Development of a Predictive Nomogram for Circumferential Resection Margin in Rectal Cancer Surgery.

INTRODUCTION: Circumferential resection margin (CRM) is a key quality metric and predictor of oncologic outcomes and overall survival following surgery for rectal cancer. We aimed to develop a nomogram to identify patients at risk for a positive CRM in the preoperative setting. METHODS: We performed a retrospective evaluation of the National Cancer Database from 2010 to 2014 for patients with clinical stage I-III rectal cancer who underwent total mesorectal excision. Patients were excluded for emergency operation, resection for cancer recurrence, palliative resection, transanal resection, and missing CRM status. The primary outcome was positive CRM. Secondary outcomes included overall survival. RESULTS: There were 28,790 patients included. 2245 (7.8%) had a positive CRM. Higher tumor grade, lack of neoadjuvant chemotherapy, mucinous/signet tumor histology, open approach, abdominoperineal resection, higher T stage, lymphovascular invasion, and perineural invasion were all significantly associated with positive CRM (P < 0.05) and were included in the nomogram. The C-statistic was 0.703, suggesting a good predictive model. CONCLUSIONS: Positive CRM is associated with specific patient demographics and tumor characteristics. These factors can be used along with preoperative MRI to predict CRM positivity in the preoperative period and plan accordingly.

Surgically-relevant quality of life thresholds for the Short Inflammatory Bowel Disease Questionnaire in Crohn's disease.

BACKGROUND: Despite growing interest in patient-reported outcome measures to track the progression of Crohn's disease, frameworks to apply these questionnaires in the preoperative setting are lacking. Using the Short Inflammatory Bowel Disease Questionnaire (sIBDQ), this study aimed to describe the interpretable quality of life thresholds and examine potential associations with future bowel resection in Crohn's disease. METHODS: Adult patients with Crohn's disease completing an sIBDQ at a clinic visit between 2020 and 2022 were eligible. A stoplight framework was adopted for sIBDQ scores, including a "Resection Red" zone suggesting poor quality of life that may benefit from discussions about surgery as well as a "Nonoperative Green" zone. Thresholds were identified with both anchor- and distribution-based methods using receiver operating characteristic curve analysis and subgroup percentile scores, respectively. To quantify associations between sIBDQ scores and subsequent bowel resection, multivariable logistic regression models were fit with covariates of age, sex assigned at birth, body mass index, medications, disease pattern and location, resection history, and the Harvey Bradshaw Index. The incremental discriminatory value of the sIBDQ beyond clinical factors was assessed through the area under the receiver operating characteristics curve (AUC) with an internal validation through bootstrap resampling. RESULTS: Of the 2003 included patients, 102 underwent Crohn's-related bowel resection. The sIBDQ Nonoperative Green zone threshold ranged from 61 to 64 and the Resection Red zone from 36 to 38. When adjusting for clinical covariates, a worse sIBDQ score was associated with greater odds of subsequent 90-day bowel resection when considered as a 1-point (odds ratio [OR] [95% CI], 1.05 [1.03-1.07]) or 5-point change (OR [95% CI], 1.27 [1.14-1.41]). Inclusion of the sIBDQ modestly improved discriminative performance (AUC [95% CI], 0.85 [0.85-0.86]) relative to models that included only demographics (0.57 [0.57-0.58]) or demographics with clinical covariates (0.83 [0.83-0.84]). CONCLUSION: In the decision-making process for bowel resection, disease-specific patient-reported outcome measures may be useful to identify patients with Crohn's disease with poor quality of life and promote a shared understanding of personalized burden.