CEACAM5 and colorectal cancer: In the group of 16 asymptomatic patients with a history of previously treated colorectal cancer who has a rising CEA, they found recurrent disease in only nine of 16 patients (56.2%) by traditional surgical exploration alone, but in 14 of 16 patients (87.5%) using a combined approach of traditional surgical exploration and RIGS, thus demonstrating that RIGS detected over-looked recurrent disease in five of 16 patients (31.3%) [303].