We report a patient with a widened mediastinum secondary to a rare and benign condition known as mediastinal lipomatosis (ML). ML is caused by accumulation of adipose tissue within the mediastinum. Case reports associate JvlL with obesity, diabetes, Cushing's syndrome, steroid use while other cases remain idiopathic.'.. We report a patient with Glioblastoma Multiforma (GBM) on chronic steroids, who was found to have ML on imaging despite lack of obesity or Cushing's syndrome. This case provides significant educational benefit in approaching a patient with a widened mediastinum.

Case Presentation

A 59-year-old male with a history of recurrent GBM status post stereotactic radiation and ongoing chemotherapy presented to the hospital with lethargy, altered mental status and expressive aphasia consistent with ongoing progression of his malignancy. The patient was not obese (weight 72.1 kg; height 6'1", body-mass index 21), non-diabetic, and had been on a daily dose of2-8mg of dexamethasone intermittently (equivalent to prednisone 25-SOmg daily) for approximately a year and half forGBM.