Ciência e Tecnologia Veterinária

Whole Body Computed Tomography for Tumor Staging in Dogs: Review of 16 Cases

Abstract

Bonaparte A*, Dhaliwal RS, Heo J and Murtaugh RJ

Precise tumor staging encompassing the patient’s entire body is essential in cancer management. While more advanced imaging modalities for tumor staging are available, in veterinary medicine, three-view thoracic radiography and abdominal ultrasonography are conventionally performed to screen for pulmonary and abdominal metastases. The objective of this retrospective study was to describe the use of whole-body computed tomography as an alternative in detecting lesions likely to be associated with primary or metastatic neoplasia in dogs. Sixteen dogs that underwent wholebody computed tomography were identified. Fifteen dogs had a histopathologic diagnosis of cancer. One dog had a cytologic diagnosis of thyroid carcinoma. The most common tumor types in this population included mast cell tumors [4; hind limbs (2), sternum (1), prepuce (1)], oral malignant melanomas (2), and spindle cell sarcomas [2; flank (1), cecum (1)]. The most commonly detected thoracic computed tomographic lesions were positional atelectasis (68.8%) and pulmonary nodules (12.5%). The most commonly detected abdominal computed tomographic lesions were splenomegaly (43.8%) and lymphadenomegaly (18.8%). The most commonly detected extra-thoracic/extra-abdominal computed tomographic lesions were cervical and retropharyngeal lymphadenomegaly (31.3%) and thyroid tumors (18.8%). No complications associated with anesthesia or contrast agents given during the procedure were observed and all dogs recovered uneventfully. Median scan time was 37.5 minutes. This study demonstrates that whole-body computed tomography is a safe and time-efficient imaging modality that is effective in identifying a range of pathologic changes important to tumor staging. Further prospective studies are needed to correlate the sensitivity and specificity of whole-body computed tomography with those of a combination of three-view thoracic radiography and abdominal ultrasonography.