OVARY, DERMOID CYST OF THE

Tumour that develops from a totipotential germ cell (a primary oocyte) retained within the egg sac (ovary). Being totipotential, that cell can give rise to all orders of cells necessary to form mature tissues and often recognizable structures such as hair, bone and sebaceous (oily) material, neural tissue and teeth. Dermoid cysts may occur at any age but the prime age of detection is in the childbearing years. The average age is 30. Up to 15% of women with ovarian teratomas have them in both ovaries. Dermoid cysts can range in size from a centimeter (less than a half inch) up to 45 cm (17 inches) in diameter. They can reason the ovary to twist (torsion) and imperil its blood supply. Although the big majority (about 98%) of ovarian teratomas are benign, the remaining fraction (about 2%) becomes cancerous (malignant). The larger the dermoid, the greater the risk of rupture with spillage of the greasy contents which can make problems with adhesions, pain etc. Removal is generally the treatment of choice by laparotomy (surgery) or laparoscopy (with a scope). Dermoid cysts of the ovary are also called simply dermoids or ovarian teratomas.