title: DEGRO practical guidelines: radiotherapy of breast cancer III--radiotherapy of the lymphatic pathways.
abstract: OBJECTIVE
  The purpose of this work is to update the practical guidelines for adjuvant radiotherapy of the regional lymphatics of breast cancer published in 2008 by the breast cancer expert panel of the German Society of Radiation Oncology (DEGRO).
  
  
  METHODS
  A comprehensive survey of the literature concerning regional nodal irradiation (RNI) was performed using the following search terms: "breast cancer", "radiotherapy", "regional node irradiation". Recent randomized trials were analyzed for outcome as well as for differences in target definition. Field arrangements in the different studies were reproduced and superimposed on CT slices with individually contoured node areas. Moreover, data from recently published meta-analyses and guidelines of international breast cancer societies, yielding new aspects compared to 2008, provided the basis for defining recommendations according to the criteria of evidence-based medicine. In addition to the more general statements of the German interdisciplinary S3 guidelines updated in 2012, this paper addresses indications, targeting, and techniques of radiotherapy of the lymphatic pathways after surgery for breast cancer.
  
  
  RESULTS
  International guidelines reveal substantial differences regarding indications for RNI. Patients with 1-3 positive nodes seem to profit from RNI compared to whole breast (WBI) or chest wall irradiation alone, both with regard to locoregional control and disease-free survival. Irradiation of the regional lymphatics including axillary, supraclavicular, and internal mammary nodes provided a small but significant survival benefit in recent randomized trials and one meta-analysis. Lymph node irradiation yields comparable tumor control in comparison to axillary lymph node dissection (ALND), while reducing the rate of lymph edema. Data concerning the impact of 1-2 macroscopically affected sentinel node (SN) or microscopic metastases on prognosis are conflicting.
  
  
  CONCLUSIONS
  Recent data suggest that the current restrictive use of RNI should be scrutinized because the risk-benefit relationship appears to shift towards an improvement of outcome.
authors.affiliation: Klinik für Radioonkologie und Strahlentherapie, Städtisches Klinikum Karlsruhe, Karlsruhe, Germany, marie-luise.sautter-bihl@klinikum-karlsruhe.de.
authors.forename: M-L
authors.initials: ML
authors.lastname: Sautter-Bihl
authors.forename: F
authors.initials: F
authors.lastname: Sedlmayer
authors.forename: W
authors.initials: W
authors.lastname: Budach
authors.forename: J
authors.initials: J
authors.lastname: Dunst
authors.forename: P
authors.initials: P
authors.lastname: Feyer
authors.forename: R
authors.initials: R
authors.lastname: Fietkau
authors.forename: C
authors.initials: C
authors.lastname: Fussl
authors.forename: W
authors.initials: W
authors.lastname: Haase
authors.forename: W
authors.initials: W
authors.lastname: Harms
authors.forename: M D
authors.initials: MD
authors.lastname: Piroth
authors.forename: R
authors.initials: R
authors.lastname: Souchon
authors.forename: F
authors.initials: F
authors.lastname: Wenz
authors.forename: R
authors.initials: R
authors.lastname: Sauer
mesh_terms: D001943:Breast Neoplasms / Q000532:radiotherapy*; D002277:Carcinoma / Q000532:radiotherapy* / Q000556:secondary*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000528:radiation effects*; D008207:Lymphatic Metastasis; D018787:Radiation Oncology / Q000592:standards*; D011879:Radiotherapy Dosage; D020266:Radiotherapy, Conformal / Q000592:standards*