Associated links among smoking, chronic obstructive pulmonary disease, and small cell lung cancer: A pooled analysis in the International Lung Cancer Consortium
Small cell lung cancer (SCLC) comprises approximately 15–18% of all lung cancers worldwide. SCLC is the most aggressive subtype of lung cancer and is characterized by rapid doubling time, high growth fraction, and early widespread metastasis. Despite high response rates to initial treatment, SCLC usually relapses and becomes refractory to treatment within one year. The median survival is 14–20 months for limited SCLC and 9–11 months for extensive SCLC. These statistics highlight the need for new tools to aid in diagnosis and prevention.