Lung cancer, being the most common cancer type, accounts for 13% of all newly diagnosed malignant tumors globally each year. Small cell lung cancer（SCLC） accounts for approximately 15% of newly diagnosed lung cancers each year, but its annual death toll accounts for 25% of that of lung cancer. We summarized relevant clinical studies to elaborate the epidemiology, pathological and clinical characteristics and the treatment status of small cell lung cancer. This paper first described the epidemiology and the pathological and clinical characteristics of SCLC and the systematic treatment of extensive-stage SCLC and then introduced the current targeted therapy and immunotherapy for SCLC to provide clinicians and patients with a more systematic, comprehensive, and beneficial treatment regimen. We expect that these studies can provide clinicians with a clear direction in molecularly targeted therapy or immunotherapy, so that a treatment approach with better antitumor effects and longer-lasting clinical benefits can be provided to the patients.

BACKGROUND:There is still a debate regarding whether regimens combining irinotecan with platinum could replace regimens combining etoposide with platinum, as first-line chemotherapy for extensive-stage small cell lung cancer (ES-SCLC). We performed a meta-analysis to compare these regimens as first-line chemotherapy for ES-SCLC.METHODS:A literature search for randomized controlled trials was performed using the Cochrane Library, PubMed, and Embase. The inverse variance method was used to estimate summary hazard ratios and their 95% confidence intervals for overall survival and progression free survival. Relative risk was used to estimate the overall response rate, disease control rate, 1-year survival, 2-year survival, and adverse event data.RESULT:Nine randomized controlled trials (2451 patients) were included. Regimens combining irinotecan and platinum improved overall survival, progression-free survival and overall response rate compared to combination etoposide and platinum regimens. Meanwhile, superior progression-free survival and overall response rate outcomes were observed in the Asian subgroup of patients. These patients receiving a combination irinotecan and platinum regimen experienced grade 3-4 diarrhea more frequently and experienced less hematologic toxic events than the non-Asian groups.CONCLUSIONS:Our data suggest that a combination irinotecan and platinum regimen can prolong overall survival, progression-free survival and overall response rate for patients with ES-SCLC as compared to a combination etoposide and platinum regimen. And the Asian patients could benefit from irinotecan combined with platinum easier.