title: Diagnostic and prognostic value of SHOX2 and SEPT9 DNA methylation and cytology in benign, paramalignant, and malignant ascites.
abstract: BACKGROUND
  Cytology remains the gold standard for the detection of malignant cells in ascites. However, its sensitivity is limited. The aim of this study was to evaluate DNA methylation biomarkers for the differential diagnosis of benign (ascites in patients without malignancy), malignant (ascites in cancer patients directly caused by malignancy), and paramalignant (ascites in cancer patients caused by comorbidities but not by malignancy) ascites.
  
  
  METHODS
  A cohort of 283 patients (134 cancer patients, 149 patients with benign diseases) presenting with ascites was prospectively enrolled. Ascites was evaluated by means of cytopathological investigation and DNA methylation of SHOX2 and SEPT9 in the cell-free and cellular fraction. DNA methylation in bisulfite-converted DNA was determined using quantitative methylation specific real-time PCR. Cytopathological and DNA methylation results were evaluated with regard to diagnosis and overall survival (OS).
  
  
  RESULTS
  Patients with positive DNA methylation had a poor overall survival compared to methylation-negative patients (hazard ratio: HR = 1.97, p = 0.001). In multivariate survival analysis, DNA methylation was an independent prognostic parameter (p = 0.003) together with age (HR = 1.03, p < 0.001) and the presence of malignant disease (HR = 1.87, p < 0.001). The combination of methylation with cytopathological analyses led to a 42 % increase in the detection rate of malignant ascites, resulting in 37 % positively diagnosed cancer patients and a specificity of 97 %. Among cancer patients, patients with DNA methylation-positive ascites showed an adverse clinical course (HR = 1.63, p = 0.039).
  
  
  CONCLUSIONS
  DNA methylation testing adds diagnostic and prognostic information and might constitute an effective ancillary method for the differential diagnosis of malignant, paramalignant, and benign ascites.
authors.affiliation: Institute of Pathology, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.
authors.forename: Maria
authors.initials: M
authors.lastname: Jung
authors.affiliation: Institute of Pathology, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.
authors.forename: Svenja
authors.initials: S
authors.lastname: Pützer
authors.affiliation: Institute of Pathology, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.
authors.forename: Heidrun
authors.initials: H
authors.lastname: Gevensleben
authors.affiliation: Institute of Pathology, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Meller
authors.affiliation: Institute of Pathology, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.
authors.forename: Glen
authors.initials: G
authors.lastname: Kristiansen
authors.affiliation: Institute of Pathology, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.|Department of Otolaryngology, Head and Neck Surgery, University Hospital Bonn, Bonn, Germany.
authors.forename: Dimo
authors.initials: D
authors.lastname: Dietrich
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001201:Ascites / Q000175:diagnosis* / Q000209:etiology / Q000235:genetics / Q000401:mortality / Q000473:pathology; D019175:DNA Methylation / Q000235:genetics*; D003937:Diagnosis, Differential; D005260:Female; D018398:Homeodomain Proteins / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications / Q000235:genetics / Q000401:mortality / Q000473:pathology; D011379:Prognosis; D011446:Prospective Studies; D060888:Real-Time Polymerase Chain Reaction; D058112:Septins / Q000235:genetics*; D016019:Survival Analysis; D055815:Young Adult
chemical_list: D018398:Homeodomain Proteins; C484664:SHOX2 protein, human; C474315:SEPTIN9 protein, human; D058112:Septins
keywords: Ascites; Biomarkers; Cancer diagnosis; Cell-free DNA; Cytology; DNA methylation; Liquid biopsy; SEPT9; SHOX2