PREDICTORS OF SURVIVAL FOLLOWING SURGICAL RESECTION OF THYMOMA

The aim of this study was to determine the predictors of long-term sur vival following surgical resection of thymoma. Forty-one patients with a histologically proven diagnosis of thymoma were evaluated and treat ed over a 30-year period (1961 to 1991) at our institution. Seven pati ents (Masaoka stage m or IV) were unresectable and were treated by rad iotherapy and/or chemotherapy, with an overall 5 year survival of 50%. Thirty-four patients underwent primary surgical excision of the thymo ma, most often through a median sternotomy, with 5- and 10-year surviv als of 90%. Complete excision of the thymoma was achieved in 31 patien ts with a median survival of 54 months vs. 17 months if incomplete. In dependent prognostic factors influencing survival were stage, histolog y, and patients judged to have a benign thymoma at surgery. Although t he thymoma was associated with myasthenia gravis (8 patients) and seco nd primary cancers (8 patients), neither factor was associated with ov erall survival. We conclude that the most significant predictors of lo ng-term survival of thymoma include complete excision, Masaoka stage I disease, and lymphocytic histology. Multivariate analysis suggested t hat postoperative chemoradiotherapy may impact on survival. (C) 1993 W iley-Liss, Inc.