A tumour-agnostic approach targeting KRAS mutations was the most widely used method of ctDNA detection and quantification (n = 36) [23,25,27,28,31,33,34,[39], [40], [41], [42], [43], [44], [45],[48], [49], [50], [51],53,54,57,59,62,63,[65], [66], [67], [68], [69], [70],72,77,78,[82], [83], [84]]. This evidence concerns the gene KRAS and neoplasm.