title: National Trends in Nonoperative Management of Rectal Adenocarcinoma.
abstract: Neoadjuvant chemoradiation for stage II/III rectal cancer results in up to 49% of patients with a clinical complete response. As a result, many have questioned whether surgery can be omitted for this group of patients. Currently, there is insufficient evidence for chemoradiation only, or nonoperative management (NOM), to support its adoption. Despite this, anecdotal evidence suggests there is a trend toward increased use of NOM. Our objective was to examine the use of NOM for rectal cancer over time, as well as the patient- and facility-level factors associated with its use.
  
  
  
  We included all incident cases of invasive, nonmetastatic rectal adenocarcinoma reported to the National Cancer Database from 1998 to 2010. We performed univariate and multivariate analyses to assess for NOM use over time, as well as associated patient- and facility-level factors.
  
  
  
  A total of 146,135 patients met the inclusion criteria: 5,741 had NOM and 140,394 had surgery with or without additional therapy. From 1998 to 2010, NOM doubled, from 2.4% to 5% of all cases annually. Patients who were black (adjusted odds ratio [AOR], 1.71; 95% CI, 1.57 to 1.86), uninsured (AOR, 2.35; 95% CI, 2.08 to 2.65) or enrolled in Medicaid (AOR, 2.10; 95% CI, 1.90 to 2.33), or treated at low-volume facilities (AOR, 1.53; 95% CI, 1.42 to 1.64) were more likely to receive NOM than were patients who were white, privately insured, and treated at a high-volume facility, respectively.
  
  
  
  NOM demonstrates promise for the treatment of rectal cancer; currently, however, the most appropriate strategy is to pursue this approach with well-informed patients in the context of a clinical trial. We observed evidence of increasing NOM use, with this increase occurring more frequently in black and uninsured/Medicaid patients, raising concern that increased NOM use may actually represent increasing disparities in rectal cancer care rather than innovation. Further studies are needed to assess survival differences by treatment strategy.
authors.affiliation: All authors: University of North Carolina, Chapel Hill, NC. clayton.ellis@unchealth.unc.edu.
authors.forename: Clayton Tyler
authors.initials: CT
authors.lastname: Ellis
authors.affiliation: All authors: University of North Carolina, Chapel Hill, NC.
authors.forename: Cleo A
authors.initials: CA
authors.lastname: Samuel
authors.affiliation: All authors: University of North Carolina, Chapel Hill, NC.
authors.forename: Karyn B
authors.initials: KB
authors.lastname: Stitzenberg
mesh_terms: D000230:Adenocarcinoma / Q000453:epidemiology / Q000473:pathology / Q000628:therapy*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059248:Chemoradiotherapy / Q000639:trends; D015331:Cohort Studies; D016208:Databases, Factual; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000453:epidemiology / Q000473:pathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy / Q000639:trends; D009367:Neoplasm Staging; D014481:United States / Q000453:epidemiology