Outcome of multimodality treatment for 188 cases of type B3 thymoma.
BACKGROUND
This study aimed to evaluate the long-term efficacy of multimodality therapy for patients with type B3 thymoma.


METHODS
A total of 188 consecutive patients with type B3 were treated in our hospital from January 2001 to December 2010. One hundred seventy-seven patients who had been treated with curative intent were retrospectively analyzed. According to World Health Organization Classification, all patients were pathologically confirmed as type B3. Distribution of Masaoka stages I, II, III, and IV was 35 (19.8%), 20(11.3%), 78 (44.1%), and 44 (24.8%), respectively. Myasthenia gravis coexisted in 34% of patients.


RESULTS
After a mean follow-up of 49 months (7-135 months), the 10-year overall survival (OS) rates were 65% (89%, 86%, 61%, and 42% in stage I, II, III, and IV, respectively). One hundred five patients patients (102 patients with R0 resection and 3 with complete response after radiotherapy) were analyzed for freedom from recurrence (FFR). The 5- and 10-year FFR rates were 91% and 73% (100%, 94%, 84%, 71% and 100%, 94%, 56%, N/A in stages I, II, III, and IV, respectively. We have no data of stage IV.) TTP was calculated on 72 patients including 57 patients with R+ resection and 15 with partial response or stable disease after radiotherapy. The 5-year time-to-progression (TTP) rates were 33% (41%, 24% in stage III and IV, respectively). Multivariate analysis showed that prognostic factors for OS were the Masaoka stage and adjuvant radiation for patients with stage III and IV. The Masaoka stage and resection margin after surgery had significant effects on FFR and TTP.


CONCLUSIONS
The type B3 thymoma often presented with the later stages at the diagnosis. The Masaoka stage was closely associated with OS, FFR, and TTP. Resection margin after surgery was related to TTP. Adjuvant radiotherapy may be beneficial to stage III and IV patients in this clinical setting.
Departments of *Radiation Oncology, †Surgery, ‡Pathology, Chest Hospital of Jiao Tong University, Shanghai, China; and §Department of Radiation Oncology, Sixth Hospital of Jiao Tong University, Shanghai, People's Republic of China.
Lanting
L
Gao
Changlu
C
Wang
Wentao
W
Fang
Jie
J
Zhang
Changxing
C
Lv
Shen
S
Fu
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D009367:Neoplasm Staging; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D012189:Retrospective Studies; D015996:Survival Rate; D013934:Thymectomy; D013945:Thymoma / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D013953:Thymus Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D055815:Young Adult