Contemporary colorectal cancer (CRC) epidemiology reveals evolving risk factors have reconfigured CRC as a societally-modulated, quasi-age-dependent disease. Nevertheless, temporal drivers of incidence/incidence-based mortality (IBM) patterns and longitudinal trends in clinicopathological profiles, therapeutic modalities, and 5-year survival (5-YS) remain incompletely defined, necessitating methodologically rigorous studies. The Surveillance, Epidemiology, and End Results Program data (1975-2019) were analyzed using the National Cancer Institute's (NCI's) Age-Period-Cohort Analysis Tool to examine temporal drivers of US CRC epidemiology. Longitudinal trends in clinicopathological profiles, therapeutic modalities, and 5-YS were further assessed via NCI's Joinpoint Regression Program. The relative risk (RR) of incidence increased exponentially in sequentially younger birth cohort, with the annual percentage change (APC) peaking at 6.11% in 20 - 24 years, while the RR of IBM declined in successively older birth cohorts and showed no improvement in younger birth cohorts. Early-onset CRC with regional- or distant-predominant disease (notably hepatic) showed a marked shift from adjuvant to neoadjuvant therapy, including a notable increase in preoperative radiotherapy for regional rectal cancer from 19.7% (2000) to 53.8% (2019), and preoperative systemic therapy for distant colon cancer from 5.5% (2007) to 17.6% (2019). Correspondingly, stage-specific 5-YS was also superior in early-onset CRC (e.g., regional rectal cancer: 82.5% vs. 67.8%; distant colon cancer: 22.9% vs. 14.7%), with greater annual improvement (e.g., APC for regional rectal cancer: 1.60% vs. 1.46%; APC for distant colon cancer: 3.59% vs. 2.55%). However, over 50% of distant metastatic patients, especially those with late-onset disease, still received no effective treatment. While overall CRC burden decreased in the US, extreme early-onset CRC surged with poor prognosis. Despite higher regional/metastatic burden, early-onset CRC showed better survival owing to aggressive treatment and adherence. Urgent actions are needed to address the rising risk in youth and therapeutic gaps in metastatic disease.

Background: Current evidence suggests that neoadjuvant chemoradiotherapy (nCRT) followed by total mesorectal excision (TME) alone is insufficient for magnetic resonance imaging (MRI)–suspected lateral lymph node metastasis (LLNM) in rectal cancer. However, whether upfront TME with lateral lymph node dissection (LLND) is adequate, and whether adding nCRT before planned LLND confers additional benefit, remains controversial. Methods: Between May 2021 and September 2022, a total of 342 patients from 20 Chinese centers were enrolled, of whom 293 were included in the final analysis and received either long-course nCRT plus TME with LLND or upfront TME+LLND. Groups were balanced by propensity score matching. The primary endpoint was 3-year recurrence-free survival (RFS). Findings: After matching, the nCRT group had significantly better 3-year RFS (HR 0.54; 95% CI. 0.32–0.92; P=0.023) and locoregional recurrence-free survival (HR 0.37; 95% CI, 0.19–0.74; P=0.005); distant metastasis-free survival did not differ (HR 0.74; 95% CI, 0.37–1.47; P=0.385). In patients with pretreatment positive lateral nodes (n=141), nCRT also improved RFS (HR 0.53; 95% CI, 0.28–0.99; P=0.049) and local control (HR 0.35; 95% CI, 0.15–0.77; P=0.010). Pathologic complete response in lateral nodes after nCRT was 44.7% (34/76). Overall postoperative complication rates were similar between groups (19.8% vs 16.0%; P=0.474), as were severe complications (grade III–V, 9.4% vs 8.5%; P=0.811). Interpretation: In MRI-suspected LLNM, adding nCRT to TME with LLND significantly improves RFS and local control without increasing morbidity. Upfront surgery alone is insufficient. These findings support a combined treatment paradigm and confirm the necessity of nCRT in these patients.

Multiple primary colorectal cancer (MPCRC) is uncommon but clinically challenging, and differences between synchronous MPCRC (SMPCRC) and metachronous MPCRC (MMPCRC) remain incompletely defined. We compared clinicopathological and surgical features between SMPCRC and MMPCRC and explored prognostic factors for overall survival (OS) in MPCRC. This retrospective cohort study consecutively included patients with pathologically confirmed multiple primary colorectal adenocarcinoma who underwent curative-intent resection at our hospital. SMPCRC was defined as tumors identified within 6 months and MMPCRC as a subsequent primary diagnosed after 6 months. Clinicopathological and perioperative variables were extracted from medical records and pathology reports. Mismatch repair protein expression was assessed as an exploratory pathological variable. OS was analyzed using Kaplan–Meier methods and Cox proportional hazards regression. A total of 165 patients were included (120 SMPCRC and 45 MMPCRC) with follow-up until December 2024. Baseline characteristics were broadly comparable between groups. SMPCRC more frequently underwent laparoscopic surgery (97.5

Purpose: This study aimed to determine the optimal temporal threshold for distinguishing "early" from "late" liver metastasis in patients who developed liver metastasis after colorectal cancer (CRC) surgery, and to evaluate whether KRAS and BRAFV600E mutations, along with other clinicopathological factors, are associated with the timing of liver metastasis. Methods: This retrospective study utilized clinical and pathological data from patients who developed liver metastasis after radical CRC surgery at two centers from 2019 to 2023. X-tile software was used to identify the optimal temporal threshold. Logistic regression analysis was applied to determine if KRAS/BRAFV600E mutations and other potential factors are independently associated with the time to onset of liver metastasis. Results: X-tile analysis identified 11 months post-surgery as the optimal cutoff for distinguishing early metachronous liver metastasis (EMLM) from late metachronous liver metastasis (LMLM), classifying 114 cases into the EMLM group and 72 into the LMLM group. Comparative analysis indicated statistically significant differences between the two groups in lymphovascular tumor emboli, perineural invasion, and postoperative adjuvant therapy (p < 0.05). Logistic regression analysis revealed that neither KRAS mutation (OR, 1.185; 95% CI: 0.641-2.190; p = 0.587) nor BRAFV600E mutation (OR, 2.836; 95% CI: 0.302-26.642; p = 0.363) was independently associated with the timing of liver metastasis. In contrast, postoperative adjuvant therapy showed a statistical association with a likelihood of LMLM (OR, 0.253; 95% CI: 0.105-0.611; p = 0.002). Conclusions: This study identified 11 months post-CRC surgery as the optimal cutoff for differentiating EMLM versus LMLM. In this cohort, no statistically significant association was observed between KRAS/BRAFV600E mutations and the timing of liver metastasis, whereas postoperative adjuvant therapy was statistically correlated with the likelihood of LMLM. This stratification may guide personalized surveillance strategies and provide valuable insights for future mechanistic investigations into the temporal heterogeneity of post-surgical liver metastasis. However, the interpretation and generalization of the findings require external validation in prospective cohorts.

One of the most important changes in the transformation of normal cells into tumor cells is metabolism. In order to satisfy the more active proliferation, migration and metastasis of cancer cells, abnormal changes occur in various pathways and molecules involved in metabolism, which eventually lead to metabolic reprogramming of tumor cells. This process involves the uptake of nutrients and changes in major metabolic forms. As an important part of post-transcriptional epigenetics, RNA methylation modifications can regulate RNA processing and metabolism, while dynamically and reversibly influencing the expression of specific molecules, thereby ultimately affecting diverse biological processes and cellular phenotypes. In this review, various types of RNA methylation modifications involved in cancer are summarized. Subsequently, we systematically elucidate the mechanism of RNA modification for metabolic reprogramming in cancer, including glucose, lipid, amino acid and mitochondrial metabolism. Most importantly, we discuss in depth the clinical significance of RNA modification in metabolic targeted therapy and immunotherapy from mechanism to therapeutic application.

Background:Colorectal cancer (CRC) remains a leading global malignancy with a rising obesity-attributable burden. Emerging evidence highlights concerning trends in early-onset CRC and marked regional disparities, underscoring the need for comprehensive epidemiological assessments to inform targeted prevention strategies. Methods:Using Global Burden of Disease 2023 data, we analysed high body mass index (BMI)-related CRC deaths and disability-adjusted life years (DALYs) among adults (>40 years) from 1990-2023. We analysed both absolute counts and age-standardised rates, stratifying by sex, age, region, and sociodemographic index (SDI) categories. Decomposition analysis quantified the contributions of ageing, population growth, and epidemiological factors. We used Bayesian age-period-cohort analysis to project future trends. Results:From 1990 to 2023, the global number of high BMI-related CRC deaths increased more than 2-fold, accompanied by a corresponding marked increase in DALYs. Western Europe had the highest burden, while South Asia had the most rapid growth in deaths, as measured by the estimated annual percentage change. Generally, as SDI decreased, the corresponding numbers of deaths and DALYs decreased. Cluster analysis based on the estimated annual percentage changes in age-standardised rates of high BMI-related CRC deaths and DALYs identified distinct regional patterns, with significant decreases in these rates in Western Europe and high-income North America, contrasted by significant increases in South Asia and Central Sub-Saharan Africa. Decomposition analysis indicated that population growth was the primary driver of the rise in mortality, followed by population ageing, and these were partially offset by improvements in epidemiological risk. Projections suggest a continuing increase in the age-standardised death rates for both males and females by 2038. Conclusions:High BMI has become a key driver of CRC mortality and incidence worldwide. Reducing this burden requires efforts in healthy lifestyles, policy reforms, and international scientific cooperation.

Background:Repetitive elements account for a large proportion of the human genome and undergo alterations during early tumorigenesis. However, the exclusive fragmentation pattern of DNA-derived cell-free repetitive elements (cfREs) remains unclear. Methods:This study enrolled 32 healthy volunteers and 112 patients with five types of cancer. A novel repetitive fragmentomics approach was proposed to profile cfREs using low-pass whole genome sequencing (WGS). Five innovative repetitive fragmentomic features were designed: fragment ratio, fragment length, fragment distribution, fragment complexity, and fragment expansion. A machine learning-based multimodal model was developed using these features. Results:The multimodal model achieved high prediction performance for early tumor detection, even at ultra-low sequencing depths (0.1×, AUC = 0.9824). Alu and short tandem repeat (STR) were identified as the primary cfREs after filtering out low-efficiency subfamilies. Characterization of cfREs within tumor-specific regulatory regions enabled accurate tissue-of-origin (TOO) prediction (0.1×, accuracy = 0.8286) and identified aberrantly transcribed tumor driver genes. Conclusion:This study highlights the abundance of repetitive DNA in plasma. The innovative fragmentomics approach provides a sensitive, robust, and cost-effective method for early tumor detection and localization.

Background Lateral lymph node dissection (LLND) is a key component of surgical treatment for locally advanced mid-to-lower rectal cancer. While indocyanine green (ICG) fluorescence guidance has been proposed to enhance surgical precision, its impact on long-term oncological outcomes remains unclear. Methods This retrospective, multicenter study compared ICG-assisted laparoscopic LLND (ICG-LND) with conventional laparoscopic LLND in patients with mid-to-lower rectal cancer between January 2018 and June 2022. Outcomes included 3-year overall survival (OS), recurrence-free survival (RFS), local recurrence rates, and distant metastasis rates. Kaplan-Meier analysis and Cox proportional hazards regression models were used to evaluate survival outcomes. Results The study included 258 patients (ICG-LND: 79; control: 179). The ICG-LND group had a slightly higher median number of harvested lateral lymph nodes (9 [IQR: 5–13] vs. 7 [IQR: 4–13]), but the difference was not significant (P = 0.611). Similarly, positive lateral lymph node counts showed no significant difference (P = 0.455). Median postoperative hospital stays were shorter in the ICG-LND group (6 [IQR: 5–8] vs. 7 [IQR: 6–9] days, P < 0.001). Survival analysis showed no significant differences between groups in OS (5-year: 84.6% vs. 86.1%, P = 0.884), RFS, or recurrence rates (local: 6.3% vs. 6.7%; distant: 10.1% vs. 10.8%). Conclusion ICG-LND shortens postoperative recovery but does not enhance long-term oncological outcomes, including survival and recurrence rates. Further prospective studies are needed to validate its prognostic value.

To explore the application effect of the technique of “priority dissecting of the inferior mesenteric artery combined with complete medial approach (IMA-CMA)” in laparoscopic left-sided colon cancer radical resection. A total of 99 patients who underwent laparoscopic left-sided colon cancer radical resection with splenic flexure mobilization between September 2021 to May 2023 were included. Sixty-eight of these patients were analyzed after propensity score matching (PSM). The perioperative characteristics were compared. Among these enrolled patients, 45 underwent the traditional approach, and 54 underwent IMA-CMA approach. After PSM, the patients were matched to include 34 patients in each group, with no significant differences in the sex (p = 0.618) or location of tumor (p = 0.798) between the two groups. The patients in IMA-CMA group had shorter operating time (p = 0.032), less intraoperative blood loss (p = 0.003), a higher number of harvested lymph nodes (p = 0.044) and center group lymph nodes(p = 0.037), and a shorter postoperative hospital stay (p = 0.011). Number of positive lymph nodes and postoperative complications were not significantly different between the two groups. The technique of IMA-CMA for splenic flexure mobilization is safe and feasible. It can reduce operating time, intraoperative blood loss and postoperative hospital stay, which is conducive to achieving a thorough D3 lymphadenectomy without increasing the incidence of perioperative complications.

PurposeThis study aimed to analyze the risk factors and survival prognosis of local recurrence in stage II-III colorectal cancer (CRC) and develop a clinical risk calculator and nomograms to predict local recurrence and survival in treated patients.MethodsPatients who underwent radical surgery between January 2009 and December 2019 at the China National Cancer Center were included. Multivariate nomograms and a clinical risk calculator based on Cox regression were developed. Discrimination was measured with an area under curve (AUC) and variability in individual predictions was assessed with calibration curves. We stratified patients into different risk groups according to the established model to predict their prognosis and guide clinical practice.ResultsThe clinical risk calculator incorporated six variables: tumor thrombus, perineural invasion, tumor grade, pathology T-stage, pathology N-stage, and whether more than 12 lymph nodes were harvested. Our clinical risk calculator provided good discrimination, with AUC values of local recurrence-free survival (LRFS) (0.764) and overall survival (OS) (0.815) in the training cohort and LRFS (0.740) and OS (0.730) in the test cohort. Calibration plots illustrated excellent agreement between the clinical risk calculator predictions and actual observations for 3- and 5-year LRFS and OS. Recurrence risk-stratified analysis showed that low-risk patients were more likely to undergo salvage radical surgery when recurrent disease existed.ConclusionThe clinical calculator can better account for tumor and patient heterogeneity, providing a more individualized outcome prognostication. The model is expected to aid in treatment planning, such as resectability evaluation, and it can be used in postoperative surveillance (https://oldcoloncancer.shinyapps.io/dynnomapp/).

Local advanced rectal cancer (LARC) carries high recurrence risks, especially with lateral lymph node (LLN) involvement. This study aims to evaluate the role of ICG-guided sentinel lymph node biopsy (SLNB) in patients with clinical negative LLNs (maximum diameter < 7 mm), potentially reducing unnecessary surgeries and associated complications in patients with LARC. A retrospective analysis of 301 consecutive patients with lower LARC who underwent fluorescent lateral pelvic sentinel lymph node biopsy (FL-SLNB) or conventional LLND at the Cancer Hospital, Chinese Academy of Medical Sciences between 2018 and 2022 was conducted. Clinical and pathological data were collected, and the patients were grouped into FL-SLNB and non-SLNB groups. Postoperative complications, recurrence rates, and survival outcomes were assessed. Statistical analysis was performed using χ2 tests, Mann–Whitney U tests, Kaplan–Meier survival curves, and Cox proportional hazards models. FL-SLNB (173 patients) showed better perioperative outcomes than non-SLNB (128 patients), with shorter hospital stays (7 vs. 10 days, P = 0.027), less blood loss (150 vs. 180 mL, P = 0.032), and fewer complications: intraoperative bleeding (2.9

Anastomotic leakage (AL) is a serious complication in colorectal surgery, particularly after laparoscopic intersphincteric resection (LsISR) for ultra-low rectal cancer. This study evaluates the effectiveness of ICG fluorescence laparoscopic (FL) resection in reducing AL and improving recovery, especially in high-BMI patients. A retrospective cohort study was conducted on patients undergoing LsISR for ultra-low rectal adenocarcinoma from January 2012 to July 2023, comparing FL (n = 133) and non-FL groups (n = 266). The primary endpoint was the incidence of anastomotic leakage, including symptomatic AL. Secondary endpoints included intraoperative blood loss, lymph node yield, and short-term recovery parameters such as bowel function recovery, soft diet initiation, and hospital stay.Propensity score matching (PSM) was used to reduce baseline differences. In the PSM cohort, the FL group had a significantly lower AL rate (3.0

There have been previously reported associations between the gut microbiota, immune cells, and colorectal cancer; however, the specific mechanisms underlying these relationships remain largely unexplored and require further research. Therefore, in this study, we aimed to unravel the interactions between the gut microbiota, immune cells, and colorectal cancer. The analysis used genome-wide association study (GWAS) data encompassing 207 microbial taxa and 205 functional pathways and data on 731 immune cell phenotypes. Colorectal cancer data on 6 581 cases and 463 421 controls were sourced from the Integrative Epidemiology Unit Open GWAS Project. Univariate inverse-variance weighted Mendelian randomization analysis was used to identify gut microbial taxa associated with colorectal cancer. Mediation analysis was used to identify the mediating role of specific immune cells in the link between gut bacteria and colorectal cancer. Univariate inverse-variance weighted Mendelian randomization analysis revealed that several microbial taxa from the Actinobacteria and Firmicutes phyla were significantly associated with colorectal cancer. Coriobacteriaceae (odds ratio [OR]: 0.84, 95

BACKGROUND:Adjuvant chemotherapy is the standard management approach for patients with stage II/III colon cancer; however, the effectiveness in older patients is still unclear. This study aimed to explore the efficacy of adjuvant chemotherapy and whether oxaliplatin-based chemotherapy has better oncological outcomes than capecitabine monotherapy in older patients with stage III or high-risk stage II colon cancer. METHODS:We analyzed and compared oxaliplatin-based adjuvant chemotherapy with capecitabine monotherapy and non-adjuvant chemotherapy in 468 patients aged ≥70 years with stage III and high-risk stage II colon cancer, and a propensity score-matched analysis was conducted. The endpoints were overall survival (OS), cancer-specific survival (CSS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS). RESULTS:Multivariate analysis shows that adjuvant-treated stage III or high-risk stage II patients experienced a highly significant increase in OS (hazard ratio [HR]: 0.34, 95% confidence interval [CI]: 0.20-0.59, P <0.001) and CSS (HR: 0.39, 95% CI: 0.20-0.75, P = 0.005) compared with the control group without adjuvant chemotherapy. By contrast, no statistically significant difference was observed in either LRFS or DMFS (all P >0.05). The subgroup analysis suggested that no statistically significant benefits were observed between oxaliplatin-based adjuvant chemotherapy and capecitabine monotherapy, and no significant differences in oncological outcomes were detected with ≥6 months of therapy compared with 3-6 months (excluding 6 months) of therapy. CONCLUSION:Older patients with stage III or high-risk stage II colon cancer can benefit from adjuvant chemotherapy, and capecitabine monotherapy has non-inferior oncological outcomes compared with oxaliplatin-based regimens. CLINICAL TRIAL NUMBER:ClinicalTrials.gov , NCT04074538.

BACKGROUND:Diverting stoma (DS) is routinely proposed in intersphincteric resection for ultralow rectal cancer, but it is associated with increased stoma-related complications and economic burden. Appropriate patient selection and operative strategies to avoid stoma formation need further elucidation. AIM:To select patients who may not require DS. METHODS:This study enrolled 505 consecutive patients, including 84 who underwent stoma-free (SF) intersphincteric resection. After matching, patients were divided into SF (n = 78) and DS (n = 78) groups. The primary endpoint was the anastomotic leakage (AL) rate within 6 months and its protective factors for both the total and SF cohorts. The secondary endpoints included overall survival and disease-free survival. RESULTS:The AL rate was greater in the SF group than in the DS group (12.8% vs 2.6%, P = 0.035). Male sex [(odds ratio (OR) = 2.644, P = 0.021], neoadjuvant chemoradiotherapy (nCRT) (OR = 6.024, P < 0.001), and tumor height from the anal verge ≤ 4 cm (OR = 4.160, P = 0.007) were identified as independent risk factors. Preservation of the left colic artery (LCA) was protective in both the total cohort (OR = 0.417, P = 0.013) and the SF cohort (OR = 0.312, P = 0.027). The female patients who did not undergo nCRT and had preservation of the LCA experienced a significantly lower incidence of AL (2/97, 2.1%). The 3-year overall survival or disease-free survival did not significantly differ between the groups. CONCLUSION:Female patients who do not receive nCRT may avoid the need for DS by preserving the LCA without increasing the risk of AL or compromising oncological outcomes.

Objective This study aims to assess the necessity and outcomes of bilateral lateral lymph node dissection (LLND) in rectal cancer, while exploring the role of Indocyanine Green (ICG) in enhancing surgical precision. Methods A retrospective analysis was conducted on 157 patients who underwent LLND between January 1, 2010, and December 31, 2022. The study focused on the incidence of bilateral lymph node metastasis, the predictors of metastasis, and the role of ICG-guided dissection in improving surgical outcomes. Propensity score matching (PSM) was used to compare the outcomes between the control and fluorescence-guided lymph node dissection (FLND) groups. Results Bilateral lateral lymph node metastasis was found in 6.4 ​% of patients. Positive D2 lymph nodes were the only significant predictor of bilateral metastasis. ICG, used via submucosal injection, significantly improved lymph node identification and dissection accuracy. Patients in the FLND group had a higher median number of harvested lymph nodes (32 vs. 19, P ​= ​0.042) and better postoperative outcomes, including shorter hospital stay (6 vs. 9 days, P ​= ​0.038) and less blood loss (30 ​ml vs. 180 ​ml, P ​< ​0.001). Kaplan-Meier analysis showed no significant differences in disease-free survival (P ​= ​0.658) or overall survival (P ​= ​0.331) between groups. Conclusion While ICG-enhanced bilateral LLND improves short-term surgical outcomes, its impact on long-term survival remains unclear. The findings suggest selective use of bilateral LLND based on specific risk factors, particularly in patients with positive D2 lymph nodes. Further studies are required to refine guidelines and establish the procedure's long-term benefits.

To identify the clinical and molecular factors that effectively predict pathological complete response (pCR) and assess the safety of patients receiving neoadjuvant combination immunotherapy. This retrospective study evaluated 81 patients with colorectal cancer (CRC) at a Chinese tertiary center between 2015 and 2023. The cohort included 24 patients with deficient mismatch repair (dMMR) and 57 patients with proficient mismatch repair (pMMR) tumors. Patients were treated with a neoadjuvant combination of immunotherapy and surgery. We divided 81 patients into pCR (40.7

Background/Objectives: The metastatic patterns of apical lymph node (ALN) in rectal and sigmoid colon cancer are currently unclear, and there is no consensus on the indications for dissection of ALN. This study aimed to analyze the impact of ALN metastasis on prognosis, determine the metastatic patterns of ALN and provide evidence for indications of ALN dissection in rectal and sigmoid colon cancer. Methods: In this multicenter, retrospective cohort study, patients from five centers with stage I-III rectal or sigmoid colon cancer who underwent laparoscopic radical surgery with ALN dissection without neoadjuvant treatment from January 2015 to December 2019 were enrolled. Results: Among 2809 patients, the positive rate of ALN was 1.9%. The 5-year overall survival and cancer-specific survival rate for patients with metastatic ALN were 37.5% and 41.0%, respectively. ALN metastasis was the independent risk factor for poor prognosis. Tumor size ≥5 cm (OR = 2.32, 95% CI: 1.30–4.13, p = 0.004), signet ring cell cancer/mucinous adenocarcinoma (vs. poor differentiated adenocarcinoma, OR = 0.19, 95% CI: 0.08–0.45, p < 0.001; vs. moderate to well differentiated adenocarcinoma, OR = 0.22, 95% CI: 0.11–0.42, p < 0.001), T4 stage (OR = 1.93, 95% CI: 1.05–3.55, p = 0.034), N2 stage (OR = 8.86, 95% CI: 4.45–17.65, p < 0.001) and radiologic evidence of extramural venous invasion (OR = 1.88, 95% CI: 1.03–3.42, p = 0.040) were independent risk factors for ALN metastasis. The nomogram model developed by these factors achieved a good predictive performance. Conclusions: This research offered insights into the incidence, risk factors, and prognostic significance of apical lymph node metastasis in cases of rectal and sigmoid colon cancer. Additionally, the study furnished empirical support for the criteria guiding ALN dissection. Furthermore, a pragmatic risk assessment model was developed to predict ALN metastasis.

BACKGROUND:Characteristics and prognoses of lateral lymph node (LLN) metastasis but not mesenteric lymph node (LN) metastasis are poorly understood. This study explored patterns of mesenteric and LLN metastases in rectal cancer patients. METHOD:This retrospective, multicentre study was conducted at three institutions and included patients who underwent total mesorectal excision (TME) with lateral lymph node dissection (LLND) for rectal cancer (n = 271). RESULTS:Among the patients with LLN metastases, 210 patients (77.5 %) with clinical stage T3-4 disease and 157 patients (57.9 %) with clinical stage N1-N2 disease underwent TME as well as LLND. The prognoses of patients with metastasis confined to LLNs were significantly better than those of patients with both mesenteric and LLN metastases (3-year overall survival: 85.0 % vs. 51.0 %, p = 0.005; 3-year disease-free survival: 75.0 % vs. 26.5 %, p = 0.003) and were similar to those of patients with metastasis confined to mesenteric LNs (3-year overall survival: 85.0 % vs. 83.8 %, p = 0.607; 3-year disease-free survival 75.0 % vs. 68.8 %, p = 0.717). Patients with metastases confined to LLN had a lower proportion of poor histological types (20.0 % vs. 65.3 %, p = 0.002), lymphatic invasion (20.0 % vs. 59.2 %, p = 0.036) and number of LLN metastases (1.6 vs 2.7, p = 0.004), and all metastases were confined to the internal iliac or obturator region (100.0 % vs. 77.6 %, p = 0.008) compared to patients with both mesenteric and LLN metastasis. CONCLUSIONS:Approximately a quarter of patients with rectal cancer have LLN metastases but no mesenteric LN metastases. These patients have favourable pathological features and prognoses and can be managed and treated for mesenteric LN metastasis.

BACKGROUND:Colorectal cancer (CRC) patients with stage pT4b are a complex group as they show differences in tumor-infiltrated organs. Patients with the same stage often exhibit differences in prognosis after multivisceral resection (MVR). Thus far, some important prognostic factors have not been thoroughly investigated. Here, we identified the prognostic factors influencing CRC patients at the pT4bN0M0 stage to stratify the prognostic differences among patients. MATERIALS AND METHODS:A retrospective analysis was conducted on patients diagnosed with locally advanced CRC and who underwent MVR at three medical institutions from January 2010 to December 2021. The prognostic factors affecting the survival of CRC patients at pT4bN0M0 stage were identified by multivariate Cox proportional hazard models. We then classified the prognosis into different grades on the basis of these independent prognostic factors. RESULTS:We enrolled 690 patients with locally advanced CRC who underwent MVR; of these, 172 patients with pT4bN0M0 were finally included. Patients with digestive system [overall survival (OS): hazard ratio (HR)=0.441; 95% confidence interval (CI)=0.217-0.900; P =0.024; disease-free survival (DFS): HR=0.416; 95% CI=0.218-0.796; P =0.008) or genitourinary system invasion (OS: HR=0.405; 95% CI=0.193-0.851; P =0.017; DFS: HR=0.505; 95% CI=0.267-0.954; P =0.035) exhibited significantly better OS and DFS as compared to those with gynecological system invasion, while the OS and DFS were similar between the digestive system and genitourinary system invasion groups (OS: HR=0.941; 95% CI=0.434-2.042; P =0.878; DFS: HR=1.211; 95% CI=0.611-2.403; P =0.583). Multivariate analysis showed that age (OS: HR=2.121; 95% CI=1.157-3.886; P =0.015; DFS: HR=1.869; 95% CI=1.116-3.131; P =0.017) and type of organs invaded by CRC (OS: HR=3.107; 95% CI=1.121-8.609; P =0.029; DFS: HR=2.827; 95% CI=1.142-6.997; P =0.025) were the independent prognostic factors that influenced the OS and DFS of CRC patients with pT4bN0M0 disease. The OS and DFS of patients showing invasion of the gynecological system group were significantly worse ( P =0.004 and P =0.003, respectively) than those of patients with invasion of the nongynecological system group. On the basis of the above-mentioned two independent prognostic factors, patients were assigned to high-risk, medium-risk, and low-risk groups. Subgroup analysis showed that the OS and DFS of the medium-risk and high-risk groups were significantly worse ( P =0.001 and P =0.001, respectively) than those of the low-risk group. CONCLUSION:Patients with pT4bN0M0 CRC show significant differences in their prognosis. The type of organs invaded by CRC is a valuable indicator for prognostic stratification of CRC patients with pT4bN0M0.