Retrospective evaluation of the diagnostic utility of computed tomography in dogs with nontraumatic hemoperitoneum: 26 cases (2015-2020).

OBJECTIVE: To describe the appearance of lesions noted on abdominal computed tomography (CT) in dogs with spontaneous hemoperitoneum and determine the utility in using CT to differentiate benign from malignant lesions. DESIGN: Retrospective case series. SETTING: Single-center, university veterinary teaching emergency service. ANIMALS: Twenty-six dogs presented between 2015 and 2020 with spontaneous hemoperitoneum confirmed via abdominocentesis with pre- and postcontrast abdominal CT performed prior to surgery or euthanasia. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: On histopathological diagnosis, 20 of 26 lesions were found to be malignant, and 6 of 26 were benign. Two radiologists reviewed the CTs. Radiologist 1 correctly identified 5 of 6 (83.3%) benign cases and 18 of 20 (90%) malignant cases. Radiologist 2 correctly identified 2 of 6 (33.3%) benign lesions and 18 of 20 (90%) malignant cases. Of the 10 imaging descriptors evaluated, none were significantly associated with the histological diagnosis. CONCLUSIONS: Results from the current study suggest that abdominal CT imaging of spontaneous hemoperitoneum cases is not a reliable indicator of malignancy versus benignancy. As such, prognosis should not be defined using this modality alone prior to emergency surgery and instead should be concluded based on the clinical course of the patient and histopathological findings of the resected tissues after surgery.

Cavitary pulmonary lesion wall thickness, presence of additional nodules, and intralesional contrast enhancement are associated with malignancy in dogs and cats.

OBJECTIVE: To investigate the CT features of cavitary pulmonary lesions and determine their utility to differentiate malignant from benign lesions. ANIMALS: This retrospective study included cases from 5 veterinary medical centers between January 1 2010, and December 31, 2020. Inclusion criteria included having a gas-filled cavitary pulmonary lesion on thoracic CT and definitive diagnosis by either cytology or histopathology. Forty-two animals (27 dogs and 15 cats) were included in this study. PROCEDURES: Medical records systems/imaging databases were searched, and cases meeting inclusion criteria were selected. The CT studies were interpreted by a third-year radiology resident, and findings were reviewed by a board-certified veterinary radiologist. RESULTS: 7 of the 13 lesion characteristics investigated were not statistically associated with the final diagnosis of the lesion, whereas 6 were statistically associated. Those that were associated included the presence of intralesional contrast enhancement, type of intralesional contrast enhancement (heterogenous and homogenous analyzed separately), presence of additional nodules, wall thickness of the lesion at its thickest point, and wall thickness at the thinnest point. CLINICAL RELEVANCE: Results from the present study showed that thoracic CT imaging of cavitary pulmonary lesions can be used to further refine the list of differential diagnoses. Based on this data set, in lesions that have heterogenous contrast enhancement, additional pulmonary nodules, and wall thickness > 40 mm at their thickest point, it would be reasonable to consider malignant neoplastic disease higher on the list of differentials than other causes.