@article{3126649,
    title = "KRAS Mutation Status Dictates Optimal Surgical Margin Width in Patients Undergoing Resection of Colorectal Liver Metastases",
    author = "Margonis, G.A. and Sasaki, K. and Andreatos, N. and Kim, Y. and Merath, K. and Wagner, D. and Wilson, A. and Buettner, S. and Amini, N. and Antoniou, E. and Pawlik, T.M.",
    journal = "Annals of Surgical Oncology",
    year = "2017",
    volume = "24",
    number = "1",
    pages = "264-271",
    publisher = "Springer New York LLC",
    issn = "1068-9265, 1534-4681",
    doi = "10.1245/s10434-016-5609-1",
    keywords = "fluorouracil;  irinotecan;  oxaliplatin;  KRAS protein, human;  protein p21, adult;  Article;  cancer chemotherapy;  cancer patient;  cancer surgery;  colorectal liver metastasis;  female;  gene mutation;  human;  liver resection;  major clinical study;  male;  oncogene K ras;  outcome assessment;  overall survival;  post treatment survival;  surgical margin;  aged;  colorectal tumor;  genetics;  liver resection;  liver tumor;  middle aged;  mutation;  pathology;  prognosis;  secondary;  surgical margin;  survival rate, Aged;  Colorectal Neoplasms;  Female;  Hepatectomy;  Humans;  Liver Neoplasms;  Male;  Margins of Excision;  Middle Aged;  Mutation;  Prognosis;  Proto-Oncogene Proteins p21(ras);  Survival Rate",
    abstract = "Background: The optimal tumor-free margin width remains controversial and may be inappropriate to investigate without considering differences in the underlying tumor biology. Methods: R1 resection was defined as margin clearance less than 1 mm. R0 resection was further divided into 3 groups: 1–4, 5–9, and ≥10 mm. The impact of margin width on overall survival (OS) relative to KRAS status [wild type (wtKRAS) vs. mutated (mutKRAS)] was assessed. Results: A total of 411 patients met inclusion criteria. Median patient age was 58 years (interquartile range, 49.7–66.7); most patients were male (n = 250; 60.8 %). With a median follow-up of 28.3 months, median and 5-year OS were 69.8 months and 55.1 %. Among patients with wtKRAS tumors, although margin clearance of 1–4 mm or more was associated with improved OS compared to R1 (all P < 0.05), no difference in OS was observed when comparing margin clearance of 1–4 mm to the 5–9 mm and the ≥10 mm groups (all P > 0.05). In contrast, among patients with mutKRAS tumors, all three groups of margin clearance (1–4, 5–9, and ≥10 mm) fared no better in terms of 5-year survival compared to R1 resection (all P > 0.05). Conclusions: While a 1–4 mm margin clearance in patients with wtKRAS tumors was associated with improved survival, wider resection width did not confer an additional survival benefit. In contrast, margin status—including a 1 cm margin—did not improve survival among patients with mutKRAS tumors. © 2016, Society of Surgical Oncology."
}