Identification of patients at-risk for Lynch syndrome in a hospital-based colorectal surgery clinic

Table 4 Comparison of different features among patients with and without the microsatellite instability-high phenotype (n = 197¹) n (%)

Features	MSI-high phenotype (n = 42)	Non MSI-high phenotype (n = 155)	P
Age at diagnosis < 50 yr	18 (42.9)	29 (18.7)	0.001
Family history of colorectal cancer	15 (35.7)	45 (29.0)	0.404
Presence of Revised Bethesda criteria[16]	42 (100)	56 (36.1)	< 0.001
Presence of Amsterdam II criteria	6 (14.3)	15 (9.7)	0.391
Second primary tumors	3 (7.1)	8 (5.2)	0.620
Early stage at diagnosis	11 (26.2)	64 (41.3)	0.079

¹15 patients were excluded due to missing data on tumor histology. MSI: Microsatellite instability.