TY - JOUR
T1 - DBCG-IMN
T2 - A Population-Based Cohort Study on the Effect of Internal Mammary Node Irradiation in Early Node-Positive Breast Cancer
AU - Thorsen, Lise Bech Jellesmark
AU - Offersen, Birgitte Vrou
AU - Danø, Hella
AU - Berg, Martin
AU - Jensen, Ingelise
AU - Pedersen, Anders Navrsted
AU - Zimmermann, Sune Jürg
AU - Brodersen, Hans-Jürgen
AU - Overgaard, Marie
AU - Overgaard, Jens
N1 - © 2015 by American Society of Clinical Oncology.
PY - 2016
Y1 - 2016
N2 - PURPOSE: It is unknown whether irradiation of the internal mammary lymph nodes improves survival in patients with early-stage breast cancer. A possible survival benefit might be offset by radiation-induced heart disease. We assessed the effect of internal mammary node irradiation (IMNI) in patients with early-stage node-positive breast cancer.PATIENTS AND METHODS: In this nationwide, prospective population-based cohort study, we included patients who underwent operation for unilateral early-stage node-positive breast cancer. Patients with right-sided disease were allocated to IMNI, whereas patients with left-sided disease were allocated to no IMNI because of the risk of radiation-induced heart disease. The primary end point was overall survival. Secondary end points were breast cancer mortality and distant recurrence. Analyses were by intention to treat.RESULTS: A total of 3,089 patients were included. Of these, 1,492 patients were allocated to IMNI, whereas 1,597 patients were allocated to no IMNI. With a median of 8.9 years of follow-up time, the 8-year overall survival rates were 75.9% with IMNI versus 72.2% without IMNI. The adjusted hazard ratio (HR) for death was 0.82 (95% CI, 0.72 to 0.94; P = .005). Breast cancer mortality was 20.9% with IMNI versus 23.4% without IMNI (adjusted HR, 0.85; 95% CI, 0.73 to 0.98; P = .03). The risk of distant recurrence at 8 years was 27.4% with IMNI versus 29.7% without IMNI (adjusted HR, 0.89; 95% CI, 0.78 to 1.01; P = .07). The effect of IMNI was more pronounced in patients at high risk of internal mammary node metastasis. Equal numbers in each group died of ischemic heart disease.CONCLUSION: In this naturally allocated, population-based cohort study, IMNI increased overall survival in patients with early-stage node-positive breast cancer.
AB - PURPOSE: It is unknown whether irradiation of the internal mammary lymph nodes improves survival in patients with early-stage breast cancer. A possible survival benefit might be offset by radiation-induced heart disease. We assessed the effect of internal mammary node irradiation (IMNI) in patients with early-stage node-positive breast cancer.PATIENTS AND METHODS: In this nationwide, prospective population-based cohort study, we included patients who underwent operation for unilateral early-stage node-positive breast cancer. Patients with right-sided disease were allocated to IMNI, whereas patients with left-sided disease were allocated to no IMNI because of the risk of radiation-induced heart disease. The primary end point was overall survival. Secondary end points were breast cancer mortality and distant recurrence. Analyses were by intention to treat.RESULTS: A total of 3,089 patients were included. Of these, 1,492 patients were allocated to IMNI, whereas 1,597 patients were allocated to no IMNI. With a median of 8.9 years of follow-up time, the 8-year overall survival rates were 75.9% with IMNI versus 72.2% without IMNI. The adjusted hazard ratio (HR) for death was 0.82 (95% CI, 0.72 to 0.94; P = .005). Breast cancer mortality was 20.9% with IMNI versus 23.4% without IMNI (adjusted HR, 0.85; 95% CI, 0.73 to 0.98; P = .03). The risk of distant recurrence at 8 years was 27.4% with IMNI versus 29.7% without IMNI (adjusted HR, 0.89; 95% CI, 0.78 to 1.01; P = .07). The effect of IMNI was more pronounced in patients at high risk of internal mammary node metastasis. Equal numbers in each group died of ischemic heart disease.CONCLUSION: In this naturally allocated, population-based cohort study, IMNI increased overall survival in patients with early-stage node-positive breast cancer.
U2 - 10.1200/JCO.2015.63.6456
DO - 10.1200/JCO.2015.63.6456
M3 - Journal article
C2 - 26598752
SN - 0732-183X
VL - 34
SP - 314
EP - 320
JO - Journal of clinical oncology : official journal of the American Society of Clinical Oncology
JF - Journal of clinical oncology : official journal of the American Society of Clinical Oncology
IS - 4
ER -