Guo D, et al. - In small cell lung cancer (SCLC) patients who received prophylactic cranial irradiation (PCI) researchers assessed the clinical value of carcinoembryonic antigen (CEA) for predicting brain metastases (BM) and survival via analyzing the records of 128 consecutive SCLC subjects who had PCI in the institute between 2005 and 2015. Results of this study suggested that CEA is an independent predictive factor for the incidence of BM following PCI in SCLC patients and has predictive value for BM in SCLC. Following PCI, a high level of CEA shows a poor prognosis in SCLC patients.