Frequency and coexistence of KRAS, NRAS, BRAF and PIK3CA mutations and occurrence of MMR deficiency in Danish colorectal cancer patients - Poulsen, T S; de Oliveira, D VNP; Espersen, M LM; Klarskov, L L; Skovrider-Ruminski, W; Hogdall, E (APMIS, 2021)