A non-invasive huge thymoma with a natural history of fifteen years in an elderly patient

Abstract

We encountered a case of huge non-invasive thymoma incidentally discovered in a female patient during breast cancer surgery. The anterior mediastinal tumor was detected in a pre-operative examination for left mammary cancer excision at another hospital in 1984 when the patient was 72 years old . The clinical progress of the case was followed at regular intervals for 2 years postoperatively using thoracic CT. However, the patient was not examined at all after the transfer of the physician in charge to another hospital . From 1998, expectoration increased and exertional dyspnea appeared and in May 1999 pneumonia-like symptoms and hemoptysis also appeared. The patient was admitted to our department in July 1999, and on admission thoracic CT showed a 15-cm tumor on the left side of the anterior mediastinum and obstructive pneumonia in the lower lung. In August 1999, the tumor (15×10×10cm) was resected via a median sternotomy and left transversal thoracotomy. Pathological examination showed a spindle cell type thymoma with no capsular invasion and based on this finding diagnosed the stage as Masaoka's Clinical Stage I . No recurrence or symptoms have been noted in the 2 years since the operation . The clinical properties of non-invasive thymoma are discussed.