LAUSR

BackgroundGuidelines recommend neoadjuvant therapy (NT) for clinical stage II–III (locally advanced) rectal adenocarcinoma, but utilization remains suboptimal. The causes of NT omission remain poorly understood.MethodsThe main outcomes in this study of patients with resected clinically non-metastatic rectal adenocarcinoma in the 2010–2015 National Cancer Database were local staging utilization in patients with non-metastatic tumors (i.e., undocumented clinical stage/pathologic stage I–III) and NT utilization for locally advanced tumors. Multivariable regression was used to examine predictors of these outcomes. Facility-specific risk- and reliability-adjusted local staging and NT rates were calculated. Positive margins and overall survival (OS) were examined as secondary outcomes.ResultsLocal staging was omitted in 7737/43,819 (17.7%) patients with clinically non-metastatic tumors and NT was omitted in 5199/31,632 (16.4%) patients with locally advanced tumors. NT was utilized in 24,826 (91.1%) locally advanced patients who had local staging vs. 1607 (36.6%) patients who did not; 2785 (53.6%) locally advanced patients with NT omitted also had local staging omitted. Treatment at facilities with lowest quintile local staging rates was associated with NT omission (relative risk 2.41, 95% confidence interval 2.11, 2.75). Adjusted facility local staging rates varied sixfold (16.1–98.0%), facility NT rates varied twofold (43.9–95.9%), and they were correlated (r = 0.58; P < 0.001). Local staging omission and NT omission were independently associated with positive margins and decreased OS.ConclusionsLocal staging omission is a common care process in over half of cases of omitted NT. These data emphasize the need for quality improvement efforts directed at providing facilities feedback about their local staging rates.