Regional Nodal Irradiation in Early-Stage Breast Cancer

In the European Organization for Research and Treatment of Cancer (EORTC) trial reported by Poortmans et al. (July 23 issue), 1there was no improvement in overall survival at 10 years among patients who underwent internal mammary and medial supraclavicular lymphnode irradiation (regional nodal irradiation), as compared with patients who did not undergo regional nodal radiation (82.3% vs. 80.7%, P = 0.06).Poortmans et al. report that analyses at 15 years and 20 years are planned.Nevertheless, distant disease-free survival was improved among patients who underwent regional nodal irradiation, as compared with patients who did not undergo regional nodal irradiation (78% vs. 75%, P = 0.02).The NCIC Clinical Trials Group MA.20 trial reported by Whelan et al. 2 in the same issue of the Journal showed a similar improvement in distant disease-free survival at 10 years (86.3% in the nodal-irradiation group vs. 82.4% in the control group, P = 0.03).Breast-cancer mortality was lower among patients in the nodal-irradiation group than among patients in the control group in the EORTC trial.The number needed to treat to avoid one death from breast cancer was 39.As stated by Burstein and Morrow in the accompanying editorial, better "treatment selection for the individual patient" is probably needed. 3Because internal mammary irradiation carries a small risk of cardiac toxic effects, it should be offered selectively. 1 We suggest that lymphoscintigraphy can be helpful.Almost all patients with breast cancer who have T1 or T2 tumors (small tumors) and N0 nodes (no clinically detectable regional lymph-node involvement) currently undergo an axillary sentinel-node biopsy.In a review of the literature, presurgery lymphoscintigraphy showed physiologic drainage from a peritumoral injection site to the internal mam-mary basin in approximately 20% of patients. 4Also, an analysis of the published data showed that when internal mammary drainage was present and an axillary sentinel node was found to be positive, the risk of concomitant invasion to the internal mammary nodes was higher than 40% (75 of 183 patients). 5