Case Study

Parathyroid mass in a 13 year old MN Siberian Husky dog

A 13-year-old NM Husky was presented for evaluation of hyperparathyroidism with a serum calcium >16.

DX

Parathyroid enlargement

Sonographic Differential Diagnosis

Left parathyroid adenoma or possible adenocarcinoma with concurrent parathyroid nodule. The presumed adenoma is the internal parathyroid whereas the slightly enlarged nodule is the cranial parathyroid.

Image Interpretation

Left thyroid lobe revealed a 1.22 x 0.71 cm nodule with separate hypoechoic nodule cranial to it at 0.3 cm. The thyroid lobe itself measured 3.12 x 0.75 cm. Right thyroid lobe was unremarkable, uniform with hyperechoic nodule consistent with fatty deposit 0.39 cm; right parathyroids not visible. Minor parenchymal remodeling noted. The left internal parathyroid appears to be the enlarged lesion with loss of parenchymal detail and irregular contour most consistent with adenoma, mild potential for parathyroid adenocarcinoma. Cranial to it the 0.29 cm hypoechoic nodule is uniform. No evidence of regional metastasis is noted in the image set provided.

Outcome

Recommendation is removal of both the internal and cranial parathyroid lesions on the left lobe. Full thyroid panel is recommended in this patient if T4 is subnormal.