title: KRAS Mutation Status Is Not a Predictor for Tumor Response and Survival in Rectal Cancer Patients Who Received Preoperative Radiotherapy With 5-Fluoropyrimidine Followed by Curative Surgery.
abstract: We evaluated the tumor response and survival according to the KRAS oncogene status in locally advanced rectal cancer. One hundred patients with locally advanced rectal cancer (cT3-4N0-2M0) received preoperative radiation of 50.4 Gy in 28 fractions with 5-fluorouracil and total mesorectal excision. Tumor DNA from each patient was obtained from pretreatment biopsy tissues. A Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation was found in 26 (26%) of the 100 patients. Downstaging (ypT0-2N0M0) rates after preoperative chemoradiotheray were not statistically different between the wild-type and mutant-type KRAS groups (30.8% vs 27.0%, P = 0.715, respectively). After a median follow-up time of 34 months, there was no statistically significant difference in the 3-year relapse-free survival (82.2% vs 82.6%, P = 0.512) and overall survival (94.7% vs 92.3%, P = 0.249) rates between wild-type and mutant-type KRAS groups, respectively. The KRAS mutation status does not influence the tumor response to the radiotherapy and survival in locally advanced rectal cancer patients who received preoperative chemoradiotherapy and curative surgery.
authors.affiliation: From the Department of Radiation Oncology, Seoul St. Mary's Hospital (JWL, HSJ); Department of Radiation Oncology (JHL, SHK, MJC); Department of Medical Oncology (BYS); Department of Colorectal Surgery, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea (B-HK, HJK, HMC).
authors.forename: Jeong Won
authors.initials: JW
authors.lastname: Lee
authors.forename: Jong Hoon
authors.initials: JH
authors.lastname: Lee
authors.forename: Byoung Yong
authors.initials: BY
authors.lastname: Shim
authors.forename: Sung Hwan
authors.initials: SH
authors.lastname: Kim
authors.forename: Mi-Joo
authors.initials: MJ
authors.lastname: Chung
authors.forename: Bong-Hyeon
authors.initials: BH
authors.lastname: Kye
authors.forename: Hyung Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Hyeon Min
authors.initials: HM
authors.lastname: Cho
authors.forename: Hong Seok
authors.initials: HS
authors.lastname: Jang
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000401:mortality / Q000628:therapy*; D000368:Aged; D059186:Chemoradiotherapy, Adjuvant; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D011743:Pyrimidines / Q000627:therapeutic use; D012004:Rectal Neoplasms / Q000235:genetics* / Q000401:mortality / Q000628:therapy*; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome; D018631:ras Proteins / Q000235:genetics*
chemical_list: C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D011743:Pyrimidines; C029269:5-fluoropyrimidine; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins