Hypoglycemia associated with disseminated metastatic tonsillar squamous cell carcinoma producing insulin-like growth factor-I in a Pomeranian dog.

A 13-year-old spayed female Pomeranian dog was presented for persistent, severe hypoglycemia (37 mg/dL; reference interval [RI] 75-128 mg/dL). Progressive nonregenerative anemia (hematocrit 23.3%-15.9%; RI 37.0%-55.0%) and severe thrombocytopenia (36 000/µL; RI 200-500 000/µL) were also noted. The serum insulin concentration was low (0.24 ng/mL; RI 0.302-1.277 ng/mL). Computed tomography revealed multiple splenic nodules (1-6 mm in diameter) and several hepatic nodules (7.6, 12 mm in diameter). Ultrasound-guided fine-needle aspiration of the splenic and hepatic nodules revealed low numbers of epithelial cells with mild cellular atypia, suggestive of a metastatic epithelial tumor, but the primary site was unknown at that time. On careful oral examination under general anesthesia, an enlarged right tonsil was noted grossly, and histopathologic examination of the tonsil diagnosed squamous cell carcinoma. Bone marrow aspirates and biopsies of the splenic and hepatic nodules were performed; all samples were diagnosed as metastatic carcinoma on histopathologic examination. No nodules were present in the pancreas, despite careful palpation during exploratory laparotomy. On immunohistochemistry, the neoplastic cells were positive for cytokeratin AE1/3 and insulin-like growth factor (IGF)-I but were negative for chromogranin A, PGP9.5, insulin, and inconclusive for IGF-II. This is the first report of a primary IGF-I-producing squamous cell carcinoma in the tonsil of a dog with metastases to bone marrow, liver, and spleen, resulting in hypoglycemia.

Triple-phase helical computed tomography of an arterio-hepatic venous shunt in a hepatic tumor in a dog.

A 10-year-old French bulldog presented with an abdominal tumor. Triple-phase helical computed tomography was performed, revealing a hepatic tumor, an enlarged hepatic lymph node, and no masses in other organs. The hepatic tumor demonstrated marked enhancement, similar to that of the aorta in the arterial phase. The tumor had rich vascularization and a hepatic arterio-venous shunt formed between the hepatic artery and middle hepatic vein. The hepatic tumor was surgically removed and histological diagnosis revealed a hepatic carcinoid tumor. During surgery, rapid massive arterial hemorrhage occurred from the site of the incision. The animal died without improvement post-surgery. In the case of an arterio-venous shunt in a hepatic tumor, it is important to be careful to avoid perioperative bleeding.

IMAGING DIAGNOSIS-ECTOPIC SPLEEN MIMICKING HEPATIC TUMOR WITH INTRA-ABDOMINAL METASTASES INVESTIGATED VIA TRIPLE-PHASE HELICAL COMPUTED TOMOGRAPHY IN A DOG.

A 10-year-old castrated male miniature dachshund was presented with an abdominal mass. The dog had a history of splenectomy. Triple-phase helical computed tomography was utilized, revealing a hepatic mass and multiple intra-abdominal solid masses. In triple-phase helical computed tomography the images, hepatic mass and two of four intra-abdominal masses were heterogenous in all phases. Therefore, we diagnosed a malignant hepatic tumor and presumed intra-abdominal metastases. The masses were surgically removed and were histologically composed of normal spleen tissues, findings which were consistent with ectopic spleen.