy protocol for lymphoma were included in the study. A total of 252 doses of cyclophosphamide were administered to 81 dogs. The median dose of cyclophosphamide was 239.3 mg/m2. The median dose of furosemide was 1.08 mg/kg. SHC was suspected in 2 dogs (2.46%). Concurrent use of furosemide at a dose of 1 mg/kg with cyclophosphamide yields a similar incidence of SHC than using a higher dose of furosemide as previously reported.

Computed tomography features of presumed normal mandibular and medial retropharyngeal lymph nodes in dogs.

Computed tomographic (CT) features of lymph nodes are used for diagnosis, staging, and response evaluation in veterinary patients. The objectives of this study were to describe maximum short- and long-axis transverse diameters (SATD and LATD, respectively), volume, and attenuation of presumed normal canine mandibular lymph nodes (MLNs) and medial retropharyngeal lymph nodes (MRLNs), to investigate the effect of variables on these features, and to describe inter-observer reliability of transverse diameter and attenuation measurement. Computed tomography studies of 161 dogs were retrospectively reviewed. Median values for SATD were 5.2 and 5.4 mm, median values for volume were 0.26 and 0.54 cm3, and median values for attenuation were 32.3 and 31.8 Hounsfield units (HU) for MLN and MRLN, respectively. Median LATD was 11 mm for MLNs. Height of the first cervical vertebra (HCV1) and weight were positively associated with transverse diameters of both MLNs and MRLNs (P < 0.001). Grade of dental disease was negatively associated with transverse diameters of both MLNs (P = 0.001) and MRLNs (P < 0.03). The intraclass correlation coefficient (ICC) was 0.94 [95% confidence interval (CI): 0.94 to 0.95] for transverse diameter measurement. This study provides descriptive data on the CT characteristics of presumed normal MLNs and MRLNs in dogs and describes a highly reliable method of measuring transverse diameter.

Les caractéristiques tomodensitométriques (CT) des ganglions lymphatiques sont utilisées pour le diagnostic, la stadification et l'évaluation de la réponse chez les patients vétérinaires. Les objectifs de cette étude étaient de décrire les diamètres transversaux maximaux à axe court et long (SATD et LATD, respectivement), le volume et l'atténuation des ganglions lymphatiques mandibulaires canins (MLN) et des ganglions lymphatiques rétropharyngés médians (MRLN) présumés normaux, afin d'étudier l'effet de variables sur ces caractéristiques, et pour décrire la fiabilité inter-observateur de la mesure du diamètre transversal et de l'atténuation. Des études de tomodensitométrie de 161 chiens ont été examinées rétrospectivement. Les valeurs médianes pour la SATD étaient de 5,2 et 5,4 mm, les valeurs médianes pour le volume étaient de 0,26 et 0,54 cm3, et les valeurs médianes pour l'atténuation étaient de 32,3 et 31,8 unités Hounsfield (HU) pour MLN et MRLN, respectivement. Le LATD médian était de 11 mm pour les MLN. La hauteur de la première vertèbre cervicale (VHC1) et le poids étaient positivement associés aux diamètres transversaux des MLN et des MRLN (P < 0,001). Le grade de maladie dentaire était négativement associé aux diamètres transversaux des MLN (P = 0,001) et des MRLN (P < 0,03). Le coefficient de corrélation intraclasse (ICC) était de 0,94 [intervalle de confiance (IC) à 95 % : 0,94 à 0,95] pour la mesure du diamètre transversal. Cette étude fournit des données descriptives sur les caractéristiques CT des MLN et MRLN présumés normaux chez le chien et décrit une méthode très fiable de mesure du diamètre transversal.(Traduit par Docteur Serge Messier).

Inter- and intraobserver agreement for CT measurement of mandibular and medial retropharyngeal lymph nodes is excellent in dogs with histologically confirmed oral melanoma.

Mandibular and medial retropharyngeal lymph nodes are routinely evaluated with CT when staging dogs with oral melanomas. While size alone is considered inadequate for detecting nodal metastasis, it is critical in evaluating treatment response, as clinical decisions are based on changes in size. It is common for different radiologists to measure the size of pre- and posttreatment lymph nodes in the same patient. The objective of this retrospective, observer agreement study was to evaluate the inter- and intraobserver agreement in measuring canine mandibular and medial retropharyngeal lymph nodes by a diverse population of veterinary radiologists and trainees. Fourteen dogs with documented oral melanoma and head CT studies identified from records of a single institution were included in this study. North American veterinary radiologists and trainees were recruited to measure the mandibular and medial retropharyngeal lymph nodes; in triplicate. Prior to performing the study measurements, participants completed a training tool demonstrating the lymph node measurements. Overall, interobserver intraclass correlation coefficient (ICC) was 0.961 (95% confidence interval [CI]: 0.946, 0.972) and intraobserver ICC was 0.977 (95% CI: 0.968, 0.983), indicating excellent agreement (ICC > 0.9 considered excellent). Similar findings were noted following sub-analysis for most variables (experience, size, laterality, axis of measurement). These results suggest that follow-up measurement of the long and short axis of the mandibular lymph nodes and short axis of the medial retropharyngeal lymph nodes in the transverse plane, performed by different veterinary radiologists using the same method of measure, should have minimal impact on clinical decision making.

Stereotactic body radiation therapy for treatment of soft tissue sarcomas in 35 dogs.

OBJECTIVE: To describe response rate, tumor progression, patient survival times, prognostic factors associated with tumor progression and patient survival times, and radiation toxicoses (acute and latent) in dogs treated with curative-intent stereotactic body radiation therapy (SBRT) for soft tissue sarcomas (STS). ANIMALS: 35 client-owned dogs with STS treated with curative-intent SBRT between October 2011 and May 2017. PROCEDURES: Medical records were reviewed to identify dogs that underwent SBRT. Dogs with oral tumors, hemangiosarcoma, or histiocytic sarcoma were excluded. Data collected included patient-, STS-, and SBRT-related information, including follow-up information pertaining to tumor progression and patient survival time for ≥ 6 months, unless tumor progression or patient death occurred sooner. RESULTS: Objective measurements allowing for evaluation of tumor response were available for 28 dogs, of which 13 (46%) had either a partial (10/28 [36%]) or complete (3/28 [11%]) response. Twenty-four dogs died, and the medians for progression-free survival time, time to progression of disease, overall survival time, and disease-specific survival time were 521, 705, 713, and 1,149 days, respectively. Low histologic grade and extremity locations of STSs were positive prognostic factors for patient survival times. Acute adverse effects were limited to skin, and 1 dog underwent limb amputation because of a nonhealing wound. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that SBRT for STS was well tolerated in most dogs and provided local tumor control. Additional studies are needed to determine the best SBRT protocol for treatment of STSs in dogs.

Use of three-dimensional conformal radiation therapy for treatment of a heart base chemodectoma in a dog.

CASE DESCRIPTION: A 9-year-old spayed female mixed-breed dog was evaluated because of a progressively worsening, nonproductive cough and gagging of 1 year's duration. CLINICAL FINDINGS: Physical examination results were unremarkable. A cranial mediastinal mass was identified at the heart base with 3-view thoracic radiography. A CT scan of the thorax revealed an invasive mass surrounding major vessels at the heart base that was not considered surgically resectable. Thoracoscopic biopsy specimens of the cranial mediastinal mass were obtained, and histologic evaluation revealed that the tumor was a chemodectoma. TREATMENT AND OUTCOME: On the basis of results of the CT scan, a 3-D conformal radiation therapy plan was generated with computer treatment-planning software. The patient was treated with external beam radiation therapy; a 6-MV linear accelerator was used to deliver a prescribed dose of 57.5 Gy in twenty-three 2.5-Gy fractions. The cough improved following radiation therapy. Prior to treatment, the tumor volume was calculated to be 126.69 cm(3). Twenty-five months following radiation therapy, a follow-up CT scan was performed and there was a >50% reduction in tumor volume at that time. Disease progression causing pericardial, pleural, and peritoneal effusion and syncopal episodes occurred 32 months following radiation therapy, which were treated with pericardectomy and additional radiation therapy. The dog was still alive and doing well 42 months following initial radiation treatment. CLINICAL RELEVANCE: Conformal radiation therapy provided an additional treatment option for a nonresectable heart base chemodectoma in the dog of this report; conformal radiation therapy was reasonably tolerable and safe.

Treatment-related toxicities in tumor-bearing cats treated with temozolomide alone or in combination with doxorubicin: a pilot assessment.

A retrospective study assessing treatment-related toxicities in tumor-bearing cats treated with temozolomide (TMZ) alone or in combination with doxorubicin was conducted. TMZ was administered orally once a day for 5 days every 3 weeks at a dose of 20 mg/cat. Tumor response was evaluated with standard World Health Organization criteria and toxicity was monitored using veterinary co-operative oncology group-common terminology criteria for adverse events (VCOG--CTCAE) criteria. Ten tumor-bearing cats with various types of malignancies were treated with TMZ-based chemotherapy. Eight cats were evaluable for response. Two cats achieved a complete response, one achieved stable disease and five achieved a partial response. Four grade III and one grade IV hematological toxicities, and one grade IV gastrointestinal toxicity were observed. Four cats were euthanased as a result of apparent toxicity. One cat was euthanased as a result of severe and prolonged myelosuppression with fever. Three were euthanased for grade III pleural and pericardial effusions. Effusion was seen in cats treated with higher cumulative dose of TMZ (P = 0.0046). Planned additional case accrual was discontinued because of unacceptable levels of toxicity despite evidence of efficacy in some of the cats. Additional investigation is needed to elucidate this unexpected apparent cumulative toxicity.