Correct!
2. Intrathoracic goiter
Among the choices listed, intrathoracic goiter is least likely to be responsible for the findings at the thoracic CT because the mediastinal lesion is clearly spatially separated from the normal thyroid gland, seen superiorly and anteriorly from the mass. Intrathoracic goiter extension is almost always closely associated with, and is usually seen in contact with, the normal thyroid gland in the inferior neck. Very rarely, ectopic thyroid tissue could account for a thyroid goiter that does not contact the normal thyroid gland, but such occurrences are exceeding rare and, when present, are often anteriorly located. A mediastinal abscess, due to esophageal pathology or adjacent osteomyelitis, may present in this fashion. Non-Hodgkin lymphoma is more typically associated with multi-compartmental lymph node enlargement, rather than an isolated superior – posterior mediastinal soft tissue mass, whereas Hodgkin lymphoma more commonly presents as an anterior mediastinal mass. However, atypical presentations of common disorders, such as non-Hodgkin lymphoma, suggest that the unusual presentation of non-Hodgkin lymphoma as a superior posterior mediastinal mass may occasionally occur. Given the proximity of the soft tissue mass to the posterior portion of the esophagus, a neoplasm arising from the esophagus is a leading consideration. Finally, while more commonly off-midline in a paraspinous position, a neurogenic neoplasm could present in this manner.
Which of the following would be most useful to determine the etiology of the superior posterior soft tissue mediastinal mass? (Click on the correct answer to proceed to the sixth of eight panels)