Case Study

Renal mass suspect carcinoma in a 6 year old DMH cat

A 6-year-old FS DMH cat was presented for evaluation of one-week duration of decreased appetite. On physical examination, grade 2-3/6 heart murmur and a palpable mass in the cranial to mid abdomen was present. The only abnormality on blood work was hypercalcemia (corrected calcium 15.6). Survey thoracic radiographs showed 2.3 x 2 inch soft tissue abdominal mass.

Image Interpretation

The right kidney in this patient presented a complex, mixed, hypoechoic nodular mass with subcapsular fluid accumulation with complete distortion of architecture. The right kidney measured 7.0 cm in its entirety. Significant capsular expansion was noted in this patient with pericapsular inflammatory pattern, yet no capsular escape was noted. This appears to be potentially resectable. However, adhesions against the body wall may be an issue. The left kidney presented a focal, hypoechoic nodule at the caudal pole with capsular retraction. The left kidney measured 3.8 cm.

DX

Focal hypoechoic nodule at the caudal pole of the left kidney with capsular retraction. Right renal mass, suspect carcinoma, possible sarcoma. Pericapsular inflammatory pattern

Outcome

FNA of only the nodule in the left kidney is recommended to assess if this is a neoplastic process or an inflammatory or degenerative process. If this is not a neoplastic process then a right nephrectomy should be attempted or direct right nephrectomy with adjunctive chemotherapy if the patient is chemoresponsive. Three view chest radiographs would be warranted as a screening procedure. An inflammatory pattern from the right renal capsule against the body wall is a concern. Portions of the body wall may need to be removed for full surgical resection. There is no contraindication to anesthetic procedure. Guarded prognosis.

Clinical Differential Diagnosis

Mass – neoplasia/granuloma of kidney, pancreas, spleen, liver, lymph node, mesentery, small intestine
Murmur – physiological, cardiomyopathy, endocarditis