Therefore, we performed a comprehensive PubMed literature search to find additional data on grade 3/4 neutropenia and FN rates in SCLC patients treated with first-line intravenous etoposide/ platinum regimen (etoposide dosage 240 to 420 mg/m2 per cycle) without concurrent radiotherapy and G-CSF primary prophylaxis. This evidence concerns the gene CSF3 and neutropenia.