[Clinico-pathologic characteristics of malignant thymoma].
OBJECTIVE
To assess the histopathology, clinical staging and treatment of malignant thymoma in relation to prognosis.


METHODS
Sixty four cases with malignant epithelial thymic tumors treated in the period of 1958-1995 were retrospectively studied. Archived specimens were categorized according to Levine and Rosai into type I malignant thymoma(MT) and type II thymic carcinoma (TC). MT was histologically classified according to Müller-Hermelink(M-H). Clinical staging was ascertained according to Masaoka's criteria.


RESULTS
There were 41 cases of MT and 23 cases of TC. No medullary or mixed thymoma was observed in this series of MT. The 5-year survival rate of patients with MT of predominantly cortical, cortical, and well-differentiated thymic carcinoma (MDTC) subtypes was 75.3%, 44.7% and 43.3%, respectively. That of patients with TC of squamous-cell carcinoma and lympho-epithelioid subtypes was 27.5% and 60.0%, respectively. The 10-year survival rate of these 5 subtypes was 25.3%, 10.0%, 0, 0, 20.0%, respectively(P < 0.05). The 5-year and 10-year survival rates decreased with increase in staging. In 22 patients in stage III and IV who received thoracotomy with biopsy only, their survival rate was significantly lower than that in patients with their tumor resected.


CONCLUSIONS
Histomorphology of the tumor, heterogeneity in cell types, clinical staging and the extent of tumor resection are factors affecting survival.
Lin
D
D
Department of Pathology, Cancer Institute (Hospital), Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100021.
Lü
N
N
Feng
X
X
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015996:Survival Rate; D013945:Thymoma / Q000401:mortality / Q000473:pathology*; D013953:Thymus Neoplasms / Q000401:mortality / Q000473:pathology*