Analysis of Dual-Energy Computed Tomography Imaging for the Evaluation of Lymph Node Metastasis in Canine Anal Sac Gland Adenocarcinoma: A Case Report.

A 9-year-old neutered male miniature schnauzer was referred to our facility with polyuria, polydipsia, persistent hypercalcemia, hypophosphatemia, and elevated parathyroid hormone-related protein. Dual-energy computed tomography (DECT) imaging revealed a mass in the left anal gland (LAG) and enlargement of the left medial iliac lymph node (LML) and the left internal iliac lymph node (LIL). The mass was surgically removed, and the histopathological diagnosis was anal sac gland adenocarcinoma, with metastasis to the LML and LIL. The pathological findings were concordant with those obtained from our evaluation of the spectral Hounsfield unit curve and iodine concentration DECT imaging. DECT analysis may be useful for identifying metastatic lymph nodes.