Bizarre patient: she has teeth growing outside her mouth

A 38-year-old woman presents to hospital in Goettingen, Germany. For a long time she has suffered from pain dull in the left hip. Hospital radiologists take her in to perform a radio and an MRI of the hip to figure out what’s wrong. The images taken by the radiologists reveal something unusual. On the ovary left, the patient has a lump of 4.5 centimeters from which two perfectly formed teeth protrude. How is it possible ?

Teeth on the ovary, in the brain…

reported in BMJ Case Reportsthis case describes the formation of a teratomaa type of tumor which forms from pluripotent germ cells which can develop into one or more cell types belonging to the three primordial layers: theectodermthe mesoderm and theendoderm. Concretely, the teratoma can produce skin cells, bones, hair, fatty or connective tissues, nerves and teeth like here.

Teratomas are classified into three groups: immature, mature and monodermic. Our patient developed an immature teratoma which is not cancerous like the immature teratoma is. The latter represent only 1 to 2% of teratomas. The precise origins of teratomas are not known, making their prevention hard. Most cases of teratoma are discovered if patients complain of unusual pain or during another medical examination.

To remove the teratoma, the surgery is required to withdraw the mass and prevent it from becoming cancerous. In our case, the patient had to have her left ovary removed by laparoscopy to remove the entire teratoma, which left no traces of malignant cells behind.

Teratomas can form elsewhere than on the ovariesat the level of a testicle for example or in the brain, like Irish doctors report who treated a 16-year-old girl with a mature intracranial teratoma that also developed two teeth. Although impressive, teratomas are most often benign. The cases described in the literature mainly concern patients aged 30 to 50 years, without distinction of sex. But babies may be born with teratomas, sometimes of considerable size. Again, the only solution is surgery.