Benign cystic teratoma
Dermoid cysts are benign tumors. They can contain cellular tissue from all 3
germ layers. The most common histology seen is ectodermal skin appendages
(hair, sebaceous glands), thus the name “dermoid.” Gastrointestinal histology
can be identified, and carcinoid syndrome has been described originating from a
dermoid cyst. Thyroid tissue can also be identified, and if it comprises >50% of
the dermoid, then the condition of struma ovarii is identified.