Analysis of long-term outcomes and application of the tumor regression grading system in the therapeutic assessment of resectable limited-disease small cell lung cancer

Abstract

Abstract Objective The present study attempted to evaluate the value of neoadjuvant chemotherapy in limiteddisease small cell lung cancer (LD-SCLC), and to identify the predictive value of the tumor regression grading (TRG) system in LD-SCLC treatment-response and prognosis. Methods The records of patients with LD-SCLC (p-Stage I-IIIa) who underwent definitive radical resection at Shaanxi Provincial People’s Hospital between March 1, 2000 and March 31, 2014 were retrospectively analyzed. We compared the disease-free survival (DFS) and overall survival (OS) rates between Group A patients (patients who underwent surgery combined with pre- and post-operative chemotherapy) and Group B patients (patients who underwent surgery combined with adjuvant chemotherapy only) using the Kaplan-Meier method and the Mantel-Cox test. The specimens of patients who received neoadjuvant chemotherapy were reassessed according to the TRG system. Results The median DFS for 27 patients was 16.267 months and the median OS was 81.167 months (1-year OS, 74.07%; 3-year OS, 22.22%; 5-year OS, 14.81%). Thirteen patients received neoadjuvant chemotherapy, and their specimens were reassessed by TRG (pathological complete remission, 3/13, 23.08%). Patients in group A had a longer OS than those in group B (mean, 93.782 months versus 42.322 months, P = 0.025), although there was no significant difference in DFS between the two groups (median 20.100 months versus 14.667 months, P = 0.551). Statistical analysis revealed that TRG Grade (G) 0 (mean, 61.222 months) was associated with better OS than G1-2 (mean, 31.213 months) (P = 0.311). Conclusion Our study indicated that neoadjuvant chemotherapy combined with surgical resection may represent a feasible treatment method for patients with LD-SCLC. The TRG system may be a valuable prediction tool to assess neoadjuvant chemotherapeutic efficacy, especially in patients with G0 disease as determined by TRG; these patients may attain an improved survival benefit with neoadjuvant chemotherapy.