Comparison of neoadjuvant chemotherapy followed by surgery to upfront surgery for thymic malignancy.

BACKGROUND: The oncological benefit of neoadjuvant chemotherapy in thymic malignancies remains unclear. We compared postoperative oncological outcomes of curative resection following neoadjuvant chemotherapy with those of upfront surgery.

METHODS: Based on records from a multi-center database, a total of 1486 patients with surgically resected thymic malignancies between 2000 and 2013 were included in the final study cohort. 110 (7.4%) patients underwent surgical resection following neoadjuvant chemotherapy and 1376 (92.6%) patients underwent upfront surgery. A propensity score-matched analysis was performed to minimize differences in preoperative and intraoperative variables. Postoperative outcomes and survivals were compared between the two groups.

RESULTS: In the matched cohort, there were no significant differences in postoperative mortality (p-value not calculated), postoperative complication rates (p = 0.405), and length of hospital stay (p = 0.821) between the two groups. However, the neoadjuvant chemotherapy group showed significantly higher transfusion rates (p = 0.003) and longer operation times (p < 0.001) than the upfront surgery group. Pathologically complete resection rates (p = 0.382) and tumor sizes (p = 0.286) were similar between the two groups. The 5-year overall survival rates were 77.4% and 76.7%, respectively (p = 0.596). The 3-year recurrence-free survival rates were 62.9% and 71.5%, respectively (p = 0.070).

CONCLUSIONS: Neoadjuvant chemotherapy followed by resection obtained similar resectability and long-term survival rates to those of upfront surgery. Therefore, the role of neoadjuvant chemotherapy should be refined in randomized controlled trials.