Wang H, et al. - Researchers used the 2010-2013 Surveillance, Epidemiology, and End Results (SEER) database to examine the traits and prognosis for survival of patients with clinical tumor size 0 (cT0) extensive-stage small cell lung cancer (ES-SCLC) with distant metastasis. They found that patients at cT0 stage represented a different subgroup vs patients at cT1-4 stage for ES-SCLC with distant metastasis. In cT0 stage, the identified risk factors were clinical nodal status 0 (cN0) stage, no bone metastasis and no lung metastasis. In addition, cancer specific survival (CSS) was found to be better among patients at cT0 stage, which was also identified as an independent prognostic factor on CSS.