A Case of Invasive Thymoma with Endotracheal Polypoid Growth
A 26-year-old female patient had dyspnea three weeks ago, and underwent a chest computed tomography (CT) scan at the emergency unit of other hospital. A mediastinal tumor that had invaded the trachea was discovered, and the patient was referred to our hospital. The patient had a history of thyroidectomy six years ago, but there was nothing significant to report in her family history. She did not drink alcohol or smoke. Her blood pressure at the time of hospital visit was 115/65 mm Hg, with pulse rate of 100 beats/min, a respiration rate of 24 breaths/min, and a body temperature of 37.0℃. According to the physical findings, she was acutely sick, but was alert, and the conjunctiva of both eyes and lips were not pale. There were neither facial, cervical swelling and nor jugular vein ectasia. Stridor was audible in both upper lung fields and heart sound was normal. Her abdomen was flat, bowel sound was normal, and no tenderness or rebound tenderness was observed in her abdomen. She had no hepatosplenomegaly and no lump. According to the laboratory findings, her hemoglobin count was 13.1 g/dL; white blood cell count, 11,820/mm3 (77.4% neutrophils, 12.7% lymphocytes, and 0.9% eosinophils); platelet count, 249,000/mm3; and C-reactive protein, 1.2 mL/dL. In the arterial blood gas analysis that was performed immediately before the hospital visit, the pH was 7.404; PCO2, 38.7 mm Hg; PO2, 52.9 mm Hg; HCO3, 23.7 mEq/L; and SaO2, 87.7%. According to the biochemical analysis, the total serum protein was 7.0 g/dL; albumin, 3.9 g/dL; aspartate aminotransferase, 14 IU/L; alanine aminotransferase, 3 IU/L; blood urea nitrogen, 6 mg/dL; creatinine, 0.6 mg/dL; and lactate dehydrogenase, 347 U/L. On the chest X-ray image, volume reduction of the right upper lobe and tracheal deviation to the right were observed, and a lump was suspected on the right wall of the trachea. The superior mediastinum on the chest CT scan (performed in other hospital) showed tracheal stenosis and invasion of a uniform mass with a relatively clear boundary that measured approximately 3.3 cm ().\nOn the second day of the patient's hospitalization, bronchoscopy was performed, and tracheal stenosis accompanied by a polypoid tracheal tumor that was blocking the lumen in the middle of the tracheal tube was observed (). An endoscopic tissue biopsy was performed, and the result of the tissue test showed chronic inflammation that included fibrin exudation. On the third day of the patient's hospitalization, fiberoptic bronchoscopy was performed again for the histological diagnosis, but only chronic inflammation with granulation tissue was observed. A definite diagnosis cannot be confirmed from the tissue biopsies that were performed twice, and on the fifth day of the patient's hospitalization to relieve upper airway obstruction and for the histological confirmation, tracheal tumor resection and end to end anastomosis were performed at the Department of Thoracic Surgery at our hospital. The final post-operative tissue findings showed type B3 thymoma of the World Health Organization (WHO) classification which appeared to have intruded up to the subepithelial region of the trachea (~).\nAfter the surgery, the patient's symptoms improved; and a month after the surgery, four cycles of adjuvant chemotherapy were carried out with a combination of cyclophosphamide (500 mg/m2), doxorubicin (50 mg/m2), and cisplantin (50 mg/m2). A relapse of the cancer was found in the operation site on the chest CT scan six months after the surgery, and the patient underwent radiotherapy with a total radiation level of 7,200 cGy for eight weeks. The patient is now under outpatient follow-up with complete remission since September 2010.