gms | German Medical Science

MAINZ//2011: 56. GMDS-Jahrestagung und 6. DGEpi-Jahrestagung

Deutsche Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie e. V.
Deutsche Gesellschaft für Epidemiologie e. V.

26. - 29.09.2011 in Mainz

Radiotherapy-induced late adverse effects of tissue in breast cancer patients – results from the German MARIE(RAD) study

Meeting Abstract

  • Petra Seibold - Deutsches Krebsforschungszentrum, Heidelberg
  • Irmgard Helmbold - Deutsches Krebsforschungszentrum, Heidelberg
  • Peter Schmezer - Deutsches Krebsforschungszentrum, Heidelberg
  • Rainer Claus - Deutsches Krebsforschungszentrum, Heidelberg
  • Johannes Claßen - St. Vincentius-Kliniken, Karlsruhe, Karlsruhe
  • Angela Hoederath - SLK Kliniken, Heilbronn, Heilbronn
  • Thomas Schnabel - Klinikum der Stadt Ludwigshafen, Ludwigshafen
  • Odilia Popanda - Deutsches Krebsforschungszentrum, Heidelberg
  • Jenny Chang-Claude - Deutsches Krebsforschungszentrum, Heidelberg

Mainz//2011. 56. Jahrestagung der Deutschen Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie (gmds), 6. Jahrestagung der Deutschen Gesellschaft für Epidemiologie (DGEpi). Mainz, 26.-29.09.2011. Düsseldorf: German Medical Science GMS Publishing House; 2011. Doc11gmds225

DOI: 10.3205/11gmds225, URN: urn:nbn:de:0183-11gmds2254

Veröffentlicht: 20. September 2011

© 2011 Seibold et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielfältigt, verbreitet und öffentlich zugänglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

Text

Background: Radiotherapy (RT) is routinely applied after breast conserving surgery (BCS) in breast cancer patients to decrease the risk of local recurrences. However, late adverse effects of tissue such as skin alterations (e.g. telangiectasia) and fibrosis can occur as a consequence of radiotherapy years after treatment. We investigated the influence of potential risk factors such as radiation dose, BMI, and genetic variants on the occurrence of RT-induced late adverse effects.

Methods: A subgroup of 414 breast cancer patients from the study region Rhein-Neckar-Karlsruhe of the German MARIE study, who underwent RT after BCS between 2002 and 2005 but did not receive chemotherapy, participated in this subproject (participation rate: 84%). Exclusion criteria were bilateral disease, previous cancer(s) or metastases at time of diagnosis. The occurrence of late adverse effects was evaluated by an experienced study physician according to standardized EORTC/RTOG scoring, ranging from 0=no late toxicities to 4=severe adverse effects. The non-irradiated breast was used as reference. Associations of risk factors with skin alterations and with fibrosis, respectively, were assessed by logistic regression in 387 patients, excluding individuals who received intraoperative or interstitial boost to achieve a homogeneously exposed population. Genotype association was tested in up to 363 individuals with genotype information. An independent study of 390 breast cancer patients from the same study region (RT after BCS: 1998-2001) was used for replication (iPlex application).

Results: A total of 46 of 414 patients (11%) presented with skin alterations grade 2 or 3 after a median follow-up time of 67 months. 43 patients developed fibrosis (10%), of whom 23 experienced skin alterations as well. No grade 4 toxicities occurred. In a model adjusted for age at end of RT, follow-up time, and normalized total radiation dose, BMI (25+ vs. <25: OR 2.4, 95% CI 1.1-5.4) and boost energy type (p<0.001) were significantly associated with skin alterations. Two SNPs in the oxidative stress-related gene NQO1 were found to decrease the risk for telangiectasia (OR 0.3, 95% 0.1-0.9). This finding was replicated in an independent study. Risk for developing fibrosis was significantly associated with heavy smoking (≥ 20 pack years) (OR 3.97, 95% CI 1.2-13.6) and non-significantly with hypertension (OR 2.2, 95% CI 0.9-5.0).

Conclusion: We confirmed previous findings that, in addition to therapy-related factors, modifiable patient-related factors may alter the risk for late adverse effects and identified possible modifying genetic variants.