Table 1.

Clinical trials investigating the impact of antidiabetic therapy in T2DM patients on CRC risk or survival of patients with CRC.

Publication	Antidiabetic Therapy	N of Patients	Follow-Up	Results
Schiel et al. (2005) [194]	Insulin	147 patients with T2DM114 patients with T1DM	10 years	Increased incidence of colon and rectum cancer.
Home et al. (2010) [190] ADOPT trial	Metformin Rosiglitazone Glyburide	1454 patients with T2DM on metformin 1456 patients with T2DM on rosiglitazone 1441 patients with T2DM on glyburide	4 years	Number of patients who developed CRC in glyburide group was higher than in metformin and rosiglitazone groups. No obvious advantage of metformin or rosiglitazone.
Home et al. (2010) [190] RECORD trial	Sulfonylurea Metformin Rosiglitazone	1122 patients with T2DM on sulfonylurea and added metformin 1103 patients with T2DM on sulfonylurea and added rosiglitazone 1105 patients with T2DM on metformin and added sulfonylurea 1117 patients with T2DM on metformin and added rosiglitazone	5.5 years	Number of patients who developed gastrointestinal cancers was higher in the groups receiving sulfonylurea as background or add-on therapy.
Nauck et al. (2018) [191]	Liraglutide	4668 patients with T2DM on liraglutide 4672 patients with T2DM on placebo	3.8 years	No difference in colon or rectum cancer incidence in liraglutide and placebo group.
Singh et al. (2016) [192]	Metformin	115 patients with CRC and T2DM on adjuvant chemotherapy and metformin 152 patients with CRC and T2DM on adjuvant chemotherapy without use of metformin	6.5 years	No difference in disease-free survival, overall survival and time to recurrence between patients on metformin and without use of metformin.
Vernieri et al. (2019) [193]	Metformin	76 patients with CRC and T2DM on adjuvant chemotherapy and metformin 44 patients with CRC and T2DM on adjuvant chemotherapy without use of metformin	60.4 months	No difference in overall survival and relapse-free survival between patients on metformin and without use of metformin