IGF1R and small cell lung carcinoma: Compared with the ADC tumors, the frequency of positive RTKs among the LCNEC and SCLC tumors was significantly higher for c-Kit (LCNEC: 49 %, SCLC: 47 %, and ADC: 3 %), IGF1R (LCNEC: 31 %, SCLC: 28 %, and ADC: 5 %), and KDR (LCNEC: 29 %, SCLC: 38 %, and ADC: 1 %) and lower for ERBB2 (LCNEC: 6 %, SCLC: 2 %, and ADC: 17 %), FGFR1 (LCNEC: 2 %, SCLC: 0 %, and ADC: 35 %), c-Met (LCNEC: 2 %, SCLC: 6 %, and ADC: 43 %), and ROS1 (LCNEC: 0 %, SCLC: 0 %, and ADC: 40 %).