I would like to thank the Archives of Surgery for the opportunity to reply to the thought-provoking comments of Dr Evans. Like Dr Evans, I would challenge the assumption that the American Society of Clinical Oncology guidelines for breast cancer formulated in 2001 are the best guidelines for postmastectomy irradiation, but they are widely used by our radiation oncology colleagues in formulating treatment recommendations. I am also pleased to know that Dr Evans feels that T3N0 (>5 cm in primary tumor size) in isolation is no longer appropriate for postmastectomy irradiation. I applaud her statement that “[t]he dictum that either a tumor size greater than 5 cm or the presence of 4 or more positive nodes is an indication for postmastectomy radiation therapy is no longer valid.” As noted in my discussion1 of the paper by Christante et al,2 a careful review of the recurrence rates of T3N0 breast cancer in patients treated in our institution over the past 20 years fails to identify a benefit for postmastectomy irradiation in this group at a low risk of recurrence without radiation therapy. A manuscript detailing these results has been presented at the Annual Meeting of the North Pacific Surgical Association (November 12-13, 2010; Tacoma, Washington) and has been accepted for publication.3 In this study,3 we showed significant decreases in local, local-regional, and distant recurrence rates and a significant increase in the recurrence-free survival rate in patients at a high risk of recurrence (T1N2 or T1N3 stage, T2N2 or T2N3 stage, and T3N1, T3N2, or T3N3 stage) with postmastectomy irradiation. Unfortunately, the massive meta-analysis study4 referred to by Dr Evans that evaluated 78 prospective trials and 42 000 patients with breast cancer did not do a subgroup analysis combining T and N stage. This leaves the study open to the T3N0 type of error and undermines the study's credibility.
J. David Beatty. “Unnecessary” Postmastectomy Radiation Therapy—Reply. Arch Surg. 2011;146(6):765. doi:10.1001/archsurg.2011.132