Background To construct a modified tumor‐node‐metastasis (TNM) staging system for stage I‐III colon cancer patients with lymph nodes examined (LNE) < 12. Methods The clinicopathological and survival data of 3870 stage I‐III colon cancer patients with LNE < 12 from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015 (development cohort) and 126 stage I‐III patients with LNE < 12 from the Second Affiliated Hospital of Harbin Medical University between 2011 and 2015 (validation cohort) were identified. The optimal stratification of LNR for cancer‐specific survival (CSS) was achieved using X‐tile software. The predictive accuracy of the modified stage (mStage) was determined by the concordance index (C‐index). Results The modified N stage (mN stage) was built based on the LNR (mN0: LNR = 0, mN1: 0 < LNR < 0.4 or cancer nodule formation and mN2: 0.4 ≤ LNR ≤ 1). Preferable C‐indices could be found for mStage compared with TNM stage in both development (0.750 vs 0.727) and validation cohorts (0.682 vs 0.646). Besides, patients with mStage A and B diseases could not benefit from adjuvant chemotherapy, while in patients with mStage C‐F diseases, those receiving radical surgery plus adjuvant chemotherapy presented better CSS than those with radical surgery alone. Conclusions The mStage system could predict the prognosis of colon cancer patients with LNE < 12 accurately and showed superior predictive power compared with conventional TNM staging system. Moreover, adjuvant chemotherapy might play inequable roles in patients with different mStage diseases.

Whether natural orifice specimen extraction surgery (NOSES) could provide beneficial effects in treating elderly patients is still under debate. The aim of the study was to compare the clinical outcomes of transanal NOSES with conventional laparoscopic-assisted resection (LA) in elderly colorectal cancer (CRC) patients. A retrospective analysis from the Second Affiliated Hospital of Harbin Medical University between 2013 and 2017 was performed. Outcomes related to surgery, body image, quality of life, anal function and long-term survival were compared between the two groups with the propensity-score matching (PSM) method. After PSM, 78 patients were successfully compared. Patients with NOSES had faster gastrointestinal function recovery (P = 0.028), less postoperative complications (P = 0.025), lower pain scores on days 1, 3 and 5 after surgery (P < 0.001). The body image score (P < 0.001) and cosmetic score (P < 0.001) were significantly higher in the NOSES group than the LA group at 1 month after surgery. Patients with NOSES posed better global health status (P < 0.001), role function (P = 0.009), emotional function (P = 0.011) and social function (P = 0.011) at 3 months after surgery. Moreover, NOSES showed non inferiority in anal function 6 months after surgery. No significant difference could be found regarding to overall survival (OS), disease-free survival (DFS), local recurrence (LR) and distant metastasis (DM). In elderly CRC patients, NOSES harbored favorable postoperative outcomes, excellent cosmetic properties and better quality of life. Besides, anal function and long-term outcomes of NOSES can be sure for elderly patients.

Purpose The purpose of this study was to explore the risk factors for synchronous liver metastasis (LM) of colorectal cancer (CRC) and to construct a nomogram for predicting the occurrence of synchronous LM based on baseline and pathological information. Methods The baseline and pathological information of 3190 CRC patients were enrolled in the study from the Department of Colorectal Surgery, the Second Affiliated Hospital of Harbin Medical University between 2012 and 2020. All patients were divided into development and validation cohorts with the 1:1 ratio. The characters of LM and none-LM patients in newly diagnosed colorectal cancer were utilized to explore the risk factors for synchronous LM with the univariate and multivariate logistic regression analyses. A predictive nomogram was constructed by using an R tool. In addition, receiver operating characteristic (ROC) curves was calculated to describe the discriminability of the nomogram. A calibration curve was plotted to compare the predicted and observed results of the nomogram. Decision-making curve analysis (DCA) was used to evaluate the clinical effect of nomogram. Results The nomogram consisted of six features including tumor site, vascular invasion (VI), T stage, N stage, preoperative CEA, and CA-199 level. ROC curves for the LM nomogram indicated good discrimination in the development (AUC = 0.885, 95% CI 0.854–0.916) and validation cohort (AUC = 0.857, 95% CI 0.821–0.893). The calibration curve showed that the prediction results of the nomogram were in good agreement with the actual observation results. Moreover, the DCA curves determined the clinical application value of predictive nomogram. Conclusions The pathologic-based nomogram could help clinicians to predict the occurrence of synchronous LM in postoperative CRC patients and provide a reference to perform appropriate metastatic screening plans and rational therapeutic options for the special population.

Exploring a modified stage (mStage) for pN0 colon cancer patients. 39,637 pN0 colon cancer patients were collected from the SEER database (2010–2015) (development cohort) and 455 pN0 colon cancer patients from the Second Affiliated Hospital of Harbin Medical University (2011–2015) (validation cohort). The optimal lymph nodes examined (LNE) stratification for cancer-specific survival (CSS) was obtained by X-tile software in the development cohort. LNE is combined with conventional T stage to form the mStage. The novel N stage was built based on the LNE (N0a: LNE ≥ 26, N0b: LNE = 11–25 and N0c: LNE ≤ 10). The mStage include mStageA (T1N0a, T1N0b, T1N0c and T2N0a), mStageB (T2N0b, T2N0c and T3N0a), mStageC (T3N0b), mStageD (T3N0c, T4aN0a and T4bN0a), mStageE (T4aN0b and T4bN0b) and mStageF (T4aN0c and T4bN0c). Cox regression model showed that mStage was an independent prognostic factor. AUC showed that the predictive accuracy of mStage was better than the conventional T stage for 5-year CSS in the development (0.700 vs. 0.678, P < 0.001) and validation cohort (0.649 vs. 0.603, P = 0.018). The C-index also showed that mStage had a superior model-fitting. Besides, calibration curves for 3-year and 5-year CSS revealed good consistencies between observed and predicted survival rates. For pN0 colon cancer patients, mStage might be superior to conventional T stage in predicting the prognosis.

Purpose: Distant metastasis (DM) is relatively rare in T1 colon cancer (CC) patients, especially in those with negative lymph node metastasis. The aim of this study was to explore the main clinical factors and build nomogram for predicting the occurrence and prognosis of DM in T1N0 colon cancer patients. Methods: Patients with T1N0 stage CC were collected from the Surveillance, Epidemiology, and End Result (SEER) database. All patients were divided into development and validation cohorts with the 3:1 ratio. Logistic regressions were performed to analyze the clinical risk factors for DM. Cox regression model was used to identify potential prognostic factors for patients with DM. The performance of nomogram was evaluated by concordance index (C-index), calibration curves, receiver operating characteristic (ROC) curves and decision curve analyses (DCAs). Based on cancer-specific survival (CSS), Kaplan-Meier curves were generated and analyzed using Log rank tests. Results: A total of 6770 patients were enrolled in this study, including 428 patients (6.3%) with DM. Age, size, grade, CEA were independent risk factors associated with DM. Age, grade, CEA, surgery and chemotherapy were independent prognostic factors for CSS. Nomograms were applied and C-index, calibration curves, ROC curves and DCA curves proved good discrimination, calibration and clinical practicability of the nomogram in predicting the occurrence and prognosis of DM in T1N0 CC patients. In the DM nomogram, the AUCs for development and validation cohort were 0.901 (95% CI = 0.879-0.922) and 0.899 (95% CI=0.865-0.940), respectively. The calibration curves (development cohort: S: p = 0.712; validation cohort: S: p = 0.681) showed the relatively satisfactory prediction accuracy. Similarly, the AUCs of the nomogram at 1-, 2-, and 3-year were 0.763 (95% CI=0.744-0.782), 0.794 (95% CI=0.775-0.813), and 0.822 (95% CI=0.803-0.841) for the development cohort, and 0.785 (95% CI=0.754-0.816), 0.748 (95% CI=0.717-0.779) and 0.896 (95% CI=0.865-0.927) for the validation cohort in the CSS nomogram. The C-indices of the development and validation cohort were 0.718 (95% CI=0.639-0.737) and 0.712 (95% CI=0.681-0.743). Conclusion:The population-based nomogram could help clinicians predict the occurrence and prognosis of DM in T1N0 CC patients and provide a reference to perform appropriate metastatic screening plans and rational therapeutic options for the special population.