KRAS and mucinous cystadenocarcinoma: Another point in favor of adjuvant treatment is evidence that primary retroperitoneal mucinous cystadenocarcinomas and ovarian mucinous tumor have similar mechanisms in their histogenesis; this was reported by Tenti et al. [11], who had found K-ras oncogene mutation at codon 12 and demonstrated immunoreactivity for intestinal cell markers.