title: Effects of Curative Colorectal Cancer Surgery on Exhaled Volatile Organic Compounds and Potential Implications in Clinical Follow-up.
abstract: OBJECTIVE
  The aim of this study was to determine whether the volatile organic compounds (VOCs) pattern in colorectal cancer (CRC) patients is modified by curative surgery for a potential application in the oncologic follow-up.
  
  
  BACKGROUND
  CRC has been proved to induce metabolic derangements detectable by high through-output techniques in exhaled breath showing a specific pattern of VOCs.
  
  
  METHODS
  Forty-eight CRC patients and 55 healthy controls (HC) entered the study. Thirty-two patients (M/F: 1.4; mean age 63 years) attended the oncologic follow-up (mean 24 months) and were found disease-free. Breath samples were collected under similar environmental conditions into a Tedlar bags and processed offline by thermal-desorption gas chromatography-mass spectrometry (TD-GC-MS). VOCs were selected by U test to build a Probabilistic Neural Network (PNN) model to set-up a training phase, which was cross-validated using the leave-one out method.
  
  
  RESULTS
  A total of 11 VOCs were finally selected for their excellent discriminant performance in identifying disease-free patients in follow-up from CRC patients before surgery, (sensitivity 100%, specificity 97.92%, accuracy 98.75%, and AUC: 1). The same VOCs pattern discriminated follow-up patients from HC, with a sensitivity of 100%, specificity of 90.91%, accuracy of 94.25%, and AUC 0.959.
  
  
  CONCLUSIONS
  Exhaled VOCs pattern from CRC patients is modified by cancer removal confirming the tight relationship between tumor metabolism and exhaled VOCs. PNN analysis provides a high discriminatory tool to identify patients disease-free after curative surgery suggesting potential implications in CRC screening and secondary prevention.
authors.affiliation: *Department of Emergency and Organ Transplantation, Azienda Ospedaliero-Universitaria, Bari, Italy †Department of Chemistry, University Aldo Moro of Bari, Bari, Italy.
authors.forename: Donato F
authors.initials: DF
authors.lastname: Altomare
authors.forename: Maria
authors.initials: M
authors.lastname: Di Lena
authors.forename: Francesca
authors.initials: F
authors.lastname: Porcelli
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Travaglio
authors.forename: Francesco
authors.initials: F
authors.lastname: Longobardi
authors.forename: Maria
authors.initials: M
authors.lastname: Tutino
authors.forename: Norma
authors.initials: N
authors.lastname: Depalma
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Tedesco
authors.forename: Annamaria
authors.initials: A
authors.lastname: Sardaro
authors.forename: Riccardo
authors.initials: R
authors.lastname: Memeo
authors.forename: Gianluigi
authors.initials: G
authors.lastname: de Gennaro
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D001944:Breath Tests; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000378:metabolism; D055088:Early Detection of Cancer; D045853:Exhalation; D005260:Female; D005500:Follow-Up Studies; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D055549:Volatile Organic Compounds / Q000032:analysis*
chemical_list: D014408:Biomarkers, Tumor; D055549:Volatile Organic Compounds