We thank Drs. Glantzounis and Katsios for their valuable observations.

We have to state, however, that our findings are similar to those of other investigators. Martin et al. [5] reported that simultaneous resections had fewer complications (49 vs. 67%; P = 0.01), shorter median hospital stays (10 vs. 18 days; P = 0.01), and similar mortality rates (2.2 vs. 2.8%; P = NS) when compared to staged procedures. Moreover, when comparing patients who underwent major liver resections (lobectomy or more), those with simultaneous surgeries had a lower morbidity rate (60 vs. 70%; P = 0.03), shorter operating times, decreased hospital stays, and a twofold decrease in laparotomy complications. Capussotti et al. [2, 3] and Martin et al. [5] reported that the combined morbidity was greater after staged procedures than after simultaneous resections, with no difference in mortality. Martin et al. [5] reported no difference in severe morbidities. A recent metanalysis by Chen et al. [4] and a multicenter study by Brouquet et al. [1] showed that simultaneous resections (when feasible) were associated with improved morbidity and mortality, diminished use of blood products, and equivalent long-term oncologic benefit. Continuous improvements in biomarkers as well as chemotherapy regimens will allow for improved results, both in simultaneous resections and in staged resections.

Until a prospective randomized study is carried out, all studies will suffer to a greater or lesser extent from the potential drawbacks outlined in the letter from Glantzounis and Katsios. However, it is our hope that they will consider the mounting evidence in support of simultaneous resection of colorectal metastases.