KRAS and colorectal carcinoma: A confounding factor to assessing the functional role of PTEN mutations in prognosis is the changing landscape of treatments for CRC over the past two decades, with initial dependence on cytotoxic chemotherapies augmented with use of antibodies targeting EGFR (typically for tumors lacking strongly activating KRAS mutations) regorafenib, and tiparacil/trifluidine.