Factors associated with the development of breast cancer-related lymphedema after whole-breast irradiation

Purpose To determine the rates of breast cancer–related lymphedema (BCRL) in patients undergoing whole-breast irradiation as part of breast-conserving therapy (BCT) and to identify clinical, pathologic, and treatment factors associated with its development. Methods and Materials A total of 1,861 patients with breast cancer were treated at William Beaumont Hospital with whole-breast irradiation as part of their BCT from January 1980 to February 2006, with 1,497 patients available for analysis. Determination of BCRL was based on clinical assessment. Differences in clinical, pathologic, and treatment characteristics between patients with BCRL and those without BCRL were evaluated, and the actuarial rates of BCRL by regional irradiation technique were determined. Results The actuarial rate of any BCRL was 7.4% for the entire cohort and 9.9%, 14.7%, and 8.3% for patients receiving a supraclavicular field, posterior axillary boost, and internal mammary irradiation, respectively. BCRL was more likely to develop in patients with advanced nodal status (11.4% vs. 6.3%, p = 0.001), those who had a greater number of lymph nodes removed (14 nodes) (9.5% vs. 6.0%, p = 0.01), those who had extracapsular extension (13.4% vs. 6.9%, p = 0.009), those with Grade II/III disease (10.8% vs. 2.9%, p p = 0.02). Regional irradiation showed small increases in the rates of BCRL ( p = not significant). Conclusions These results suggest that clinically detectable BCRL will develop after traditional BCT in up to 10% of patients. High-risk subgroups include patients with advanced nodal status, those with more nodes removed, and those who receive chemotherapy, with patients receiving regional irradiation showing a trend toward increased rates.