Invasive thymoma: A clinical study of 23 cases

Background. Invasive thymoma is a rare mediastinal tumor. Clinicopathologic al characteristics that influence survival of patients with this tumor are under debate. Treatment is based on tumor resection. The benefice of therap ies, such as radiation therapy (RT) and/or chemotherapy (CT) as adjuvant tr eatments to surgery, or palliative therapy to unresectable or recurrent thy moma are discussed. Objectives: The aim of this study was to assess patient s with invasive thymoma, with specific emphasis on factors predicting survi val. Methods: We studied retrospectively 23 patients with invasive thymoma. Parameters assessed were age, presenting symptoms, histological features, stage at diagnosis, treatment modalities and survival. All patients receive d primary therapy: 11 patients (48%) had tumor resection associated with CT and/or RT, while 12 patients had palliative therapy including RT and/or CT . Regimens for CT were based on cisplatin. Results: Patients' mean age was 58 years. Three patients had stage 11 disease at diagnosis (13%), 8 patient s had stage III (35%) and 12 patients had stage IV (52%). Median overall su rvival was 20 months (range: 4-160) and five-year survival rate was 43.5% ( 10 patients). Surgical resection had a significant impact on survival (p < 0.0001). Survival was also related to stage of the disease at diagnosis (p = 0.006), but not to histology of the tumor (p = 0.12). Salvage treatment w as of clinical importance: 5 out of 15 patients (33.3%) who relapsed during a 5-year follow-up responded to a multimodality therapeutic approach that affected survival (p = 0.019). Conclusion: Factors determining the outcome of these tumors are the stage of the disease at diagnosis, and the adequacy of surgical removal. Salvage treatment of recurrent thymoma may give a mod erate response rate and improve survival. Copyright (C) 2001 S. Karger AG, Basel.