Histiocytic sarcoma diagnosed by Tru-cut biopsy of thoracic mass in a 7-year-old FS Bernese Mountain Dog: Our Case Of the Month April 2015
Chasing the calcium….Probe here, probe there,… anal gland, iliac, abdomen, cranial mediastinum and parathyroid... find the lesion put a needle in it, or rule out the lesions and declare it idiopathic or toxic… That’s the "Calcium Chase" by the clinical sonographer. Here is a case where we dropped the probe on the cranial mediastinum, found the lesion, biopsied the pathology and got the ugly answer. Boy, we sure wish we had more idiopathic cases. :(
A 7-year-old Bernese Mountain Dog (BMD) was presented for a history of persistent weight loss. The only abnormality on physical examination was a thin body condition. CBC and blood chemistry showed monocytosis, elevated creatinine, hypercalcemia, and mild hyperamylasemia. Survey thoracic radiographs showed a 4cm diameter spherical soft tissue opacity mass arising at the ventral tip of the lung to the right of the cardiac apex within the right middle lung lobe. There was also a 14cm x 6cm x 8cm mass infiltrating the ventral portion of the caudal subsegment of the left cranial lung lobe. No pleural effusion was seen.
Clinical Differential Diagnosis
Sonographic Differential Diagnosis
Core biopsy of lung masses is a safe procedure as long as the sonographer has a solid window to sample and is able to follow the needle in a clear direct path into the pathology with adequate distance for the need to discharge wihtin the lesion as we see here in this case. Post procedural pain meds are recommended since intercostal approaches tend to be more painful to the patient but very useful for the sonographer. Common etiologies of hypercalcemia include humoral hypercalcemia of malignancy (HHM), hypoadrenocorticism, chronic kidney disease, hypervitaminosis D, and primary hyperparathyroidism. Less common etiologies include bone neoplasia, osteomyelitis, hypertrophic osteodystrophy, granulomatous disease, calcium supplementation, and oral phosphate binders.