Echographic aspects of thyroid and parotid localizations in non-Hodgkin lymphomas

The authors present four observations of rare localizations of non-Hodgkin lymphomas (3 cases of lymphoma of the thyroid, 1 case of lymphoma of the parotid), all of which were studied by echography. In two of the thyroid localizations, the echographic pattern was identical to that observed for nodes in non-Hodgkin lymphomas, and thus differs from that of cysts and necrotized or cystic tumors. In the one case of secondary lymphoma of the thyroid, accompanied by diffuse enlargement of the gland but no histological proof, echography revealed only diffuse enlargement, without any anomaly in the echostructure. In the one case of lymphoma of the parotid, the echographic image was similar to that of a lymphomatous node, but it cannot be formally differentiated from the structure which can be observed for a mixed tumor or a cystic lymphangioma.