A case of metastasizing ovarian granulosa cell tumour in the myocardium of a bitch.

Clinical examinations including X-ray analysis, gross pathological, histopathological and ultrastructural investigations were performed on a case of ovarian granulosa cell tumour in a 5-year-old German boxer bitch. Radiographic examination of the abdomen revealed a round, sharply demarcated formation about 4-5 cm in size. The tumour of the left ovary was of a malignant granulosa cell type, with numerous metastases 5-20 mm in size, present in the myocardium (left ventricle), lungs (in all lobes) and prescapular lymph node. Ultrastructural characterization of the tumour demonstrated closely packed cells, with rough endoplasmic reticulum, indicating markedly enhanced protein synthesis probably associated with rapid cell proliferation.