title: Comparison of the micronucleus and chromosome aberration techniques for the documentation of cytogenetic damage in radiochemotherapy-treated patients with rectal cancer.
abstract: OBJECTIVE
  The goal of the interdisciplinary Clinical Research Unit KFO179 (Biological Basis of Individual Tumor Response in Patients with Rectal Cancer) is to develop an individual Response and Toxicity Score for patients with locally advanced rectal cancer treated with neoadjuvant radiochemotherapy. The aim of the present study was to find a reliable and sensitive method with easy scoring criteria and high numbers of cell counts in a short period of time in order to analyze DNA damage in peripheral blood lymphocytes. Thus, the cytokinesis-block micronucleus (CBMN) assay and the chromosome aberration technique (CAT) were tested.
  
  
  METHODS
  Peripheral blood lymphocytes obtained from 22 patients with rectal cancer before (0 Gy), during (21.6 Gy), and after (50.4 Gy) radiochemotherapy were stimulated in vitro by phytohemagglutinin (PHA); the cultures were then processed for the CBMN assay and the CAT to compare the two methods.
  
  
  RESULTS
  A significant increase of chromosomal damage was observed in the course of radiochemotherapy parallel to increasing radiation doses, but independent of the chemotherapy applied. The equivalence of both methods was shown by Westlake's equivalence test.
  
  
  CONCLUSIONS
  The results show that the CBMN assay and the CAT are equivalent. For further investigations, we prefer the CBMN assay, because it is simpler through easy scoring criteria, allows high numbers of cell counts in less time, is reliable, sensitive, and has higher statistical power. In the future, we plan to integrate cytogenetic damage during radiochemotherapy into the planned Response and Toxicity Score within our interdisciplinary Clinical Research Unit.
authors.affiliation: Department of Radiotherapy and Radiooncology, University Medicine Göttingen, Göttingen, Germany.
authors.forename: Hendrik Andreas
authors.initials: HA
authors.lastname: Wolff
authors.forename: Steffen
authors.initials: S
authors.lastname: Hennies
authors.forename: Markus Karl Alfred
authors.initials: MK
authors.lastname: Herrmann
authors.forename: Margret
authors.initials: M
authors.lastname: Rave-Fränk
authors.forename: David
authors.initials: D
authors.lastname: Eickelmann
authors.forename: Patricia
authors.initials: P
authors.lastname: Virsik
authors.forename: Klaus
authors.initials: K
authors.lastname: Jung
authors.forename: Markus
authors.initials: M
authors.lastname: Schirmer
authors.forename: Michael
authors.initials: M
authors.lastname: Ghadimi
authors.forename: Clemens Friedrich
authors.initials: CF
authors.lastname: Hess
authors.forename: Robert Michael
authors.initials: RM
authors.lastname: Hermann
authors.forename: Hans
authors.initials: H
authors.lastname: Christiansen
mesh_terms: D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects* / Q000627:therapeutic use*; D002869:Chromosome Aberrations; D003131:Combined Modality Therapy; D003299:Cooperative Behavior; D048749:Cytokinesis / Q000528:radiation effects; D004249:DNA Damage; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005472:Fluorouracil / Q000009:adverse effects / Q000627:therapeutic use; D006801:Humans; D033183:Interdisciplinary Communication; D008297:Male; D015162:Micronucleus Tests; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D009944:Organoplatinum Compounds / Q000009:adverse effects; D000077150:Oxaliplatin; D011832:Radiation Injuries / Q000175:diagnosis*; D011879:Radiotherapy Dosage; D012004:Rectal Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology / Q000532:radiotherapy*
chemical_list: D009944:Organoplatinum Compounds; D000077150:Oxaliplatin; D005472:Fluorouracil