The role of rectal magnetic resonance imaging in accurate localization and designation of colorectal cancer for optimal management: Case study.

Colorectal cancer, developing from malignant transformation of the distal gut epithelium, is the second leading cause of cancer death in the United States. We present a gentleman in his 60s who was diagnosed with colorectal cancer during a routine screening colonoscopy with no evidence of distant metastasis on subsequent staging with positron emission tomography and computed tomography (PET-CT). The outside rectal MR (magnetic resonance) imaging report localized a mass to the upper rectum. Review of the MRI at an institutional, Multidisciplinary Tumor Board designated the tumor as "rectosigmoid," straddling the rectosigmoid junction at the level of the "sigmoid take-off" (STO) or alternatively at the level of the last sigmoid artery take-off (SAT) at the origin of the superior rectal artery. The anatomic differentiation between upper rectal and lower sigmoid colon cancers carries clinical importance which is highlighted in this case report and brief literature review. Optimal anatomic localization of colorectal cancers helps direct the clinical team to tailor an individualized patient care plan.

Which Treatment for Which Patient: Rectal Cancer Management After PROSPECT Trial.

Determining treatment options for patients with locally advanced rectal cancer after the PROSPECT trial data readout adds an important level to the decision-making process.

Spectrum of somatic mutational features of colorectal tumors in ancestrally diverse populations.

Ancestrally diverse and admixed populations, including the Hispanic/Latino/a/x/e community, are underrepresented in cancer genetic and genomic studies. Leveraging the Latino Colorectal Cancer Consortium, we analyzed whole exome sequencing data on tumor/normal pairs from 718 individuals with colorectal cancer (128 Latino, 469 non-Latino) to map somatic mutational features by ethnicity and genetic ancestry. Global proportions of African, East Asian, European, and Native American ancestries were estimated using ADMIXTURE. Associations between global genetic ancestry and somatic mutational features across genes were examined using logistic regression. TP53 , APC , and KRAS were the most recurrently mutated genes. Compared to non-Latino individuals, tumors from Latino individuals had fewer KRAS (OR=0.64, 95%CI=0.41-0.97, p=0.037) and PIK3CA mutations (OR=0.55, 95%CI=0.31-0.98, p=0.043). Genetic ancestry was associated with presence of somatic mutations in 39 genes (FDR-adjusted LRT p<0.05). Among these genes, a 10% increase in African ancestry was associated with significantly higher odds of mutation in KNCN (OR=1.34, 95%CI=1.09-1.66, p=5.74×10 -3 ) and TMEM184B (OR=1.53, 95%CI=1.10-2.12, p=0.011). Among RMGs, we found evidence of association between genetic ancestry and mutation status in CDC27 (LRT p=0.0084) and between SMAD2 mutation status and AFR ancestry (OR=1.14, 95%CI=1.00-1.30, p=0.046). Ancestry was not associated with tumor mutational burden. Individuals with above-average Native American ancestry had a lower frequency of microsatellite instable (MSI-H) vs microsatellite stable tumors (OR=0.45, 95%CI=0.21-0.99, p=0.048). Our findings provide new knowledge about the relationship between ancestral haplotypes and somatic mutational profiles that may be useful in developing precision medicine approaches and provide additional insight into genomic contributions to cancer disparities. Significance: Our data in ancestrally diverse populations adds essential information to characterize mutational features in the colorectal cancer genome. These results will help enhance equity in the development of precision medicine strategies.

Functional quality of life among newly diagnosed young adult colorectal cancer survivors compared to older adults: results from the ColoCare Study.

PURPOSE: Colorectal cancer (CRC) incidence and mortality are increasing among young adults (YAs) aged 18-39. This study compared quality of life (QOL) between YA and older adult CRC survivors in the ColoCare Study. METHODS: Participants were grouped by age (years) as follows: 18-39 (YA), 40-49, 50-64, and 65 + . Functional QOL (physical, social, role, emotional, cognitive) and global QOL were assessed with the EORTC-QLQ-C30 at enrollment, 3, 6, and 12 months. Average scores were compared between groups over time using longitudinal mixed-effect modeling. Proportions with clinically meaningful QOL impairment were calculated using age-relevant thresholds and compared between groups over time using logistic regression with mixed effects. RESULTS: Participants (N = 1590) were n = 81 YAs, n = 196 aged 40-49, n = 627 aged 50-64, and n = 686 aged 65 + . Average physical function was better among YAs than participants aged 50-64 (p = 0.010) and 65 + (p < 0.001), and average social function was worse among YAs than aged 65 + (p = 0.046). Relative to YAs, all age groups were less likely to report clinically meaningful social dysfunction (aged 40-49 OR = 0.13, 95%CI = 0.06-0.29; aged 50-64 OR = 0.10, 95%CI = 0.05-0.21; aged 65 + OR = 0.07, 95%CI = 0.04-0.15) and role dysfunction (aged 40-49 OR = 0.36, 95%CI = 0.18-0.75; aged 50-64 OR = 0.41, 95%CI = 0.22-0.78; aged 65 + OR = 0.32, 95%CI = 0.17-0.61). Participants aged 40-49 were also less likely to report physical dysfunction (OR = 0.42, 95%CI = 0.19-0.93). CONCLUSION: YA CRC survivors reported better physical and worse social function compared to older CRC survivors, and YA CRC survivors were more likely to report clinically meaningful social, role, and physical disfunction. Future work should further investigate QOL using age-relevant benchmarks to inform best practices for CRC survivorship care. TRIAL REGISTRATION: NCT02328677, registered December 2014.

Impact of neoadjuvant therapy on nodal harvest in clinical stage III rectal cancer: Establishing optimum cut-offs by disease response.

INTRODUCTION: A minimum lymph node harvest (LNH) of 12 is the current standard for appropriate nodal staging in resectable rectal cancer. However, the rise of neoadjuvant chemoradiation (NCRT) and total neoadjuvant therapy (TNT) has been associated with decreasing number of LNH. We hypothesize that as tumor response to neoadjuvant therapy increases, the optimum for LNH to achieve appropriate nodal staging should decrease. METHODS: Patients with clinical stage III rectal adenocarcinoma who underwent NCRT/TNT followed by resection were identified from the National Cancer Database. A JoinPoint regression analysis was used to determine the LNH for each tumor regression grade (TRG) category beyond which the rate of positive nodes does not significantly change. RESULTS: Thirteen thousand four hundred and twenty-six patients met inclusion criteria. Of these, 2406 (17.9%) achieved TRG 0 or ypT0 and 8210 (61.2%) achieved ypN0. Collectively, 2043 patients (15.2%) were reported to have a pathologic complete response (ypT0 ypN0). Positive pathologic nodes were found in 15%, 23%, 31%, 54%, and 53% as ypT stage increased from ypT0 to ypT4, respectively. Similarly, ypN+ rates were 15%, 36%, 41%, and 55% in TRG 0-3. No JoinPoint was identified for TRG 0, whereas inflection points were found at 6-10 nodes for TRG1 (p = 0.002) and TRG 2 (p = 0.016), and at 11-15 nodes for TRG 3. CONCLUSION: The benchmark of retrieving 12 nodes in resectable stage III rectal cancer is not consistently achieved after NCRT/TNT. We demonstrate that the LNH requirement to establish accurate pathologic nodal staging can vary depending on the tumor response to neoadjuvant therapies.

Clinical Tools for Rectal Cancer Response Assessment following Neoadjuvant Treatment in the Era of Organ Preservation.

Local tumor response evaluation following neoadjuvant treatment(s) in rectal adenocarcinoma requires a multi-modality approach including physical and endoscopic evaluations, rectal protocoled MRI, and cross-sectional imaging. Clinical tumor response exists on a spectrum from complete clinical response (cCR), defined as the absence of clinical evidence of residual tumor, to near-complete response (nCR), which assumes a significant reduction in tumor burden but with increased uncertainty of residual microscopic disease, to incomplete clinical response (iCR), which incorporates all responses less than nCR that is not progressive disease. This article aims to review the clinical tools currently routinely available to evaluate treatment response and offers a potential management approach based on the extent of local tumor response.

Return to intended oncologic therapy after colectomy for stage III colon adenocarcinoma: Does surgical approach matter?

AIM: Return to intended oncologic treatment (RIOT) is an important paradigm for surgically resected cancers requiring multimodal treatment. Benefits of minimally invasive colectomy (MIC) may allow earlier initiation of adjuvant chemotherapy (ACT) and have associated survival benefits. We sought to determine if operative approach affects RIOT timing in resected stage III colon cancer. METHODS: NCDB identified pathological stage III colon adenocarcinoma patients who underwent resection and received ACT. Propensity score matching and kernel density estimation compared operative approaches and conversion impact on intervals to RIOT. RESULTS: A total of 15,132 open colectomies (OC) versus 14,107 MIC were included. MIC patients had two-days shorter median length of stay (LOS) (4 vs. 6 days; p < 0.001), one-week shorter median time to RIOT (6 vs. 7 weeks; p = 0.015) comparing 12,867 matched pairs. There was no difference in time interval to RIOT between the LC versus RC, converted MIC vs. OC groups. MIC was a favourable predictor of earlier RIOT (HR 1.14 [1.07-1.22]; p < 0.001). CONCLUSION: MIC in stage III colon cancer is associated with a shorter time to RIOT when compared to OC. Since timely initiation of ACT may influence cancer outcome, MIC may be oncologically preferable. Prospective studies are needed to assess RIOT and survival outcomes in stage III colon cancer.

Associations of combined physical activity and body mass index groups with colorectal cancer survival outcomes.

BACKGROUND: Physical activity and BMI have been individually associated with cancer survivorship but have not yet been studied in combinations in colorectal cancer patients. Here, we investigate individual and combined associations of physical activity and BMI groups with colorectal cancer survival outcomes. METHODS: Self-reported physical activity levels (MET hrs/wk) were assessed using an adapted version of the International Physical Activity Questionnaire (IPAQ) at baseline in 931 patients with stage I-III colorectal cancer and classified into 'highly active' and'not-highly active'(≥ / < 18 MET hrs/wk). BMI (kg/m2) was categorized into 'normal weight', 'overweight', and 'obese'. Patients were further classified into combined physical activity and BMI groups. Cox-proportional hazard models with Firth correction were computed to assess associations [hazard ratio (HR), 95% profile HR likelihood confidence interval (95% CI) between individual and combined physical activity and BMI groups with overall and disease-free survival in colorectal cancer patients. RESULTS: 'Not-highly active' compared to 'highly active' and 'overweight'/ 'obese' compared to 'normal weight' patients had a 40-50% increased risk of death or recurrence (HR: 1.41 (95% CI: 0.99-2.06), p = 0.03; HR: 1.49 (95% CI: 1.02-2.21) and HR: 1.51 (95% CI: 1.02-2.26), p = 0.04, respectively). 'Not-highly active' patients had worse disease-free survival outcomes, regardless of their BMI, compared to 'highly active/normal weight' patients. 'Not-highly active/obese' patients had a 3.66 times increased risk of death or recurrence compared to 'highly active/normal weight' patients (HR: 4.66 (95% CI: 1.75-9.10), p = 0.002). Lower activity thresholds yielded smaller effect sizes. CONCLUSION: Physical activity and BMI were individually associated with disease-free survival among colorectal cancer patients. Physical activity seems to improve survival outcomes in patients regardless of their BMI.

Tumor Response-speed Heterogeneity as a Novel Prognostic Factor in Patients With Metastatic Colorectal Cancer.

PURPOSE: Differential tumor response to therapy is partially attributed to tumor heterogeneity. Additional efforts are needed to identify tumor heterogeneity parameters in response to therapy that is easily applicable in clinical practice. We aimed to describe tumor response-speed heterogeneity and evaluate its prognostic value in patients with metastatic colorectal cancer. PATIENTS AND METHODS: Individual patient data from Amgen (NCT00364013) and Sanofi (NCT00305188; NCT00272051) trials were retrieved from Project Data Sphere. Patients in the Amgen 5-fluorouracil, leucovorin, oxaliplatin (FOLFOX) arm were used to establish response-speed heterogeneity. Its prognostic value was subsequently validated in the Sanofi FOLFOX arms and the Amgen panitumumab+FOLFOX arm. Kaplan-Meier method and Cox proportional hazards models were used for survival analyses. RESULTS: Patients with high response-speed heterogeneity in the Amgen FOLFOX cohort had significantly shorter ( P <0.001) median progression-free survival (PFS) of 7.27 months (95% CI, 6.12-7.96 mo) and overall survival (OS) of 16.0 months (95% CI, 13.8-18.2 mo) than patients with low response-speed heterogeneity with median PFS of 9.41 months (95% CI, 8.75-10.89 mo) and OS of 22.4 months (95% CI, 20.1-26.7 mo), respectively. Tumor response-speed heterogeneity was a poor prognostic factor of shorter PFS (hazard ratio, 4.17; 95% CI, 2.49-6.99; P <0.001) and shorter OS (hazard ratio, 2.57; 95% CI, 1.64-4.01; P <0.001), after adjustment for other common prognostic factors. Comparable findings were found in the external validation cohorts. CONCLUSION: Tumor response-speed heterogeneity to first-line chemotherapy was a novel prognostic factor associated with early disease progression and shorter survival in patients with metastatic colorectal cancer.

A Novel Nomogram for Early Identification and Intervention in Colorectal Cancer Patients at Risk for Malnutrition.

BACKGROUND: Malnutrition is under-recognized in cancer patients and can lead to poor treatment outcomes. We aim to develop an outpatient-focused score based on the Malnutrition Screening Tool (MST) to help identify colorectal cancer (CRC) profiles at high risk for malnutrition. METHODS: 506 CRC patients during initial outpatient oncology consultation at our tertiary referral outpatient oncology clinic completed the MST. Objective and subjective data were collected through chart review. Data gathered are as follows: demographics, anthropometrics, laboratory values, patient-reported symptoms, MST score, cancer history, performance status, socioeconomic status, and Charlson Comorbidity. Predictors of malnutrition were identified by logistic regression. Receiver operating curve (ROC), area under the curve (AUC), and our model's predictability were determined. RESULTS: Significant predictors of malnutrition are as follows: younger age (20-39 vs >40 years) (P = .007), normal-to-low body mass index at presentation (P = .019), Eastern Cooperative Oncology Group classification 2-3 (P = .012), metastatic disease (P = .046), albumin <3.0 g/dL (P = .033), fatigue (P < .001), and change in stool/bowel habits (P = .002). In our derived malnutrition score, risk of malnutrition increased from 11% for score 0, to 100% for scores 9-10. Receiver operating curve showed AUC .745 (95% CI, .697-.793). DISCUSSION: An outpatient clinic-derived malnutrition score obtained from objective and patient-reported variables may facilitate identification of CRC patients at highest risk for malnutrition. Rapid identification and intervention in high-risk patients may improve treatment recovery, therapy tolerance, and quality of life. Our tool requires external validation before application in clinical practice.

Neoadjuvant rectal score is prognostic for survival: A population-based propensity-matched analysis.

INTRODUCTION: Neoadjuvant rectal (NAR) score may serve as a surrogate short-term endpoint for overall survival (OS) in clinical trials. This study aims to test the NAR score using a large, national cancer registry. METHODS: National Cancer Database patients with clinical stage II/III rectal adenocarcinoma (RAC) treated with neoadjuvant chemoradiation (CRT) followed by surgery were selected and divided into low-, intermediate-, and high-NAR subgroups. OS outcomes were analyzed using Kaplan-Meier and logistic regression models. RESULTS: A total of 12 452 patients were selected, of which 5071 (40.7%) were in clinical stage II and 7381 (59.3%) were in clinical stage III; 15.2% had pathologic complete response. The mean NAR score was 10.01 ± 10.61. Six thousand nine hundred and forty-one (55.7%) did not receive adjuvant chemotherapy (AC) and were propensity-matched across NAR subgroups (966 in each group). A significant difference in 5-year OS between low-, intermediate-, and high-NAR groups was observed (85% vs. 76% vs. 68%; p < 0.001). Five thousand five hundred and eleven (44.3%) received AC and 1045 triplets were propensity-matched per NAR groups. A significant difference was again observed for 5-year OS (93% vs. 88% vs. 75%; p < 0.001). Logistic regression confirmed NAR strata as a significant predictor of 5-year OS. CONCLUSION: NAR score, as a neoadjuvant response measure, is a strong predictor of 5-year OS, regardless of AC receipt in a heterogenous population of locally advanced RAC patients.

Management of Malignant Small Bowel Obstruction: Is Intestinal Bypass Effective Palliation?

BACKGROUND/PURPOSE: Malignant small bowel obstruction (mSBO) is a common consequence of advanced malignancies. Surgical consultation is common, however data on the outcomes following an operation are lacking. We investigated a specific operative approach-intestinal bypass-to determine the outcomes associated with this intervention. METHODS: Patients with a preoperative diagnosis of mSBO who underwent intestinal bypass between 2015 and 2021 were included. Isolated colonic obstruction was excluded as was gastric outlet obstruction. Perioperative and postoperative outcomes were measured, including complications, overall survival, return to oral intake, and return to intended oncologic therapy. Patients were additionally grouped as to whether the operation was performed as elective or as inpatient. RESULTS: Overall, 55 patients were identified, with a mean age of 61.2 ± 14 years. The most common primary malignancy was colorectal cancer (65.5%) and 80% of patients had a preoperative diagnosis of metastatic disease. Small bowel to colon was the most common bypass procedure (51%). Severe complications occurred in 25.5% of patients with three in-hospital mortalities (5.5%). Survival rates at 30, 90, and 180 days were 91%, 80%, and 62%, respectively. The majority of patients were discharged to home (85.5%) and were tolerating an oral diet (74.6%). Twenty-seven patients (49.1%) returned to some form of oncologic treatment. CONCLUSIONS: Patients with mSBO face a potentially terminal condition. In this study, approximately 75% of patients who underwent intestinal bypass were able to regain the ability to eat, and 49% returned to oncologic therapy. Although retrospective, these data suggest the approach is efficacious for palliation of this difficult sequela of advanced cancer.

Human Epidermal Growth Factor Receptor 2-Targeting Approaches for Colorectal Cancer: Clinical Implications of Novel Treatments and Future Therapeutic Avenues.

The treatment paradigm for colorectal cancer (CRC) has changed significantly over the past decade with targeted therapeutics. Human epidermal growth factor receptor 2 (HER2) amplification is seen among 3%-4% of patients with metastatic CRC (mCRC). The biological discovery of HER2 amplification in cancer cells has led to practice-changing drug development for several solid tumors, including breast, gastric, and esophageal cancers. HER2 amplification is now highly actionable in CRC with distinct therapeutic combinations, including the combination of monoclonal antibodies and HER2 receptor-specific tyrosine kinase inhibitors, as well as antibody-drug conjugates, that delivers targeted cytotoxic agents. However, it is essential to define the therapeutic role and sequence of these different combinations, some of which are already part of standard clinical practice. In this review article, we discuss recent clinical studies demonstrating the clinical benefits of each distinct therapeutic approach and their impacts on the current management of HER2-amplified mCRC. We also review ongoing clinical trials targeting the HER2 pathway in mCRC and elaborate on novel therapeutic opportunities in this space that may further define the changing paradigm of HER2-targeted therapy for CRC.

BRAF Mutations Are Associated with Poor Survival Outcomes in Advanced-stage Mismatch Repair-deficient/Microsatellite High Colorectal Cancer.

BACKGROUND: Mismatch repair-deficient (MMR-D)/microsatellite instability-high (MSI-H) metastatic colorectal cancer (mCRC) is a unique disease entity with growing interest given the rise of young-onset CRC. Given its heterogeneous behavior and potential for highly effective treatment outcomes, we sought to identify the clinical and molecular features that offer prognostic value for MMR-D CRC. MATERIALS/METHODS: This was a retrospective cohort study of patients with metastatic CRC with MMR-D or microsatellite instability in a real-world database. Overall survival (OS) was determined by the date of metastatic disease to date of death with stratification made based on factors including BRAF and RAS mutation status, age, and MMR protein loss type. RESULTS: There were 1101 patients in the study. Patients with BRAF mutations had worse OS compared with patients with wild-type BRAF with a median survival of 18.9 months versus 33.2 months (hazard ratio [HR] 1.52, 95% confidence interval [CI]: 1.25-1.86, P < .001). Patients with age >50 were found to have decreased OS versus age ≤50 with a median survival of 21.4 months versus 38.7 months (HR 1.66, 95% CI: 1.33-2.07, P < .001). BRAF mutations and age >50 remained significant predictors of OS in multivariate analysis. CONCLUSION: BRAF mutations and age >50 are associated with worse survival outcomes for patients with MMR-D mCRC. RAS mutations and specific MMR alterations are not associated with survival outcomes.

Phase I Study of Lenvatinib and Capecitabine with External Radiation Therapy in Locally Advanced Rectal Adenocarcinoma.

BACKGROUND: Neoadjuvant chemoradiation with fluoropyrimidine followed by surgery and adjuvant chemotherapy has been the standard treatment of locally advanced stages II and III rectal cancer for many years. There is a high risk for disease recurrence; therefore, optimizing chemoradiation strategies remains an unmet need. Based on a few studies, there is evidence of the synergistic effect of VEGF/PDGFR blockade with radiation. METHODS: In this phase I, dose-escalation and dose-expansion study, we studied 3 different dose levels of lenvatinib in combination with capecitabine-based chemoradiation for locally advanced rectal cancer. RESULTS: A total of 20 patients were enrolled, and 19 were eligible for assessment of efficacy. The combination was well tolerated, with an MTD of 24 mg lenvatinib. The downstaging rate for the cohort and the pCR was 84.2% and 37.8%, respectively. Blood-based protein biomarkers TSP-2, VEGF-R3, and VEGF correlated with NAR score and were also differentially expressed between response categories. The NAR, or neoadjuvant rectal score, encompasses cT clinical tumor stage, pT pathological tumor stage, and pN pathological nodal stage and provides a continuous variable for evaluating clinical trial outcomes. CONCLUSION: The combination of lenvatinib with capecitabine and radiation in locally advanced rectal cancer was found to be safe and tolerable, and potential blood-based biomarkers were identified. CLINICAL TRIAL REGISTRATION: NCT02935309.

Core Homologous Recombination Mutations and Improved Survival in Nonpancreatic GI Cancers.

INTRODUCTION: Homologous recombination mutations (HRM) have led to increased responses to platinum chemotherapy in pancreatic cancer. However, HRMs' role in nonpancreatic gastrointestinal (GI) cancers remains to be determined. Our objective was to evaluate the prognostic and predictive role of core (BRCA1, BRCA2, PALB2) and noncore HRM in nonpancreatic GI cancers receiving platinum therapy. MATERIALS AND METHODS: This study performed at Moffitt Cancer Center included metastatic nonpancreatic GI cancer patients treated with platinum therapy. All patients had either a core or noncore HRM, determined by next generation sequencing. Response rates, median progression-free survival (PFS), and median overall survival (OS) were determined and compared between core versus noncore HRM patients. RESULTS: In the study, 69 patients with one or more HRM were included: 63.8% were male, 87.0% were Caucasian, and 47.9% had colorectal cancer. Twenty-one (30.4%) patients had a core HRM and 48 (69.6%) had a noncore HRM. Among evaluable patients (n=64), there was no significant difference in objective response: 20.0% with core HRM versus 22.7% with noncore HRM responded to platinum therapy (P=0.53). Median PFS was 10.4 months versus 7.1 months for core HRM versus noncore HRM, respectively (P=0.039). Median OS was 68.9 months versus 24.3 months (P=0.026) for core HRM versus noncore HRM, respectively. CONCLUSIONS: Our study demonstrated response of core and noncore HRM to platinum therapy in metastatic nonpancreatic GI malignancies, suggesting benefit in both groups. Core HRM patients had significantly increased median OS and median PFS compared with those with noncore HRM, suggesting potential prognostic and predictive significance. Larger prospective studies are needed to confirm our findings.

Malignant colon polyps: predicting lymph node metastasis following endoscopic excision.

AIM: The risk of lymph node metastasis (LNM) of malignant colon polyps (MCPs) is partly estimated by histologic features of the sampled polyp. However, the routinely available histologic data is limited to tumor grade and status of lymphovascular invasion (LVI). METHODS: The NCDB for colon cancer 2004-2018 was utilized. Patients with pT1Nx adenocarcinoma arising in a polyp and undergoing partial colectomy with ≥ 12 retrieved nodes were selected. NCDB 2004-2017 was used as a training cohort to develop two scoring systems based on a multivariable regression for predictors of LNM including clinical characteristics, grade, and LVI: a nomogram scoring system (NSS) and a simplified scoring system (SSS). These models were internally validated using NCDB 2018 to calculate precision metrics for each model. RESULTS: Six thousand sixty-nine patients were selected in the training cohort. 64.5% of MCPs were in the sigmoid, and LNM rate was 11.2%. Multivariable regression identified younger age, females, hindgut location, higher grade, and LVI as significant predictors of LNM. LNM risk was 1.2% when all unfavorable predictors were absent and exceeded 10% when NSS > 70 or SSS ≥ 3. In the 2018 validation cohort, 723 patients were scored per NSS and SSS, and the negative predictive value for both was 96%. CONCLUSION: Estimating LNM risk in MCPs by applying clinical characteristics along with limited histologic data can help inform decision-making when considering formal oncologic resection. The NSS and SSS demonstrated comparable predictability of LNM among pT1Nx MCPs. The models require external validation and may be strengthened by incorporating additional endoscopic and pathologic characteristics.