SEATTLE — Induction therapy prior to surgery does not extend survival or reduce recurrence among patients with locally advanced thymomas, according to results of a retrospective review presented at the American Association for Thoracic Surgery Annual Meeting.
Giovanni Leuzzi, MD, a thoracic surgeon at IRCCS Regina Elena National Cancer Institute in Rome, and colleagues reviewed data on 370 patients treated at 38 institutions. All patients underwent surgery for stage III thymomas (WHO classification A to B3).
Eighty-eight patients (23.8%) received induction therapy and 245 patients (66.2%) received adjuvant therapy.
Overall, cancer-specific survival was 88.4% at 5 years and 80% at 10 years. RFS was 83% at 5 years and 71.5% at 10 years.
Researchers reported lower rates of 5-year cause-specific survival (85% vs. 88.3%; P = .82) and 5-year RFS (77.9% vs. 84%; P = .31) among patients who underwent induction therapy.
Multivariate analysis showed receipt of adjuvant therapy (HR = 2.44; 95% CI, 1.32-4.48) and completeness of resection (HR = 2.15; 95% CI, 1.16-4) independently predicted cancer-specific survival. Results showed pathologic microscopic invasion — assessed by T classification based on the IASLC/ITMIG TNM staging proposal — was the strongest predictor for relapse (HR = 2.49; 95% CI, 1.19-5.21).
When Leuzzi and colleagues adjusted cancer-specific survival for T classification, results revealed a significant survival advantage associated with receipt of adjuvant therapy. However, among patients whose thymomas measured larger than 5 cm, researchers reported no significant difference in 5-year cancer-specific survival between those who received adjuvant therapy and those who did not (87.1% vs. 91.8%; P = .67).
“The results of the present study indicate that induction therapy does not affect survival and recurrence rate in locally advanced thymomas,” Leuzzi and colleagues concluded. “Based on the reported survival advantages, adjuvant therapy should be administered whenever possible, especially for tumors smaller than 5 cm. Further prospective studies are needed to confirm this preliminary data.” – by Mark Leiser
Leuzzi G, et al. Abstract 20. Presented at: American Association for Thoracic Surgery Annual Meeting; April 25-29, 2015; Seattle.
Disclosure: The researchers report no relevant financial disclosures.