A 27-year-old man was admitted to Yong Dong Severance Hospital, Yonsei University Medical Center, for evaluation and management of mediastinal mass.
Three years prior to admission, he found mediastinal mass on computerized tomographic (CT) scan performed in another institution.
At admission, he was noted to be with generalized weakness and right chest pain, but he denied cough, sputum and dyspnea.
The temperature was 38.6 C, the pulse rate 72/min and the blood pressure 110/70 mmHg.
On examination, he appeared chronically ill, the skin was warm and dry, the head and neck were normal and cervical lymphadenopathy was not found, the lungs were clear and the heart was normal.
The abdomen and extremities were normal.
The urine was normal and the hemoglobin was 13.5gm/dl; hematocrit 41.9%; white cell count 5,500/mm3 with 64 percent neutrophils, 35 percent lymphocytes and 1 percent eosinophils, the serum electrolytes and liver function tests were normal. T3: 150 ng/dl, T4: 7.1 ug/dl, FT4: 1.6ng/dl and TSH was 1.5 uU/ml.
The electrocardiogram showed right axis deviation and tall R wave in right precordial leads, and the sputum exanination did not suggest malignancy or tuberculosis.
Chest roentgenogram (Fig. 1) revealed well defined mediastinal mass on the right paratracheal area.
Chest CT scan revealed large multi-cystic mass lesion on the right paratracheal area which was attached to the lower pole of right thyroid gland, displaced the superior vena cava anteriorly and extended to the level of the azygous arch vein (Fig. 2).
The lung perfusion scan and whole body bone scan were normal and the thyroid scan revealed cold area in the lower pole of right thyroid gland.
The fiberoptic bronchoscopy revealed extrinsic mass effect without mucosal lesions on right intermediate bronchus.
The pulmonary function studies showed mild restriction with FEV1:2.85 L/sec and FVC: 3.49 L/sec.
He underwent operation under the impression of mediastinal mass.
8x8 cm sized mass composed of multi-cystic and solid part was located in the pericardium and excised easily from the surrounding structures and the feeding vessel maybe originated from the subclavian artery.
Grossly, the mass was composed of several cystic lesions and yellow solid lesion, resembling unexpanded lung tissues (Fig. 3) and the surface of the mass shows a feeding vessel (Fig. 4).
Mlicroscopically, the cyst wall showed a bronchial tissue which was composed of ciliated columanar epithelium, submucosal gland and cartilage (Fig. 5) and solid portion of the mass showed alveolar space filled with inflammatory cells such as macrophages or lymphocytes (Fig. 6)