Postmastectomy Radiotherapy: Quality Counts!

Extract

It seems like such a simple idea. It is surprising that no one has ever done it before.

In this issue of the Journal, Gebski et al. ( 1 ) from Australia revisit the issue of postmastectomy radiation therapy and its effects on survival with a meta-analysis of 36 trials and a reanalysis of the Early Breast Cancer Trialists' Collaborative Group (EBCTCG) report ( 2 ) . What is new is that Gebski et al. make an effort to control for the quality of radiation therapy in these trials.

The trials were categorized as “optimal” with regard to radiation therapy dose and treatment volume (dose of 40–60 Gy and irradiation of chest wall and regional lymph nodes) or inappropriate with doses and/or treatment volumes outside this range. The authors consider the appropriate volume to be all (emphasis ours) areas at risk for local–regional recurrence or involvement, a statement that seems fairly straightforward and a principle that is central to radiation therapy of most other cancers (e.g., head and neck or rectal). By implication, this would include internal mammary lymph nodes and supraclavicular lymph nodes, a conclusion with which we agree but that is nonetheless quite controversial because of concern for cardiac side effects. Omission of only internal mammary lymph nodes did not cause studies to be classified as inappropriate or suboptimal.