ESR1 and invasive breast carcinoma: Detectable prostein expression was linked to high grade (p = 0.0105), HER2 positivity (p = 0.0312), and estrogen receptor negativity (p = 0.0330) in invasive breast carcinomas of no special type (NST), V0 status (p = 0.0139), right sided tumor location (p = 0.0479), and KRAS mutations (p = 0.0133) in colorectal cancer, pN0 stage (p = 0.0424) in pancreatic ductal adenocarcinoma as well as to microsatellite instability in gastric cancers (p = 0.0015).