43 year old woman was found on routine gynaecological checkup to have an ovarian mass. Ultrasound showed a markedly enlarged, predominantly cystic ovary.
The unilocular ovarian cyst shows small clusters of whitish papillary excrescences arising from the inner surface of the cyst wall. The cyst would have been filled with clear, thin serous fluid. No solid fleshy mass is seen. The wall of the cyst is intact.