Similar results were gained in oligo-progressive and oligo-metastatic NSCLC with EGFR mutations; for instance, the randomized SINDAS trial, which found that preemptive RT before the occurrence of oligo-progression improved OS and PFS in these populations [19], although the definitions of oligo-metastatic and oligo-progression varied among studies. Here, EGFR is linked to non-small cell lung carcinoma.