[A case of forgotten giant goiter].

The forgotten goiter is most often the consequence of the incomplete removal of a "plunging" goiter, but it can sometimes be attributed to a concomitant, unrecognised mediastinal goiter which is not connected to the thyroid. Differential diagnosis must be made with other mediastinal masses and with plunging relapses of a previously operated struma. Radiological analysis of persisting mediastinal involvement before and immediately after surgery is the only decisive means of diagnosis, but this is not always available in practice. In this paper the authors report a case of considerable size observed in a series of 346 mediastinal goiters operated between 1967 and 1994. They examine the pathogenetic aspects and the nosological, diagnostic and therapeutic problems related to forgotten goiter, and lastly they list the recommendations that several surgeons have made in an attempt to reduce the incidence. In conclusion, the systematic use of CAT or NMR in the diagnosis of mediastinal opacity may help to reduce the risk of forgetting glandular residue in the mediastinum.