Co-Existent Symptomatic Large Retrosternal Nontoxic Multinodular Goiter With Mediastinal Lipoma

Abstract

Objective: To present a rare case of a co-existing large retrosternal nontoxic multinodular goiter (MNG) and a large mediastinal lipoma in a woman with compressive symptoms. Methods: The clinical presentation and diagnostic utilization of computed tomography (CT) in the management of this case are presented. Results: A 66-year-old woman was evaluated for slowly progressive, intermittent dysphagia and neck pressure over a period of 4 years. The nodular thyroid gland had been biopsied in the past and noted to be benign. Examination of the thyroid showed a large nodular goiter with an estimated weight in excess of 100 g. Thyroid function tests were within normal limits. A chest radiograph showed a large soft tissue mass in the upper right anterior mediastinum and lower neck with displacement of the trachea to the left. A CT scan with intravenous contrast of the neck and chest showed that the mass was comprised of both a large MNG and a large adjacent fat density mass in the right anterior mediastinum. The fat density mass had uniform fat attenuation with a Hounsfield unit of -112, characteristic of a lipoma. The patient underwent a two-step procedure – near-total thyroidectomy followed by a thoracotomy to remove the large mediastinal fatty mass 2 months later. Conclusion: This case illustrates the possible co-existence of a retrosternal MNG and a large mediastinal lipoma resulting in compressive symptoms. The utilization of CT proved useful in characterizing the fatty nature of the mediastinal mass which was helpful in the surgical management. Abbreviations: CT = computed tomography MNG = multinodular goiter