Comparison of Right-side and Left-side Colon Cancers Following Laparoscopic Radical Lymphadenectomy

Development and validation of prognostic nomograms for early-onset colon cancer in different tumor locations: a population-based study

OBJECTIVE

The prevalence of early-onset colon cancer (EOCC) among individuals below the age of 50 has shown a marked upward trend in recent years. The embryology, clinical symptoms, incidence, molecular pathways, and oncologic outcomes differ between right-sided and left-sided colon cancers. However, the differences have not been fully researched in EOCC. Our study aims to develop and validate prognostic nomograms predicting overall survival (OS) and cancer-specific survival (CSS) for EOCC in different tumor locations based on the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Using the SEER database, a total of 5,588 patients with EOCC were extracted and divided into development and validation cohorts in a random allocation ratio of 7:3 across three groups. Univariate and multivariate Cox regression analyses were performed to identify independent prognostic factors influencing OS and CSS outcomes. These factors were then utilized to construct nomogram models. The prognostic capabilities of the three models were assessed through various evaluation metrics, including the concordance index (C-index), receiver operating characteristic (ROC) curves, calibration curves, decision curve analysis (DCA), and validation cohorts respectively. Additionally, survival curves of the low- and high-risk groups were calculated using the Kaplan-Meier method together with the log-rank test.

RESULTS

Significant differences in clinical features were observed between right-sided and left-sided EOCCs, particularly in terms of OS (52 months vs 54 months) as demonstrated by Kaplan-Meier curves. Transverse-sided EOCCs exhibited clinical characteristics similar to right-sided EOCCs, suggesting a potential shared tumor microenvironment and therapeutic considerations. Advanced stage, liver metastasis, poor grade, elevated pretreatment carcinoembryonic antigen (CEA) level, chemotherapy, and perineural invasion were identified as independent prognostic factors across all three tumor locations and were incorporated into the nomogram model. Nomograms were constructed to predict the probability of 3- and 5-year OS and CSS. The C-index and calibration plots showed that the established nomograms had good consistency between actual clinical observations and predicted outcomes. ROC curves with calculated area under the curve (AUC) values exceeded 0.8 for all three groups in both the development and validation cohorts, indicating robust predictive performance for OS and CSS. Furthermore, decision curve analysis (DCA) plots revealed a threshold probability range of 0.1 to 0.9, within which the nomogram model exhibited maximum benefit. Kaplan-Meier curves exhibited significant differences between the low- and high-risk groups in EOCC for all three tumor locations in OS and CSS, further validating the prognostic value of the nomogram models.

CONCLUSIONS

We successfully developed three precise nomogram models for EOCCs in different tumor locations, providing valuable support for clinicians in guiding clinical treatments and facilitating further prospective follow-up studies.

The Incidence and Prognosis Value of Perineural Invasion in Rectal Carcinoma: From Meta-Analyses and Real-World Clinical Pathological Features

AIMS

Perineural invasion (PNI) is a special type of metastasis of several cancers and has been reported as being a factor for poor prognosis in colorectal carcinoma. However, investigations of PNI in only rectal cancer and a comprehensive analysis combining meta-analyses with real-world case studies remain lacking.

MATERIALS AND METHODS

First, articles from 2000 to 2020 concerning the relationship between PNI and rectal cancer prognoses and clinical features were meta-analysed. Subsequently, we carried out a retrospective analysis of 312 rectal cancer cases that underwent radical surgery in the real world. The incidence of PNI and the relationship between PNI and prognosis, as well as clinicopathological factors, were investigated.

RESULTS

The incidence of PNI was 23.09% and 33.01% in the meta-analysis and clinical cases, respectively. PNI occurred as early as stage I (2.94%). Moreover, neoadjuvant therapy significantly reduced the PNI-positive rate (20.34% versus 26.54%). Both meta-analysis and real-world clinical case studies suggested that PNI-positive patients had poorer prognoses than PNI-negative patients. We established an effective risk model consisting of T stage, differentiation and lymphovascular invasion to predict PNI in rectal cancer.

CONCLUSION

PNI is a poor prognostic factor for rectal cancer and could occur even in stage I. Additionally, neoadjuvant therapy could sufficiently reduce the PNI-positive rate. T stage, lymphovascular invasion and differentiation grade were independent risk factors for PNI and the risk model that included these factors could predict the probability of PNI.

Long-term Oncological Results After Laparoscopic Sigmoidectomy for Adenocarcinoma

Purpose: Sigmoidectomy is performed in most cases for benign pathologies and mainly in cases of diverticulitis. Few studies in the literature report oncological results after sigmoidectomy for adenocarcinoma. The aim of this study was to report the long-term oncological outcomes after elective laparoscopic sigmoidectomy (LS) for adenocarcinoma. Methods: This study is a retrospective analysis of prospectively collected data. From January 2003 to February 2021, 173 patients underwent elective LS for adenocarcinoma. Twenty-four patients with a diagnosis of preoperative distant metastases were excluded (13.9%). Results: Seven postoperative complications were observed (7.1%). Of these, 2 (2%) anastomotic leakages were treated surgically by the Hartmann procedure (Clavien-Dindo grade III-b). The mean number of harvested lymph nodes with the specimen was 14.2 ± 7.1. At a median follow-up of 115 months (interquartile range 133.8), 2 (2%) and 9 patients (9.2%) had developed recurrence and metastases, respectively. During follow-up, 6 patients (6.1%) with metastases died due to disease progression and 6 other patients (6.1%) died due to causes other than cancer related. At the 5- and 10-year follow-ups, the overall survival rates were 90.5% ± 3.4% and 83.8% ± 4.5%, respectively, while the disease-free survival rates were 87.1% ± 4.1% and 83.5% ± 4.7%, respectively. Conclusion: LS is a safe and feasible technique both in terms of the number of harvested lymph nodes and oncological results. The possibility of sparing the colon without mobilizing the splenic flexure and dividing the left colic artery could reduce intra- and postoperative complications. Further studies with larger samples of patients are required to confirm these data.

Fucosyltransferase 4 Predicts Patient Outcome in Rectal Cancer through an Immune Microenvironment-Mediated Multi-Mechanism

Colorectal cancer is the most common type of gastrointestinal malignant tumors worldwide. Standardization of the strategy for the precise treatment of this cancer has been a major challenge. Enrichment analysis of six gene groups (colon cancer-specific genes (upregulated and downregulated); rectal cancer-specific genes (upregulated and downregulated); and common genes (upregulated and downregulated)) revealed the common and specific features of colon and rectal cancer, particularly a hyperactive immune response in rectal cancer. Key common genes exhibited a similar expression pattern, but were associated with distinct patient prognosis in colon and rectal cancer. FUT4 was a core regulatory gene in rectal cancer; it can decrease the level of infiltration by M2 macrophages in the tumor immune microenvironment and participate in the positive regulation of the immune system and glycoprotein biosynthetic process, thereby affecting the outcome of patients with rectal cancer. FUT4 co-expression genes can influence patient’s survival time by regulating the cell cycle. Among the regulators of FUT4 co-expression genes, checkpoint kinase 2 (CHEK2) was linked to patient outcome.

Outcomes of right-sided and left-sided colon cancer after curative resection

The right and left side of the colon derived from the midgut and hindgut, respectively. Previous studies have reported different characteristics of right-sided colon cancer (RCC) and left-sided colon cancer (LCC), but oncological outcomes remain unclear. This study compared the outcomes of RCC and LCC. This retrospective study included 1017 patients who received curative colectomy for stage I-III colon cancer at a single institute between August 2008 and December 2019. Overall survival (OS) and time to recurrence (TTR) were analyzed as outcome measurements. No significant difference in the OS or TTR of patients with RCC and LCC were observed. In subgroup analysis, RCC was associated with shorter TTR than LCC in stage II colon cancer (HR 2.36, 95% confidence interval 1.24–4.48, p < 0.01). Multivariate analysis demonstrated that right sidedness, R1 resection, low body mass index (BMI) and adjuvant chemotherapy were independent factors for poor prognosis for stage II colon cancer. Low BMI, perineural invasion, higher T stage and N2 stage were independent factors for poor prognosis for stage III colon cancer. The results were confirmed by multivariate analysis after propensity score matching. Our study revealed that RCC was an independent risk factor for recurrence in stage II colon cancer.

Value of MSCT plus MRI in the Detection of Colon Cancer

Colon cancer is a common digestive system malignancy with nonspecific early symptoms, which necessitates better early detection methods. The present study was conducted to assess the accuracy and clinical value of multislice spiral CT (MSCT) plus magnetic resonance imaging (MRI) for colon cancer. Between January 2019 and July 2020, 100 patients with pathologically confirmed colon cancer treated in Wuxi People's Hospital were assessed for eligibility and recruited. All eligible patients received MRI and MSCT without any treatment prior to scanning. The accuracy of preoperative diagnosis and staging of colon cancer by MRI, MSCT, and MRI plus MSCT were analyzed using postoperative pathological results as the gold standard, and consistency analysis was performed. The receiver operating characteristic curve (ROC) was plotted, and the area under the curve (AUC) was obtained to analyze the preoperative diagnostic value. The accuracy of MRI, MSCT, and MRI plus MSCT was 98.00%, 96.00%, and 100% with good consistency (Kappa = 0.732, 0.703, and 0.756). The AUC of MRI, MSCT, and MRI plus MSCT was 0.889, 0.861, and 0.903, respectively. The preoperative diagnostic accuracy of MRI for colon cancer at T1, T2, T3, and T4 stages was 76.92%, 82.61%, 73.47%, and 86.67%, respectively, those of MSCT was 53.85%, 69.57%, 63.27%, and 40.00%, respectively, and those of MRI plus MSCT was 100.00%, 95.65%, 95.92%, and 86.67%, respectively. Consistency analysis yielded good consistency for the diagnosis of the T-staging of colon cancer (Kappa = 0.754, 0.731, 0.776). MSCT plus MRI yielded higher accuracy, specificity, and sensitivity in the detection of colon cancer versus the standalone MRI or MSCT, which demonstrated great potential in the early detection of colon cancer with a high clinical value.

Differences in the On- and Off-Tumor Microbiota between Right- and Left-Sided Colorectal Cancer

This study aims to determine differences in the on- and off-tumor microbiota between patients with right- and left-sided colorectal cancer. Microbiome profiling of tumor and tumor-adjacent biopsies from patients with right-sided (n = 17) and left-sided (n = 7) colorectal adenocarcinoma was performed using 16S ribosomal RNA sequencing. Off-tumor alpha and beta diversity were significantly different between right- and left-sided colorectal cancer patients. However, no differences in on-tumor diversity were observed between tumor locations. Comparing the off-tumor microbiota showed the right colon to be enriched with species of the Lachnoclostridium, Selenomonas, and Ruminococcus genera. Whereas the left colon is enriched with Epsilonbacteraeota phylum, Campylobacteria class, and Pasteurellales and Campylobacterales orders, in contrast, the on-tumor microbiota showed relatively fewer differences in bacterial taxonomy between tumor sites, with left tumors being enriched with Methylophilaceae and Vadin BE97 families and Alloprevotella, Intestinibacter, Romboutsia, and Ruminococcus 2 genera. Patients with left-sided colorectal cancer had large taxonomic differences between their paired on- and off-tumor microbiota, while patients with right-sided colorectal cancer showed relatively fewer taxonomic differences. Collectively, this suggests that the right and left colon show distinctive bacterial populations; however, the presence of a colonic tumor leads to a more consistent microbiota between locations.