Bilateral Ovarian Cystadenoma in a Dog: Morphological and Histopathological Features

Normal and abnormal cystic structures around the ovaries need to be evaluated based on the history, clinical signs, diagnostic imaging and paraclinical methods. An intact spitz nulliparous female, 9 years old, was referred with a normal estrous cycle and health history. During the ultrasound examination, bilateral cystic structures were observed around the ovaries just caudal to the kidneys. The left-side cystic masses were larger than the right-side and no abdominal free fluid observed. Based on the cystic structures and the age of the dog, an ovariohysterectomy was performed and histopathological samples were prepared for evaluation. Histopathological evaluation revealed multicystadenoma tumors originating from the subepithelial structures of the ovaries. No clinical signs of hormonal activity of cystic tumors were observed. They may affect transportation of oocytes from the ovary to the oviduct due to their physical structures in the ovulation space and infundibulum of the oviduct.