An ovarian cyst containing old brown blood.
An ovarian cyst with darkly pigmented gelatinous contents.
A distinctive brown swelling can manifest within an ovary, referred to as a chocolate cyst. These cysts commonly develop in individuals with endometriosis, a condition characterized by the presence of endometrial tissue, which normally lines the uterus, in areas outside of the uterus. The brown color of these cysts is attributed to the presence of clotted blood within them, resulting from the abnormal growth of endometrial tissue.