In fact KRAS mutations have been previously associated with a higher CRC metastatization rate both in lung parenchyma 8, 9, 10, 11, 12, 13, 14, 15 and CNS 9, 11, and a significant association between KRAS mutations and relapse in the lung have also been reported 8, 9, 15. The gene discussed is KRAS; the disease is colorectal carcinoma.