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About · curated by Nick Boehling, MD · @nb2276

2026-06-21

digest generated 2026-06-22

ARS AUC, locoregionally recurrent rectal cancer: R0 resection drives survival/LC; preop chemo/RT + reirradiation endorsed to enable resection, no practice change.
Quiet day: one lower-GI consensus document. The new ARS appropriate-use criteria reaffirm R0 (margin-negative) resection as the determinant of survival and local control, with preop chemo/RT and reirradiation endorsed to downsize toward resectability. Consensus-driven (76 of 116 refs retrospective, only 10 RCTs); reaffirms combined-modality practice rather than changing it.

GI Lower

Guideline, not a trial; reirradiation endorsed to facilitate R0 resection, though dose/fractionation aren't specified in source.

ARS Appropriate Use Criteria: Locoregionally Recurrent Rectal Cancer

TL;DRR0 (margin-negative) resection drives survival and local control; preop chemo/RT and reirradiation aid downsizing; consensus advises no major practice change.

vs leading data
  • Updates the 2012 ACR recurrent rectal cancer AUC; 13 of 43 original citations retained

Combined Curative Consensus / guideline

8 details 5 trials watching
  • 🔍 Systematic review + modified Delphi (RAND/UCLA) consensus; multispecialty panel (colorectal surgery, rad onc, med onc, GI, radiology)
  • 🔍 Evidence base: 116 references, Jan 2013–Jul 2025
    • 10 well-designed RCTs (phase 2/3)
    • 29 matched-cohort / phase 2
    • 76 retrospective
    • 1 meta-analysis
  • 💊 Preop systemic therapy, RT, or both → downsizing to improve likelihood of R0 resection
  • 🔍 RT/reirradiation is 1 of 5 explicit PICO questions; reirradiation endorsed to facilitate resection (dose/fractionation not reported in source)
  • 🔍 Workup: high-res pelvic MRI preferred (sidewall/sacral/nerve involvement); FDG-PET separates fibrosis from tumor; CEA + emerging ctDNA
  • 📊 R0 (margin-negative) resection is the stated ultimate determinant of survival and local control
  • ⚠️ Weak evidence base: 76 of 116 references retrospective, only 10 well-designed RCTs
  • ⚠️ Guideline summary (no effect sizes reported in source); reaffirms combined-modality practice rather than changing it

Sourced from Miller, Eric D. et al.

📚 Sources · 📄 1 paper
📄 PAPER Miller, Eric D.; Jethwa, Krishan R.; Dozois, Eric et al. · Cancer (2026-06)
Executive summary of American Radium Society Appropriate Use Criteria for the treatment of locoregionally recurrent rectal cancer
Abstract
Abstract This literature‐based systematic review and associated guidelines provide evidence‐based paradigms for the management of locoregionally recurrent rectal cancer (LRRC). This multispecialty committee included gastrointestinal radiation and medical oncology, gastroenterology, radiology, and colorectal surgery. As is the standard, the previously described American Radium Society Appropriate Use Criteria methodology for this project was followed rigorously, with the Population, Intervention, Comparator, Outcome, Timing, and Study Design framework and Preferred Reporting Items for Systematic Reviews and Meta‐Analyses methodology to assess the evidence. RAND/University of California Los Angeles consensus methodology (modified Delphi) was used to rate the appropriateness of treatment options. Published between January 1, 2013, and July 16, 2025, 116 peer‐reviewed trials provided the evidence: 10 were well‐designed randomized phase 2/3 trials, 29 were moderately well designed trials that accounted for most common biases (matched cohort and phase 2), 76 trials had design limitations (retrospective), and one was a meta‐analysis. Clinical cases were created as examples to illustrate current acceptable management of LRRC. Treatment and prognosis are influenced by prior therapy and the site(s) and extent of LRRC. The ability to achieve a margin‐negative surgical resection is the ultimate determinant of survival and local control. Preoperative systemic therapy, radiation therapy, or a combination of the two can facilitate tumor downsizing and improve the likelihood of a margin‐negative resection. An individualized multidisciplinary approach is required to ensure the best outcome. Although this review does not suggest a major alteration of current practice, it provides reassuring evidence of the importance of combined‐modality therapy.
📝 https://doi.org/10.1002/cncr.70464