Benign/mature cystic teratoma- ovary
Teratomas are the tumors which have tissues which are representative of more than one germ cell layer. And it can contain tissues from all the germ cell layers. The tissues are haphazardly arranged.
Gross: these are usually unilocular tumors, cystic with smooth surface. On cut section, they contain cheesy/pultaceous material with variable amount of hairs. Areas of round nodular structure can be seen which protrudes into the lumen. These are called Rokitansky protuberance. They may be covered with hair. Rarely tooth and areas of calcification can be seen.
Microscopy: shows evidence of structures derived from the various germ cell layers. The cyst wall is usually stratified squamous epithelium with appendages like hair follicles and sebaceous glands. Derivatives of ectoderm, endoderm and mesoderm are seen in varying proportions as seen in the illustration above.