Prospective Comparison of Tumor Staging Using Computed Tomography Versus Magnetic Resonance Imaging Findings in Dogs With Nasal Neoplasia: A Pilot Study

Abstract

Identification of nasal neoplasia extension and tumor staging in dogs is most commonly performed using computed tomography (CT), however magnetic resonance imaging (MRI) is routinely used in human medicine. A prospective pilot study enrolling six dogs with nasal neoplasia was performed with CT and MRI studies acquired under the same anesthetic episode. Interobserver comparison and comparison between the two imaging modalities with regard to bidimensional measurements of the nasal tumors, tumor staging using historical schemes, and assignment of an ordinal scale of tumor margin clarity at the tumor-soft tissue interface were performed. The hypotheses included that MRI would have greater tumor measurements, result in higher tumor staging, and more clearly define the tumor soft tissue interface when compared to CT. Evaluation of bone involvement of the nasal cavity and head showed a high level of agreement between CT and MRI. Estimation of tumor volume using bidimensional measurements was higher on MRI imaging in 5/6 dogs, and resulted in a median tumor volume which was 18.4% higher than CT imaging. Disagreement between CT and MRI was noted with meningeal enhancement, in which two dogs were positive for meningeal enhancement on MRI and negative on CT. One of six dogs had a higher tumor stage on MRI compared to CT, while the remaining five agreed. Magnetic resonance imaging resulted in larger bidimensional measurements and tumor volume estimates, along with a higher likelihood of identifying meningeal enhancement when compared to CT imaging. Magnetic resonance imaging may provide integral information for tumor staging, prognosis, and treatment planning.

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

“…One pilot study evaluating MRI in conjunction with CT in dogs with nasal tumors demonstrated improvement in evaluation of margins at the soft tissue‐tumor interface and identification of meningeal enhancement 27 . All patients had a greater than 10% difference (11.2‐32.1%) in calculated tumor volume with combined CT/MRI compared with CT alone 28 . Magnetic resonance imaging may become more valuable in treatment planning and should be considered to improve tumor contouring and patient outcomes.…”

Canine nasal septum deviation can be a normal variation and correlates with increasing skull indices

“…This was consistent with previous studies in cats and dogs and indicated that nasal septum deviation should not be interpreted as a definitive mass effect, even in the presence of a nasal mass, as frequently done in the diagnostic interpretation of other midline structures such as the falx cerebri , mediastinum thoracis , and mediastinum testis . Computed tomography has been established as a gold standard for the diagnosis of canine nasal diseases . Specific CT features, such as turbinate lysis, hyperostosis, soft tissue opacification, contrast enhancement, and mass effect have been established as diagnostic criteria .…”

“…Computed tomography has been established as a gold standard for the diagnosis of canine nasal diseases . Specific CT features, such as turbinate lysis, hyperostosis, soft tissue opacification, contrast enhancement, and mass effect have been established as diagnostic criteria . However, it has also been shown that nasal effusion and secretion, associated with most nasal pathologies, can mask normal turbinate structures, potentially leading to a misdiagnosis of an aggressive nasal mass .…”

Intranasal Osteosarcoma in a Dog—A Case Report

“…Clinical signs associated with intranasal tumors consist of unilateral or bilateral nasal discharge (serous, mucoid, mucopurulent, or epistaxis), or a nonhealing ulcer on the nasal planum and deformation of the nasal planum and nose [9,10]. Less frequently, ocular discharge may be seen due to obstruction of the nasolacrimal duct by the nasal tumor [10]. Dogs with an intranasal mass may also experience discomfort on palpation of the nose and face and have sleeping disturbances ranging from restlessness to interrupted sleep due to obstructed breathing.…”

“…Dogs with an intranasal mass may also experience discomfort on palpation of the nose and face and have sleeping disturbances ranging from restlessness to interrupted sleep due to obstructed breathing. Some dogs with neoplastic obstruction of the air passages do not adapt to open mouth breathing even at rest [10].…”