To the Editor—I read with interest the article by Law et al.1 addressing oncologic outcome after anterior resection for Stage II rectal adenocarcinoma. Unfortunately, the data provided in the article do not support the authors’ arguments regarding the lack of benefit of neoadjuvant radiotherapy for patients with rectal cancer.

The exclusion of patients undergoing neoadjuvant therapy, those undergoing abdominoperineal resection (APR), those undergoing noncurative resection, and most importantly, those ultimately proven to have Stage III disease, makes any conclusion the authors make regarding lack of benefit of neoadjuvant radiotherapy suspect. Given the imprecision of our current pretreatment staging methods, a surgeon cannot accurately predict which patients will beultimately proven to have “optimal” Stage II tumors on final histology. Retrospectively selecting these “optimal” patients for analysis, while excluding those with unfavorable features, introduces selection bias.

Given the accumulating data that postoperative radiotherapy has less oncologic benefit and greater toxicity than preoperative radiotherapy,2 it is difficult to accept the authors’ premise that neoadjuvant radiotherapy is unnecessary. If one chooses not to use neoadjuvant radiotherapy, and the patient has a positive resection margin or Stage III disease, the optimal treatment window for radiotherapy has most likely passed.

In addition, the finding that their selected, optimal patients (Stage II, negative resection margins, nonfixed, non-APR) had a local pelvic recurrence rate of 6 percent could be interpreted to be an argument for neoadjuvant radiotherapy. The local recurrence rate after neoadjuvant radiotherapy plus proctectomy in series of unselected patients with pretreatment Stages II and III disease (including patients undergoing APR and patients with fixed tumors) is only 6 percent.3 Additionally, univariate analysis in the Dutch rectal cancer trial revealed that neoadjuvant radiotherapy reduced local recurrence in Stage II patients compared with surgery alone.4

Decisions regarding the use of neoadjuvant radiotherapy for patients with rectal cancer should be based on data from studies that include all patients who undergo treatment with curative intent, rather than on data regarding highly selected patients identified by retrospective subgrouping.