title: Influence of K-ras status and anti-tumour treatments on complications due to colorectal self-expandable metallic stents: a retrospective multicentre study.
abstract: BACKGROUND
  This study aimed to explore the relationship between K-ras status, anti-tumour treatments, and the complications of colorectal self-expandable metallic stenting in colorectal cancer.
  
  
  METHODS
  This is a retrospective, multicentre study of 91 patients with obstructive advanced colorectal cancer palliated with enteral stents between 2007 and 2011.
  
  
  RESULTS
  K-ras wild-type tumours were diagnosed in 44 patients (48.4%); 82 (90.1%) received chemotherapy and 45 (49.4%) had additional biological therapy (34 bevacizumab, 11 cetuximab). Twenty-one (23.1%) experienced stent-related complications: 11 (52.4%) occurred in the K-ras mutant group (P=0.9). K-ras wild-type patients were not less likely to develop adverse events than K-ras mutant patients (OR, 0.99; 95% CI: 0.4-2.7). Overall mean time to complication was 167.6 days (range 4-720 days), with no difference between the two groups (141 vs. 197 days; P=0.5). Chemotherapy did not influence the risk of complications (OR, 0.56; 95% CI: 0.14-2.9), and there was no evidence that patients treated with chemotherapy and cetuximab were more likely to experience stent-related complications than patients treated with chemotherapy alone, or untreated (OR, 1.2; 95% CI: 0.2-5.9). Although perforation rates were higher with bevacizumab-based treatment (11.8% vs. 7%), this result was not statistically significant (P=0.69).
  
  
  CONCLUSIONS
  K-ras mutation status, chemotherapy, and biological treatments should not influence colorectal stent-related complication rates.
authors.affiliation: Gastroenterology Unit, S.Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy. Electronic address: lorenzofuccio@gmail.com.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Fuccio
authors.affiliation: Im3D Medical Imaging Lab, Turin, Italy.
authors.forename: Loredana
authors.initials: L
authors.lastname: Correale
authors.affiliation: Department of Surgical Sciences, University of Turin, Turin, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Arezzo
authors.affiliation: Digestive Endoscopy Unit, Istituto Clinico Humanitas, Rozzano, Milan, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Repici
authors.affiliation: Department of Gastroenterology, University Hospital L. Sacco, Milan, Italy.
authors.forename: Gianpiero
authors.initials: G
authors.lastname: Manes
authors.affiliation: Endoscopy Division, European Institute of Oncology, Milan, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Trovato
authors.affiliation: Gastrointestinal Endoscopy Unit, Azienda Ospedaliera San Paolo, University of Milan, Milan, Italy.
authors.forename: Benedetto
authors.initials: B
authors.lastname: Mangiavillano
authors.affiliation: Gastroenterology and Endoscopy Unit, New S. Agostino Hospital, Modena, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Manno
authors.affiliation: Division of Gastroenterology, Varese, Italy.
authors.forename: Claudio Camillo
authors.initials: CC
authors.lastname: Cortelezzi
authors.affiliation: Department of Surgery, University of Milano-Bicocca, San Gerardo Hospital, Monza, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Dinelli
authors.affiliation: Unit of Digestive Endoscopy, Department of Surgery, AUSL Bologna Bellaria-Maggiore Hospital, Bologna, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Cennamo
authors.affiliation: Endoscopy Unit, National Cancer Institute and G. Pascale Foundation, Naples, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: de Bellis
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage / Q000009:adverse effects; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D000068258:Bevacizumab; D000068818:Cetuximab; D015179:Colorectal Neoplasms / Q000150:complications / Q000235:genetics* / Q000628:therapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007415:Intestinal Obstruction / Q000209:etiology / Q000628:therapy*; D007416:Intestinal Perforation / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010166:Palliative Care; D011475:Prosthesis Failure / Q000209:etiology; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D012189:Retrospective Studies; D015607:Stents / Q000009:adverse effects*; D015996:Survival Rate; D013997:Time Factors; D018631:ras Proteins / Q000235:genetics*
chemical_list: D061067:Antibodies, Monoclonal, Humanized; C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D000068258:Bevacizumab; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins; D000068818:Cetuximab
keywords: Bevacizumab; Cetuximab; Colorectal cancer; K-ras mutation status; Occlusion; Self-expandable metal stent