Correlation betwen MKK4 expression (exp) and clinicopathological features, KRAS/NRAS mutation in metastatic colorectal cancer (mCRC).

Abstract

e14500 Background: We aimed to evaluate correlation between MKK4 exp & clinicopathological features in mCRC Methods: MKK4 exp was assessed by immunoreactive score (IRS). Staining intensity [0 (no), 1+ (weak), 2+ (moderate), 3+ (strong)] & % of positively stained cells [0 (0%), 1( < 10%), 2 (11-50%), 3 (51-80%), 4 ( > 80%)]. IRS was calculated by this formula (IRS = SI × PP). Cut-offs were explored with ROC analysis. AUC was 0.629 (95%CI:0.419-0.840) & best cut-off value for MKK4 was 2.5 (sensitivity of 68 %). Groups were WIR ('weak'; IRS:0-2) & SIR ('strong'; IRS ≥3). Results: We enrolled 95 patients. Median follow-up was 31.4 months. MKK4 exp strength outcomes are shown in table. K-ras/N-ras mutation rate was 45.2%. WIR patients had longer OS (p: 0.03). In WIR group, metastatic ones at diagnosis had shorter DFS (p:0,05). There was no PFS difference (p: 0,15). In correlation analysis, there was a a negative correlation between MKK4 expression & 1st line treatment resistance, k-ras/n-ras mt, OS, PFS, DFS (r: -0.01; r: -0,06; -0,02; -0,10; -0,06; -0,34) ( p:0,04 for DFS). Conclusions: MKK4 exp inversely correlates with survival outcomes & ras mutation. WIR leads longer DFS & OS. [Table: see text]