The Interplay of Primary Tumor Location and KRAS Mutation Status in Patients with Synchronous Colorectal Cancer Liver Metastases: Current Data and Unanswered Questions

Excerpt

Primary tumor location (PTL) and KRAS mutation status are gradually gaining acceptance as useful surrogates of tumor biology and have an evolving role in the prognostication of patients who undergo hepatectomy for colorectal cancer liver metastases (CRLM). Although the association of each of these factors with prognosis has been repeatedly assessed, data on their interplay are far more limited, rendering the present work pertinent.1 The authors first analyzed survival outcomes according to PTL [right-sided (RS) vs. left-sided (LS)] and KRAS mutation status [mutant KRAS (mutKRAS) vs. wild-type KRAS (wtKRAS)] among 227 patients who underwent resection for synchronous CRLM between 2006 and 2015 at the Severance Hospital in Seoul; subsequently, the outcomes of patients belonging to the 4 subgroups defined by the combination of PTL and KRAS mutation status (namely RS/mutKRAS, RS/wtKRAS, LS/mutKRAS and LS/wtKRAS) were independently considered.1 To our knowledge, this is the first study to examine the interplay of these factors in patients with synchronous CRLM who are traditionally thought to exhibit a more aggressive disease course compared to patients with metachronous tumors.2 However, given the lack of definitive proof that synchronous and metachronous disease are really distinct entities, it would perhaps have been more interesting to assess both of these subgroups simultaneously. …