Case Study

Lymphoma diagnosed by trucut biopsy of mediastinal lymph node in a 7-year-old MN Boxer dog

A 7-year-old MN Boxer with history of hypothyroidism (on Soloxine) was presented for PU/PD and decreased appetite. Physical examination of the dog was non-remarkable. Abnormalities on blood chemistry were elevated ALP and ALT activity, marked hypercalcemia, and hyperglobulinemia. An ACTH stimulation test was within normal range.

Sonographic Differential Diagnosis

Cranial mediastinal parenchymal mass: lymphoma or similar neoplasia likely, thymoma minimally possible.

Image Interpretation

A large, dramatically hypoechoic to anechoic cranial mediastinal mass is noted. This is likely of lymph node origin given that no trapped air is present nor is there peripheral scalloping of a normal lung/alveolar air interface. The linear focus in video 2 represents core biopsy trajectory into the mass.

DX

Lymphoma, enlarged mediastinal lymph nodes

Outcome

Biopsy revealed lymphoma.

Clinical Differential Diagnosis

Neoplasia (lymphoma/anal sac carcinoma/soft tissue sarcomas), granulomatous disease (idiopathic/fungal), hypervitaminous D, renal disease, hyperparathyroidism