Renal microcystic tubular lesions in two 1-year-old dogs - An early sign of hereditary renal cystadenocarcinoma?

As a part of a study of early renal changes in renal cystadenocarcinoma (RC ), a 5-year-old German shepherd dog and two 1-year-old German shepherd mixe d-breed dogs were examined. All thr ce animals had bilateral, microscopic r enal cysts, and the 5-year-old dog also had RC. Microscopical examination s howed papillary hyperplastic tubular epithelial cells lining the inner wall of the renal cysts in all dogs. These cells showed strong reactivity with a monoclonal antibody against a broad-spectrum type of cytokeratin. The dam of the young dogs had suffered from autosomal dominant inherited RC and no dular dermatofibrosis (ND) syndrome. It is likely that the microscopic rena l cystic lesions seen in the young dogs represented an early renal change i n the RC/ND syndrome. This suggests that the diagnosis of RC can be made on suspected carriers by microscopical examination of renal biopsies as early as 1 year of age, i.e., before the dogs are used for breeding. (C) 2000 Ha rcourt Publishers Ltd.