In Reply In our recent study entitled “Time Trend Analysis of Primary Tumor Resection for Stage IV Colorectal Cancer: Less Surgery, Improved Survival,”1 we noted a trend toward improved survival despite decreasing primary tumor resection (PTR) rates for patients presenting with unresectable metastatic colorectal cancer (MCRC). We observed improvements in survival that coincided with the availability of new systemic treatment options. However, more than 50% of patients who present with MCRC are still undergoing PTR. Based on these results, we concluded that PTR may be overused among patients with MCRC. As noted by Price and colleagues, to date, little is known about the effect of PTR on survival. Although multiple retrospective studies have associated PTR with a survival benefit, these studies are subject to the strong confounding effects of treatment selection, and survivor time biases limit the interpretation of their findings (eg, patients undergoing PTR may be less likely than patients not undergoing PTR to have an advanced disease burden or comorbid conditions).
Hu C, Bailey CE, Chang GJ. Less Surgery, Improved Survival From Stage IV Colorectal Cancer?—Reply. JAMA Surg. 2015;150(8):819-820. doi:10.1001/jamasurg.2015.0683