PCI and Brain MRI Follow-up vs Brain MRI Follow-up Alone in Limited-stage SCLC Patients

At present, prophylactic cranial irradiation (PCI) is part of standard care for patients with limited-stage small cell lung cancer (SCLC) who have achieved good response after definitive thoracic radiotherapy and chemotherapy. However, the value of PCI is being challenged in the era when MRI examination of brain has been popularized. The goal of this clinical study is to compare PCI and regular brain MRI follow-up (control arm) and regular brain MRI follow-up alone (study arm) in patients with limited-stage SCLC who have received definitive radiotherapy and chemotherapy and acheived complete remission (CR) of tumor. The main questions to answer are: 1. Whether the 2-year brain metastasis-free survival rate of the study group is not inferior to that of the control group. 2. The difference of 2-year overall survival rate between the control group and the study group. 3. Whether the patients in the study group have better overall quality of life than those in the control group. Participants will randomly receive either PCI and regular brain MRI follow-up or regular brain MRI follow-up alone.