[An analysis of clinicopathologic features affecting prognosis of thymoma].

OBJECTIVE

To discuss the relationship between the clinicopathologic characteristics and prognosis of thymoma.

METHODS

One hundred and thirty cases of thymoma were analyzed in terms of myasthenia gravis(MG), tumor size, necrosis, mitosis, capsule, histologic type according to the Lattes-Bernatz(L-B) classification and Muller-Hermelink(M-H) classification, staging according to Masaoka.

RESULTS

Association with MG, size of tumor, necrosis, mitosis and L-B classification were of no prognostic significance. The survival rate was higher in patients with a well encapsulated tumor. According to the M-H subtypes, the prognosis was better in patients in medullary type than in patients with cortical type thymoma. In patients with well-differentiated thymic carcinoma(WDTC), their 5-year survival rate was 43.4%, and none survived at 10 years. The survival of patients decreased with the increase in clinical stage of the disease. Cell atypia and invasion of neighboring organs were of prognostic impact on survival.

CONCLUSION

Histologic typing according to M-H classification and clinical staging according to Masaoka, cell atypia and invasion to neighboring organs are of prognostic value in patients with thymoma.