[Malignant retroperitoneal teratoma].

The writers point out a case of malignant teratoma of retro-peritoneal origin and lateral-cervical metastasis. Preliminary tests had shown a mass of a big orange, size of cystic appearance on the scan, clearly defined by TAC, as an oval shape, of cystic appearance, with semiliquid contents, strictly connected with the left-hand side of the thyroid gland and the big vessels of the neck and the fossa over the collar bone plane which pressed on the trachea and put it out of its original position. The needle suction cytologic test, had diagnosed a carcinoma slightly differentiated. After the difficult surgical dissection because of the proximity of the mass to the thyroid gland the trachea and the large vessels, and especially because of the sizable dislocation in mediastinum up to the level of the pleural cupola, the mass was diagnosed after surgery and histological tests as a branchial carcinoma. After a short while, the onset of an abdominal mass, followed soon after by the patient's death, allowed us to look at the case again and to conclude that it was an extra-peritoneal malignant teratoma with a lateral-cervical metastasis.