What is the role of radiation in a patient with limited stage small cell lung cancer initially treated with chemotherapy alone and received a complete response based on CT and PET-CT?

From the 1990's SCLC studies of Ralph Johnson at the Radiation Oncology Branch, and then a later NCI re-analysis of that 100 patoient data set, the pattern of concurrent for 3-4 weeks was better than a longer period of time, or a shorter period of time including sequencing for many cycles followed ...