RB1 and small cell lung carcinoma: The largest cohort of NGS testing on ctDNA obtained from SCLC patients was described by Devarakonda et al. Out of 609 liquid biopsies obtained from 564 patients, at least one non-synonymous mutation or amplification was detected in 91% of the samples, with mutations of TP53 (72%) and alterations in RB1 (18%) being the most common.