title: [Quantitative changes in the immunoglobulin G subclass system--a reliable tumor marker in squamous epithelial carcinoma in the area of the head-neck].
abstract: OBJECTIVE
  Until now no serological markers were available towards the diagnosis of squamous-cell carcinomas of the head and neck (HNSCC) particularly in the detection of posttherapeutic recurrent diseases and metastases. Previous reports described patients with malignant diseases of various tissues exhibiting a characteristic and highly significant alteration in the subclass composition of serum IgG, consisting of a reduction in %IgG1 and an increase of %IgG2. In this study we present for the first time results of this IgG-shift in patients suffering from HNSCC.
  
  
  METHODS
  A total of 111 patients was investigated at our clinic, all suffering from primary, histopathologically verified squamous cell carcinomas of the head and neck. These patients were investigated as to %Ig G1/IgG2 prior to any treatment. A second group consisted of 35 patients with local recurrences, 15 patients with distant metastases and 27 patients without tumour at the time of investigation, who were in observation for 1 to 5 years after primary treatment (T0). Thirdly, a total of 33 patients was included who were afflicted with a variety of benign diseases of the head and neck, such as chronic rhinosinusitis, chronic tonsillitis and also lateral or median cysts of the neck. Data of the three groups were compared with those of 174 healthy volunteer controls. 5 ml blood were taken from a forearm vein and the quantitation of subclasses IgG1, IgG2 and total IgG was performed by affinity chromatography. The single values obtained with all experimental groups and healthy controls showed normal distribution for primary cancer patients versus healthy control. Accordingly, significant differences between mean values were calculated with the two-sided Students t-test, and cut-off values were calculated as the arithmetic means of mean values obtained from the groups to be compared. Diagnostic sensitivities and specificities were defined as percentages of patients with %IgG1 smaller, and of healthy controls with %IgG1 greater than the cut-off value.
  
  
  RESULTS
  We found a highly significant alteration in the subclass composition of serum IgG, consisting of a reduction in %IgG1 and an increase in %IgG2 in our HNSCC groups. The present data suggest the changes in %IgG1 and %IgG2 as a useful serological tumour marker to detect primary or recurrent and/or metastatic squamous-cell carcinomas of the head and neck.
  
  
  CONCLUSIONS
  The shift in %IgG1/%IgG2 exhibited diagnostic sensitivities and specificities comparable to, or--particularly at early tumour stages--by far higher than conventional serological tumour markers. Whereas conventional serological markers directly correspond to tumourogenically derived products, the shift in %IgG1/IgG2 represents an indirect marker, consisting of a change of the host's immune system due to the presence of malignant tumours.
authors.affiliation: HNO-Univ. Klinik Graz.
authors.forename: W
authors.initials: W
authors.lastname: Anderhuber
authors.forename: W
authors.initials: W
authors.lastname: Steinschifter
authors.forename: A
authors.initials: A
authors.lastname: Gotschuli
authors.forename: E
authors.initials: E
authors.lastname: Schauenstein
authors.forename: K
authors.initials: K
authors.lastname: Schauenstein
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D009367:Neoplasm Staging; D010039:Otorhinolaryngologic Neoplasms / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D012016:Reference Values; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; D007074:Immunoglobulin G
vernacular_title: Quantitative Veränderungen im Immunglobulin G Subklassensystem--Ein verlässlicher Tumormarker bei Plattenepithelkarzinomen im Kopf-Hals-Bereich.