EGFR and breast cancer: In the cases of lung cancers, EGFR mutations and ALK rearrangements were also identified.78, 79, 80 ctDNA concentration was significantly increased in other types of cancers such as periampullary cancer,81 oesophageal cancer,82 head and neck cancer,83 renal cancer,84 melanoma85 and prostate cancer.86 Besides, high LOH frequencies, particularly the observed CCND2 loss, were associated with the aggressiveness of breast cancer.87