Efficacy of EP Chemotherapy Followed by IP Chemotherapy Combined with Radiotherapy in the Treatment of Extensive-Stage Small-Cell Lung Cancer

To explore the efficacy and safety of etoposide + cisplatin (EP) and irinotecan + cisplatin (IP) sequential chemotherapy combined with radiotherapy in the treatment of extensive-stage small-cell lung cancer (SCLC). A total of 108 patients with extensive-stage SCLC were divided into the EP+IP group (n=54, sequential IP chemotherapy), and the EP group (n=54, EP chemotherapy). The changes in the level of serum tumor markers and the number of circulating tumor cells (CTCs) in the peripheral blood were compared between the two groups of patients before and after treatment. The patients were followed up to record the survival status and tumor progression. The overall effective rate for bone metastases in the EP+IP group was significantly higher than that in the EP group. The EP+IP group displayed significantly lower levels of serum VEGF, Ki-67 and peripheral blood CTCs than the EP group. In addition, the follow-up results manifested that the median overall survival (OS) in the EP+IP group and the EP group were 16.2 months and 12.7 months, respectively, and the median progression-free survival (PFS) was 8.4 months and 5.9 months, respectively. The 2-year OS was 13.0% and 7.4%, respectively. Furthermore, the log-rank test illustrated that the OS and PFS in the EP+IP group were significantly superior to those in the EP group. EP and IP sequential chemotherapy combined with radiotherapy is more effective than EP chemotherapy combined with radiotherapy in the treatment of extensive-stage SCLC. The former can markedly reduce the levels of serum tumor markers and peripheral blood CTCs, increase the long-term survival of patients and reduce the occurrence of blood-related adverse reactions.