ACR Appropriateness Criteria® rectal cancer: metastatic disease at presentation.

The management of rectal cancer in patients with metastatic disease at presentation is highly variable. There are no phase III trials addressing therapeutic approaches, and the optimal sequencing of chemotherapy, radiation therapy, and surgery remains unresolved. Although chemoradiation is standard for patients with stage II/III rectal cancer, its role in the metastatic setting is controversial. Omitting chemoradiation may not be appropriate in all stage IV patients, particularly those with symptomatic primary tumors. Moreover, outcomes in this setting are vastly different, as some treatments carry the potential for cure in selected patients, while others are purely palliative. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application, by the panel, of a well-established consensus methodology (Modified Delphi) to rate the appropriateness of imaging and treatment procedures. In instances in which evidence is lacking or not definitive, expert opinion may be used as the basis for recommending imaging or treatment.