Introduction: Colorectal cancer (CRC) is the second most common cause of cancer-related deaths. The hippo pathway works as a regulator of organ growth and is often a target for mutations in cancer. Ferm domain containing protein 6 (FRMD6) is an activator of the hippo pathway. This study aimed to explore the role of FRMD6 in CRC and to determine how well it works as a prognostic factor among CRC patients.

Methods: The tumor expression of FRMD6 was evaluated using immunohistochemistry in 538 colorectal patients operated on at Helsinki University Hospital. We assessed FRMD6 expression with clinicopathological parameters and the impact of FRMD6 expression on survival.

Results: Patients with a high FRMD6 expression exhibited a better prognosis (univariable hazard ratio [HR] 0.58, 95% confidence interval [CI] 0.41-0.81), with a 5-year disease-specific survival (DSS) of 66.3%. By contrast, patients with a low FRMD6 expression had a 5-year DSS of 52.8%. A high FRMD6 expression level served as an independent predictor for better survival in the Cox multivariable survival analysis (HR 0.53, 95% CI 0.33-0.86).

Discussion: To our knowledge, this is the first study to show that a high FRMD6 expression is an independent marker for a better prognosis in CRC and could help determine the prognosis for CRC patients.