Comparison of oncological results for early- and advanced-stage thymomas: thoracoscopic thymectomy versus open thymectomy.

BACKGROUND

This study evaluated the feasibility of thoracoscopic thymectomy (TT) for the treatment of early- and advanced-stage thymoma and compared patient outcomes with those following open thymectomy (OT).

METHODS

A retrospective review was conducted for 140 patients who underwent TT or OT for Masaoka stage I-IV thymoma between 1996 and 2014.

RESULTS

TT was performed in 88 patients and OT in 52 patients. The postoperative hospital stay was significantly shorter in the TT group than in the OT group (4 and 13 days, respectively; P < 0.0001). WHO types B3-C were identified in Masaoka stage III-IV disease with high frequency. There was a significant relationship between Masaoka stage and WHO type (P < 0.05); the numbers of advanced-stage thymoma progressively increased in WHO type B3-C. Eight patients in each group had recurrent disease, with greater recurrence for WHO types B3-C and stage III-IV tumors. Five-year disease-free survival (DFS) was not different between groups (P = 0.3906); however, survival for patients with stage III-IV thymomas (47 %) was significantly worse than that for patients with stage I and II tumors (97.5 and 94.1 %, respectively; P < 0.0001). Based on multivariate analysis, both Masaoka stage and WHO type were significant predictors of thymoma patient survival.

CONCLUSIONS

These results demonstrate the safety and substantially decreased invasiveness of TT for thymoma. The oncological results were comparable between the TT and OT groups. Furthermore, Masaoka stage III-IV and WHO B3-C were revealed as independent prognostic factors for DFS.