title: Serum antibodies against Saccharomyces cerevisiae: a new prognostic indicator in metastatic renal-cell carcinoma.
abstract: OBJECTIVE
  A recent study reported that a diet rich in bread and refined cereals might have an unfavorable role in the development of renal cell carcinoma (RCC). To test whether an underlying intolerance of bread ingredients is responsible for the unfavorable influence of bread on RCC, we examined patient sera for the presence of food-specific IgG.
  
  
  METHODS
  A commercial test was used to detect food-specific IgG directed against a panel of 113 food antigens in sera of 54 patients with metastatic RCC. Kaplan-Meier estimates were used for univariate survival analysis, and differences in survival curves were assessed with the log-rank test. Multivariate survival analysis was done using a Cox regression model.
  
  
  RESULTS
  We found that RCC patients with elevated serum levels of IgG antibodies against S. cerevisiae, commonly known as baker's yeast and yet another bread component, have an unfavorable clinical course. Median survival of patients with high levels of S. cerevisiae IgG was only 17.8 months, whereas median survival of patients with low S. cerevisiae IgG was 43.8 months (P = 0.0022; log-rank). Multivariate survival analysis identified high levels of S. cerevisiae IgG as a strong and independent prognostic risk factor (risk ratio 4.6, P = 0.001; 95% CI 1.61-13.08).
  
  
  CONCLUSIONS
  Our findings indicate that serum levels of IgG against S. cerevisiae may predict survival in patients with metastatic RCC. The data suggest not cereals but baker's yeast being the critical component of bread that may cause immune deviation and impaired immunosurveillance in predisposed RCC patients.
authors.affiliation: Immunotherapy Unit, Department of Urology, Innsbruck Medical University, Innrain 66a, 6020, Innsbruck, Austria.
authors.forename: Reinhold
authors.initials: R
authors.lastname: Ramoner
authors.forename: Andrea
authors.initials: A
authors.lastname: Rahm
authors.forename: Hubert
authors.initials: H
authors.lastname: Gander
authors.forename: Björn
authors.initials: B
authors.lastname: Stollenwerk
authors.forename: Claudia
authors.initials: C
authors.lastname: Falkensammer
authors.forename: Nicolai
authors.initials: N
authors.lastname: Leonhartsberger
authors.forename: Martin
authors.initials: M
authors.lastname: Thurnher
mesh_terms: D000328:Adult; D002292:Carcinoma, Renal Cell / Q000097:blood* / Q000556:secondary / Q000628:therapy; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007167:Immunotherapy; D007680:Kidney Neoplasms / Q000097:blood* / Q000556:secondary / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012441:Saccharomyces cerevisiae / Q000276:immunology*; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D007074:Immunoglobulin G