Comparison of recurrence patterns between ≤5 years and >5 years after curative operations in colorectal cancer patients

Eyelid and Parotid Gland Metastasis of Colorectal Cancer Demonstrated by 18F-FDG PET/CT

A 67-year-old man underwent a sigmoid colectomy and received 4 cycles of capecitabine and oxaliplatin. 18F-FDG was performed for the treatment response evaluation. It revealed increased radiotracer uptake both in the nodular lesion of the left parotid gland and in the subcutaneous density of the left eyelid. These lesions were reported as colorectal carcinoma metastasis in immunohistochemical evaluation. Herein, we present an extremely rare case of simultaneous metastasis of both the eyelid and the left parotid gland in a patient who underwent surgery for colorectal cancer.

Localized Rectal Cancer: Indian Consensus and Guidelines

The rising incidence of colorectal cancer (CRC) in India, particularly the prevalence of rectal cancer over colon cancer (0.7:1), has been a growing concern in recent decades; especially notable is the trend of increasing cases among young CRC patients. Given the diverse treatment approaches for rectal cancer globally and the varying economic capacities of patients in low to middle-income countries (LMICs) like India, it is essential to establish consensus guidelines that are specifically tailored to meet the needs of these patients. To achieve this, a panel comprising 30 eminent rectal cancer experts convened to conduct a comprehensive and impartial evaluation of existing practices and recent advancements in the field. Through meticulous scrutiny of published literature and a consensus-building process that involved voting on pertinent questions, the panel formulated management strategies. These recommendations are the result of a rigorous, evidence-based process and encapsulate the collective wisdom and judgment of leading authorities in the field.

Developing Individualized Follow-Up Strategies Based on High-Risk Recurrence Factors and Dynamic Risk Assessment for Locally Advanced Rectal Cancer

BACKGROUND

Locally advanced rectal cancer (LARC) is one of the most common malignant tumors worldwide, and its incidence is increasing year by year. Despite multimodal treatment, the recurrence rate of LARC patients remains high, about 20%-50%. However, the follow-up strategy according to tumor stage has certain limitations. There is no consensus on the optimal frequency and duration of follow-up. This study aims to comprehensively analyze the high-risk factors for recurrence in LARC from clinical characteristics, nutritional indicators, and imaging indexes. It intends to utilize conditional survival (CS) evaluation to assess dynamic survival and recurrence risks after comprehensive treatment of LARC and to develop individualized follow-up strategies.

METHODS

Logistic regression was utilized to analyze the independent recurrence factors in LARC patients. Calibration curve, decision curve, and ROC curve were employed to evaluate the model's efficacy. Kaplan-Meier curve was used to calculate CS rate and compare survival differences among different risk groups.

RESULTS

A total of 561 patients were analyzed in our study. Our multivariable logistic regression analysis revealed that the prognostic nutritional index (PNI), extramural vascular invasion (EMVI), vascular tumor thrombus, perineural invasion, and tumor size were independent factors for recurrence. Subsequently, a nomogram model was constructed and risk stratification was performed. Calibration curves and decision curves demonstrated that the model exhibited good clinical efficacy. The area under the ROC curve for the model was 0.763, indicating good sensitivity and specificity. Kaplan-Meier curves showed significant differences in survival among different risk groups. Furthermore, we observed that the CS without local recurrence and distant metastasis increased each year, while the cumulative recurrence risk decreased annually with prolonged survival time. Tailored follow-up intensities were developed for different risk groups and clinical stages based on the cumulative recurrence risk.

CONCLUSION

The personalized follow-up strategy based on risk stratification can optimize resource allocation, early detection of recurrence or metastasis, and ultimately enhance the overall care and prognosis of LARC patients.

Identifying timing and risk factors for early recurrence of resectable rectal cancer: A single center retrospective study

BACKGROUND

Colorectal cancer is a common malignancy and various methods have been introduced to decrease the possibility of recurrence. Early recurrence (ER) is related to worse prognosis. To date, few observational studies have reported on the analysis of rectal cancer. Hence, we reported on the timing and risk factors for the ER of resectable rectal cancer at our institute.

AIM

To analyze a cohort of patients with local and/or distant recurrence following the radical resection of the primary tumor.

METHODS

Data were retrospectively collected from the institutional database from March 2011 to January 2021. Clinicopathological data at diagnosis, perioperative and postoperative data, and first recurrence were collected and analyzed. ER was defined via receiver operating characteristic curve. Prognostic factors were evaluated using the Kaplan-Meier method and Cox proportional hazards modeling.

RESULTS

We included 131 patients. The optimal cut off value of recurrence-free survival (RFS) to differentiate between ER (n = 55, 41.9%) and late recurrence (LR) (n = 76, 58.1%) was 8 mo. The median post-recurrence survival (PRS) of ER and LR was 1.4 mo and 2.9 mo, respectively (P = 0.008) but PRS was not strongly associated with RFS (R² = 0.04). Risk factors included age ≥ 70 years [hazard ratio (HR) = 1.752, P = 0.047], preoperative concurrent chemoradiotherapy (HR = 3.683, P < 0.001), colostomy creation (HR = 2.221, P = 0.036), and length of stay > 9 d (HR = 0.441, P = 0.006).

CONCLUSION

RFS of 8 mo was the optimal cut-off value. Although ER was not associated with PRS, it was still related to prognosis; thus, intense surveillance is recommended.

A large population-based and validated study on the follow-up management and supportive strategy of locally advanced rectal cancer patients

OBJECTIVE

Our objective was to evaluate the predictive factors and metastatic time for liver and lung metastasis in locally advanced rectal cancer (RC) patients.

METHODS

Univariate and multivariate analysis were performed to identify risk factors and prognostic factors for liver metastasis and lung metastasis in RC. Survival probabilities were calculated using the Kaplan-Meier model and compared using the log-rank test between groups. The probability of time-to-event occurrence was calculated using the random survival forest model. Finally, the SEER database was used to verify our findings.

RESULTS

Our results indicated that pathological T stage and pathological N stage were independent predictive factors for liver metastasis. Furthermore, CEA level, pathological T stage, and tumor deposit were independent predictive factors for lung metastasis. Based on the results of a multivariate Cox analysis, we categorized patients with liver and lung metastasis into three groups based on their scores. The results revealed that patients with higher scores had a higher probability of experiencing metastasis. For liver metastasis, Groups 1, 2, and 3 all exhibited higher occurrence rates within the first 24 months. However, for lung metastasis, Group 4 showed the highest occurrence rate at the 12th month, while Groups 5 and 6 exhibited the highest occurrence rates at the 15th month.

CONCLUSIONS

In summary, we developed predictive models to determine the likelihood of liver and lung metastasis in RC patients. It is crucial to implement a more intensive surveillance program for patients with unfavorable risk profiles in order to facilitate early detection of metastasis.

Colorectal cancer

Despite decreased incidence rates in average-age onset patients in high-income economies, colorectal cancer is the third most diagnosed cancer in the world, with increasing rates in emerging economies. Furthermore, early onset colorectal cancer (age ≤50 years) is of increasing concern globally. Over the past decade, research advances have increased biological knowledge, treatment options, and overall survival rates. The increase in life expectancy is attributed to an increase in effective systemic therapy, improved treatment selection, and expanded locoregional surgical options. Ongoing developments are focused on the role of sphincter preservation, precision oncology for molecular alterations, use of circulating tumour DNA, analysis of the gut microbiome, as well as the role of locoregional strategies for colorectal cancer liver metastases. This overview is to provide a general multidisciplinary perspective of clinical advances in colorectal cancer.

Incidence of late recurrence and second primary cancers 5-10 years after non-metastatic colorectal cancer

The fraction of patients who are cancer-free survivors 5 years after curative-intended surgery for colorectal cancer (CRC) is increasing, suggesting that extending surveillance beyond 5 years may be indicated. Here we estimate the incidence of late recurrence, metachronous CRC, and second primary cancers 5-10 years postoperative. All patients resected for UICC stage I-III CRC in Denmark through 2004-2013 were identified. Through individual-level linkage of nationwide health registry data, recurrence status was determined using a validated algorithm. Cancer-free survivors 5 years after surgery, were included. Cumulative incidence functions (CIF) of late recurrence, metachronous CRC, and second primary cancer 5-10 years postoperative were constructed. Subdistribution hazards ratios (sHR) were computed using Fine-Gray regression. Among 8883 patients, 370 developed late recurrence (5-10-year CIF = 4.1%, 95%CI: 3.7%-4.6%), 270 metachronous CRC (5-10-year CIF = 3.0%, 95%CI: 2.7%-3.4%), and 635 a second primary cancer (5-10-year CIF = 7.2%, 95%CI: 6.7%-7.7%). The risk of late recurrence was reduced for patients operated in 2009-2013 compared to 2004-2008 (2.9% vs. 5.6%, sHR = 0.52, 95% CI: 0.42-0.65). The risk of metachronous CRC was likewise reduced from 4.1% to 2.1% (sHR = 0.50, 95%CI: 0.39-0.65). While the risk of second primary cancer did not change between 2009-2013 and 2004-2008 (7.1% vs. 7.1%, sHR = 0.98, 95% CI: 0.84-1.15). Using nation-wide 10-year follow-up data, we document that the incidences of late recurrence and metachronous CRC are low and decreasing from 2004 to 2013. Thus, despite increasing numbers of long-term cancer survivors, the data do not advocate for extending CRC-specific surveillance beyond 5 years.

Ureter Metastasis From Colorectal Cancer Revealed on 18 F-FDG PET/CT

ABSTRACT

The involvement of the ureter as a site of metastasis of colorectal cancer is quite rare. Here we present FDG PET/CT findings of the right ureter metastasis from colon cancer in a patient after colectomy 6 years ago. 18 F-FDG PET/CT showed increased 18 F-FDG uptake in the right ureter with SUV max of 4.3. The pathology and immunohistochemistry confirmed the diagnosis of ureter metastasis from colon cancer.

Predicting 5-year recurrence risk in colorectal cancer: development and validation of a histology-based deep learning approach

BACKGROUND

Accurate estimation of the long-term risk of recurrence in patients with non-metastatic colorectal cancer (CRC) is crucial for clinical management. Histology-based deep learning is expected to provide more abundant information for risk stratification.

METHODS

We developed and validated a weakly supervised deep-learning model for predicting 5-year relapse-free survival (RFS) to stratify patients with different risks based on histological images from three hospitals of 614 cases with non-metastatic CRC. A deep prognostic factor (DL-RRS) was established to stratify patients into high and low-risk group. The areas under the curve (AUCs) were calculated to evaluate the performances of models.

RESULTS

Our proposed model achieves the AUCs of 0.833 (95% CI: 0.736-0.905) and 0.715 (95% CI: 0.647-0.776) on validation cohort and external test cohort, respectively. The 5-year RFS rate was 45.7% for high DL-RRS patients, and 82.5% for low DL-RRS patients respectively in the external test cohort (HR: 3.89, 95% CI: 2.51-6.03, P < 0.001). Adjuvant chemotherapy was associated with improved RFS in Stage II patients with high DL-RRS (HR: 0.15, 95% CI: 0.06-0.38, P < 0.001).

CONCLUSIONS

DL-RRS has a good predictive performance of 5-year recurrence risk in CRC, and will better serve the clinical decision-making.

An Unusual and Protracted Course of a Haggitt 3 Malignant Polyp Recurrence

Timely detection of colorectal cancer recurrence is paramount, as treatment of early-stage recurrence greatly improves survival and outcomes. Current guidelines outline post-resection surveillance through endoscopy, CT imaging, and tumor markers for five years; however, there is minimal data to guide follow-up beyond this. We present the case of a 60-year-old female with locoregional recurrence 15 years after endoscopic mucosal resection of a low-grade Haggit level 3 sigmoid colon polyp. Unusually the recurrence was noted as an incidental finding following investigation of an elevated alpha-fetoprotein level post liver transplant, and a retrospective review of imaging revealed a calcified sigmoid mesentery mass. While surgical pathology revealed locoregional recurrence, there was no evidence of this on surveillance and preoperative colonoscopy. Through this case, we discuss the risk factors for late recurrence of colorectal cancer whilst exploring the literature and guidelines around this subset of patients. As new guidelines are developed, it may be important to consider late recurrence and individualize follow-up regimes based on risk factors.

Late Local Recurrence after Neoadjuvant Therapy and Radical Resection for Locally Advanced Rectal Cancer

Neoadjuvant radiochemotherapy (RCT) and lately total neoadjuvant therapy (TNT) improved local recurrence rates of rectal cancer significantly compared to total mesorectal excision (TME) alone. Yet the occurrence and impact of late local recurrences after many years appears to be a distinct biological problem. We included n = 188 patients with rectal cancer after RCT and radical resection in this study; n = 38 of which had recurrent disease (sites: local (8.0%), liver (6.4%), lung (3.7%)). We found that 68% of all recurrences developed within the first two years. Four patients, however, experience recurrence >8 years after surgery. Here, we report and characterize four cases of late local recurrence (10% of patients with recurrent disease), suggesting that neoadjuvant therapy in principle delays local recurrence.

Genetic Polymorphisms and Tumoral Mutational Profiles over Survival in Advanced Colorectal Cancer Patients: An Exploratory Study

Colorectal cancer is a common disease, both in Chile and worldwide. The most widely used chemotherapy schemes are based on 5-fluorouracil (5FU) as the foundational drug (FOLFOX, CapeOX). Genetic polymorphisms have emerged as potential predictive biomarkers of response to chemotherapy, but conclusive evidence is lacking. This study aimed to investigate the role of genetic variants associated with 5FU-based chemotherapy on therapeutic response, considering their interaction with oncogene mutations (KRAS, NRAS, PI3KCA, AKT1, BRAF). In a retrospective cohort of 63 patients diagnosed with metastatic colorectal cancer, a multivariate analysis revealed that liver metastases, DPYD, ABCB1, and MTHFR polymorphisms are independent indicators of poor prognosis, irrespective of oncogene mutations. BRAF wild-type status and high-risk drug-metabolism polymorphisms correlated with a poor prognosis in this Chilean cohort. Additionally, findings from the genomics of drug sensitivity (GDSC) project demonstrated that cell lines with wild-type BRAF have higher IC50 values for 5-FU compared to BRAF-mutated cell lines. In conclusion, the genetic polymorphisms DPYDrs1801265, ABCB1rs1045642, and MTHFRrs180113 may serve as useful biomarkers for predicting a poor prognosis in patients undergoing 5-fluorouracil chemotherapy, regardless of oncogene mutations.

Recurrence Patterns and Risk Factors after Curative Resection for Colorectal Cancer: Insights for Postoperative Surveillance Strategies

This study aimed to assess recurrence patterns and related risk factors following curative resection of colorectal cancer (CRC). This retrospective observational study was conducted at a tertiary care center, including 2622 patients with stage I-III CRC who underwent curative resection between 2008 and 2018. Hazard rates of recurrence were calculated using a hazard function. The primary outcome was the peak recurrence time after curative resection and secondary outcomes were prognostic factors associated with recurrence. Over a median follow-up period of 53 months, the overall, locoregional and systemic recurrence rates were 8.9%, 0.7%, and 8.5%, respectively. Recurrence rates were significantly higher for rectal cancer (14.9% overall, 4.4% locoregionally, and 12.3% systemically) than for colon cancer (all p < 0.001). The peak recurrence time was 11 months, with variations in hazard rates and curves depending on the tumor location, stage, and risk factors. Patients with AL or CRM involvement exhibited a distinct pattern, with a high hazard rate in the early postoperative period. Understanding these recurrence patterns and risk factors is crucial for establishing effective postoperative surveillance strategies. Our findings suggested that short-interval surveillance should be considered during the first 2 years post-surgery, particularly for high-risk patients who should receive early attention.

Survivorship in Early-Stage Rectal Cancer Patients Who Have Received Combined Modality Therapy

Survival rates in early-stage rectal cancer patients have increased over the past few decades. Societies such as the National Comprehensive Cancer Network (NCCN), American Cancer Society (ACS), American Society of Clinical Oncology (ASCO), and European Society of Medical Oncology (ESMO) have proposed guidelines related to cancer survivorship care including formal recommendations to address the needs in early-stage rectal cancer survivors. These guidelines, in addition to new clinical research findings in survivorship will be reviewed, specifically looking at physical, psychosocial, and financial concerns in rectal cancer survivorship.

Colon Cancer Survivorship in Patients Who Have Received Adjuvant Chemotherapy

The number of colon cancer survivors in the United States is increasing due to improved early detection, better treatments that extend survival, and the growing aging population who are at high risk for cancer. Following initial active treatment, colon cancer survivors experience a wide range of long-term physical, psychological, and socio-economic effects that impact their overall well-being. Healthcare providers caring for survivors need to prioritize not only monitoring for cancer recurrence but also optimizing their overall health through addressing these long-term effects; managing their comorbidities; promoting healthy behaviors (like exercise, nutrition, and weight loss); and screening for a second primary cancer depending on their risk. Personalized survivorship care plans should be formulated clearly outlining the roles of various healthcare providers involved in their care. Our review article focuses on these various aspects of colon cancer survivorship, including surveillance for cancer recurrence specific to those who received adjuvant chemotherapy with curative intent.

Two cases of colorectal liver metastasis with residual liver recurrence after a long recurrence-free survival period

BACKGROUND

The rate of residual liver recurrence after the resection of colorectal liver metastases is high, and most cases recur within 5 years of the initial hepatectomy. Here, we report two cases of residual liver recurrence after radical resection of colorectal liver metastases after a long recurrence-free survival period.

CASE PRESENTATION

Case 1 involved a 62-year-old woman treated for ascending colon cancer in April 2011 who underwent right hepatectomy for synchronous colorectal liver metastasis in April 2012. However, in September 2021, computed tomography revealed residual recurrence in the lateral segment of the liver, and a lateral segmentectomy of the liver was performed. In Case 2, a 52-year-old man treated for cecal cancer in July 2002 underwent lateral segmentectomy of the liver for metachronous colorectal liver metastasis in October 2006. Subsequently, there was no recurrence; however, computed tomography showed residual liver recurrence in the right lobe of the liver in October 2021, and an expanded posterior hepatic segmentectomy was performed. Histopathological findings in both cases were consistent with colorectal liver metastases.

CONCLUSIONS

We encountered two cases in which residual liver recurrence was observed after a long period of recurrence-free survival. Although rare, there have been a few cases of late recurrence of liver metastases after radical resection of cancer liver metastases.

Impact of regional lymph node metastasis on pulmonary metastasis as the first recurrence site

Little is known about the impact of regional lymph node metastasis (LNM) on the first recurrence sites following curative colorectal cancer (CRC) surgery. The present study aimed to clarify the relationship between regional LNM stratified by N status and the first recurrence pattern in patients with stage I-III CRC. We performed a retrospective analysis of 1181 consecutive patients with stage I-III CRC who underwent curative surgery between 2010 and 2018. The total sample size included 1181 patients who underwent elective stage I-III CRC surgery. Median follow-up time was 60 months, and median time to recurrence was 12 months. Overall, the numbers of liver recurrence and pulmonary recurrence were 94 (7.9%) and 70 (5.9%), respectively. Higher N status was significantly associated with increased risk of pulmonary recurrence (N0 vs. N1a, p = 0.02; N0 vs. N1b, p < 0.01; N0 vs. N2a, p < 0.01; N0 vs. N2b, p < 0.01) and worse pulmonary recurrence-free survival, but not other recurrences. In Non-LNM patients, on the other hand, advanced T status was associated with increased risk of pulmonary recurrence. The regional LNM was strongly associated with pulmonary metastasis as the first recurrence site following stage I-III CRC resection.

Postoperative recurrence in locally advanced rectal cancer: how does neoadjuvant treatment affect recurrence pattern?

BACKGROUND

The treatment strategy for locally advanced rectal cancer (LARC) has recently expanded from total mesorectal excision to additional neoadjuvant chemoradiotherapy (nCRT) and/or systemic chemotherapy (NAC). Data on disease recurrence after each treatment strategy are limited.

METHODS

Clinical stage II to III rectal cancer patients who underwent curative surgery between July 2005 and February 2021 were analyzed. The cumulative incidence and site of first recurrence were assessed. The median follow-up duration was 4.6 years.

RESULTS

Among the 332 patients, we performed nCRT and NAC in 15.4% (N=51) and 14.8% (N=49), respectively. The overall recurrence rate was 23.5% (N=78). Although several differences in tumor stage or location were observed, there was no significant difference in the rate among the surgery alone (N=54, 23.3%), nCRT (N=11, 21.6%), and NAC (N=13, 26.5%) groups. In this cohort, the local recurrence rate (18.4%) was higher than the rate of distant metastasis in the NAC group (14.3%). All patients with recurrence in the nCRT group had distant metastases (N=11: one patient had distant and local recurrences simultaneously). For pathological stage 0-I, the recurrence rate was higher in the nCRT and NAC groups than in the surgery-alone group (nCRT, 10.0%; NAC, 15.4%; and surgery-alone, 2.0%). Curative-intent resection of distant-only recurrences significantly improved patients' overall survival (hazard ratio [95% confidence interval], 0.34 [0.14-0.84]), which was consistent even when stratified according to neoadjuvant treatment. Regardless of neoadjuvant treatment, >80% of recurrences occurred in the first 2.2 years, and 98.7% within 5 years after surgery.

CONCLUSION

Regardless of neoadjuvant treatment, detecting distant metastases with intensive surveillance, particularly in the first 2 years after surgery, is important. Also, even if neoadjuvant treatment can downstage LARC to pathological stage 0-I, careful follow-up is needed.

Local Recurrences in Rectal Cancer: MRI vs. CT

Rectal cancers are often considered a distinct disease from colon cancers as their survival and management are different. Particularly, the risk for local recurrence (LR) is greater than in colon cancer. There are many factors predisposing to LR such as postoperative histopathological features or the mesorectal plane of surgical resection. In addition, the pattern of LR in rectal cancer has a prognostic significance and an important role in the choice of operative approach and. Therefore, an optimal follow up based on imaging is critical in rectal cancer. The aim of this review is to analyse the risk and the pattern of local recurrences in rectal cancer and to provide an overview of the role of imaging in early detection of LRs. We performed a literature review of studies published on Web of Science and MEDLINE up to January 2023. We also reviewed the current guidelines of National Comprehensive Cancer Network (NCCN) and the European Society for Medical Oncology (ESMO). Although the timing and the modality of follow-up is not yet established, the guidelines usually recommend a time frame of 5 years post surgical resection of the rectum. Computed Tomography (CT) scans and/or Magnetic Resonance Imaging (MRI) are the main imaging techniques recommended in the follow-up of these patients. PET-CT is not recommended by guidelines during post-operative surveillance and it is generally used for problem solving.

Stage IV Colorectal Cancer Management and Treatment

(1) Background: Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer-related mortality worldwide. Up to 50% of patients with CRC develop metastatic CRC (mCRC). Surgical and systemic therapy advances can now offer significant survival advantages. Understanding the evolving treatment options is essential for decreasing mCRC mortality. We aim to summarize current evidence and guidelines regarding the management of mCRC to provide utility when making a treatment plan for the heterogenous spectrum of mCRC. (2) Methods: A comprehensive literature search of PubMed and current guidelines written by major cancer and surgical societies were reviewed. The references of the included studies were screened to identify additional studies that were incorporated as appropriate. (3) Results: The standard of care for mCRC primarily consists of surgical resection and systemic therapy. Complete resection of liver, lung, and peritoneal metastases is associated with better disease control and survival. Systemic therapy now includes chemotherapy, targeted therapy, and immunotherapy options that can be tailored by molecular profiling. Differences between colon and rectal metastasis management exist between major guidelines. (4) Conclusions: With the advances in surgical and systemic therapy, as well as a better understanding of tumor biology and the importance of molecular profiling, more patients can anticipate prolonged survival. We provide a summary of available evidence for the management of mCRC, highlighting the similarities and presenting the difference in available literature. Ultimately, a multidisciplinary evaluation of patients with mCRC is crucial to selecting the appropriate pathway.

Is a less-intensive follow-up for colon cancer in early stages reasonable?

PURPOSE

Patients with colon cancer are usually included in an intensive 5-year surveillance protocol after curative resection, independent of the tumor stage, though early stages have a considerably lower risk of recurrence. The aim of this study was to analyze the adherence to an intensive follow-up and the risk of recurrence in patients with colon cancer in UICC stages I and II.

METHODS

In this retrospective study, we assessed patients who underwent resection for colon cancer in UICC stages I and II between 2007 and 2016. Data were collected on demographics, tumor stages, therapy, surveillance, recurrent disease, and oncological outcome.

RESULTS

Of the 232 included patients, 43.5% (n = 101) reached the 5-year follow-up disease-free. Seven (7.5%) patients in stage UICC I and sixteen (11.5%) in UICC II had a recurrence, with the highest risk in patients with pT4 (26.3%). A metachronous colon cancer was detected in four patients (1.7%). The therapy of recurrence was intended to be curative in 57.1% (n = 4) of UICC stage I and in 43.8% (n = 7) of UICC stage II, but only in one of seven patients over 80 years. 44.8% (n = 104) of the patients were lost to follow-up.

CONCLUSION

A postoperative surveillance in patients with colon cancer is important and recommended as a recurrent disease can be treated successfully in many patients. However, we suggest that a less intensive surveillance protocol is reasonable for patients with colon cancer in early tumor stages, especially in UICC stage I, as the risk of recurrent disease is low. With elderly and/or frail patients in a reduced general condition, who will not endure further specific therapy in case of a recurrence, the performance of the surveillance should be discussed: we recommend a significant reduction or even renunciation.

Surveillance strategies following curative resection and non-operative approach of rectal cancer: How and how long? Review of current recommendations

Different follow-up strategies are available for patients with rectal cancer following curative treatment. A combination of biochemical testing and imaging investigation, associated with physical examination are commonly used. However, there is currently no consensus about the types of tests to perform, the timing of the testing, and even the need for follow-up at all has been questioned. The aim of this study was to review the evidence of the impact of different follow-up tests and programs in patients with non-metastatic disease after definitive treatment of the primary. A literature review was performed of studies published on MEDLINE, EMBASE, the Cochrane Library and Web of Science up to November 2022. Current published guidelines from the most authoritative specialty societies were also reviewed. According to the follow-up strategies available, the office visit is not efficient but represents the only way to maintain direct contact with the patient and is recommended by all authoritative specialty societies. In colorectal cancer surveillance, carcinoembryonic antigen represents the only established tumor marker. Abdominal and chest computed tomography scan is recommended considering that the liver and lungs are the most common sites of recurrence. Since local relapse in rectal cancer is higher than in colon cancer, endoscopic surveillance is mandatory. Different follow-up regimens have been published but randomized comparisons and meta-analyses do not allow to determine whether intensive or less intensive follow-up had any significant influence on survival and recurrence detection rate. The available data do not allow the drawing of final conclusions on the ideal surveillance methods and the frequency with which they should be applied. It is very useful and urgent for clinicians to identify a cost-effective strategy that allows early identification of recurrence with a special focus for high-risk patients and patients undergoing a “watch and wait” approach.

A Comparison between Open and Minimally Invasive Techniques for the Resection of Colorectal Liver Metastasis

The liver is the most common site of colorectal cancer metastasis. Liver surgery is a cornerstone in treatment, with progressive expansion of minimally invasive surgery (MIS). This study aims to compare short- and long-term outcomes of open surgery and MIS for the treatment of colorectal adenocarcinoma liver metastasis during the first three years of increasing caseload and implementation of MIS use in liver surgery. All patients treated between November 2018 and August 2021 at Careggi Teaching Hospital in Florence, Italy, were prospectively entered into a database and retrospectively reviewed. Fifty-one patients were resected (41 open, 10 MIS). Considering that patients with a significantly higher number of lesions underwent open surgery and operative results were similar, postoperative morbidity rate and length of hospital stay were significantly higher in the open group. No differences were found in the pathological specimen. The postoperative mortality rate was 2%. Mean overall survival and disease-free survival were 46 months (95% CI 42-50) and 22 months (95% CI 15.6-29), respectively. The use of minimally invasive techniques in liver surgery is safe and feasible if surgeons have adequate expertise. MIS and parenchymal sparing resections should be preferred whenever technically feasible.

Machine learning based prognostic model of Chinese medicine affecting the recurrence and metastasis of I-III stage colorectal cancer: A retrospective study in China

Background

To construct prognostic model of colorectal cancer (CRC) recurrence and metastasis (R&M) with traditional Chinese medicine (TCM) factors based on different machine learning (ML) methods. Aiming to offset the defects in the existing model lacking TCM factors.

Methods

Patients with stage I-III CRC after radical resection were included as the model data set. The training set and the internal verification set were randomly divided at a ratio of 7: 3 by the "set aside method". The average performance index and 95% confidence interval of the model were calculated by repeating 100 tests. Eight factors were used as predictors of Western medicine. Two types of models were constructed by taking "whether to accept TCM intervention" and "different TCM syndrome types" as TCM predictors. The model was constructed by four ML methods: logistic regression, random forest, Extreme Gradient Boosting (XGBoost) and support vector machine (SVM). The predicted target was whether R&M would occur within 3 years and 5 years after radical surgery. The area under curve (AUC) value and decision curve analysis (DCA) curve were used to evaluate accuracy and utility of the model.

Results

The model data set consisted of 558 patients, of which 317 received TCM intervention after radical resection. The model based on the four ML methods with the TCM factor of "whether to accept TCM intervention" showed good ability in predicting R&M within 3 years and 5 years (AUC value > 0.75), and XGBoost was the best method. The DCA indicated that when the R&M probability in patients was at a certain threshold, the models provided additional clinical benefits. When predicting the R&M probability within 3 years and 5 years in the model with TCM factors of "different TCM syndrome types", the four methods all showed certain predictive ability (AUC value > 0.70). With the exception of the model constructed by SVM, the other methods provided additional clinical benefits within a certain probability threshold.

Conclusion

The prognostic model based on ML methods shows good accuracy and clinical utility. It can quantify the influence degree of TCM factors on R&M, and provide certain values for clinical decision-making.

Continuous sensing of IFNα by hepatic endothelial cells shapes a vascular antimetastatic barrier

Hepatic metastases are a poor prognostic factor of colorectal carcinoma (CRC) and new strategies to reduce the risk of liver CRC colonization are highly needed. Herein, we used mouse models of hepatic metastatization to demonstrate that the continuous infusion of therapeutic doses of interferon-alpha (IFNα) controls CRC invasion by acting on hepatic endothelial cells (HECs). Mechanistically, IFNα promoted the development of a vascular antimetastatic niche characterized by liver sinusoidal endothelial cells (LSECs) defenestration extracellular matrix and glycocalyx deposition, thus strengthening the liver vascular barrier impairing CRC trans-sinusoidal migration, without requiring a direct action on tumor cells, hepatic stellate cells, hepatocytes, or liver dendritic cells (DCs), Kupffer cells (KCs) and liver capsular macrophages (LCMs). Moreover, IFNα endowed LSECs with efficient cross-priming potential that, along with the early intravascular tumor burden reduction, supported the generation of antitumor CD8+ T cells and ultimately led to the establishment of a protective long-term memory T cell response. These findings provide a rationale for the use of continuous IFNα therapy in perioperative settings to reduce CRC metastatic spreading to the liver.

The Establishment and Experimental Verification of an lncRNA-Derived CD8+ T Cell Infiltration ceRNA Network in Colorectal Cancer

BACKGROUND

Long noncoding RNAs (LncRNA) lead a vital role in colorectal cancer (CRC) development. The infiltrating CD8+ T cell is the main target of immunotherapy. Our study aimed to figure out the potential mechanism of lncRNAs regulating the function of CD8+ T cells in CRC.

METHODS

We collected bulk RNA-seq, miRNA-seq, and single-cell RNA-seq (scRNA-seq) data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. The cibersort algorithm and correlation analysis were used to estimate the abundance of CD8+ T cells and screened out the most relevant lncRNAs. We used scRNA-seq data to identify the main cell lncRNA expressed. Furthermore, one competing endogenous RNA (ceRNA) network focusing on the potential mechanism of lncRNA-derived CD8+ T cell infiltration was constructed. We established a co-culture system to assess the immunosuppressive function of the lncRNA. And we evaluated the effects of the lncRNA on CD8+ T cell cytotoxicity by flow cytometry, qPCR, and clone formation assay.

RESULTS

Three CD8+ T cell infiltration-related lncRNAs were identified, and LINC00657 was expressed mainly in tumor cells, negatively associated with CD8+ T cell infiltration. Hsa-miRNA-1224-3p and hsa-miRNA-338-5p and SCD, ETS2, UBE2H, and YY1 were identified to construct the ceRNA network. Immunosuppression-related tumor marker CD155 was proved to be positively correlated with LINC00657 and mRNAs in the ceRNA network. In addition, we proved that LINC00657 could impair the cytotoxicity of CD8+ T cells, and its expression was positively associated with CD155 in vitro.

CONCLUSIONS

We successfully constructed an lncRNA-derived CD8+ T cell infiltration ceRNA network in CRC. LINC00657 may play a leading role in the CRC immune escape and could be a novel immunotherapy target.

IgG-like Bispecific Antibody CD3×EpCAM Generated by Split Intein Against Colorectal Cancer

Background: Colorectal cancer is a commonly diagnosed cancer with high mortality worldwide. Postoperative recidivation and metastasis still are the main challenges in clinical treatments. Thus, it is urgent to develop new therapies against colorectal cancer. Epithelial Cell Adhesion Molecule (EpCAM) is overexpressed in colorectal cancer cells and strongly associated with cancer development. Bispecific antibody (BsAb) is a kind of promising immunotherapy, which could recognize T cells and cancer cells simultaneously to achieve the anti-tumor effects. Methods: A bispecific antibody targeting EpCAM and CD3 with IgG format was genereated by split intein based on the Bispecific Antibody by Protein Splicing" platform. In vitro, the affinity of CD3×EpCAM BsAb was determined by Biolayer interferometry, its cytotoxicity was detected by LDH release assay, T cell recruitment and activation was detected by Flow Cytometry. In vivo, its pharmacokinetic parameters were detected, and anti-tumor effects were evaluated on the tumor cell xenograft mouse model. Results: The results showed that the CD3×EpCAM BsAb could activate and recruit T cells via binding colorectal cells and T cells, which could lead to more potent cytotoxicity to various colorectal cell lines than its parent EpCAM monoclonal antibody (mAb) in vitro. The CD3×EpCAM BsAb had similar pharmacokinetic parameters with EpCAM mAb and inhibits tumor growth on the SW480 tumor cell xenograft mouse model. Conclusion: The CD3×EpCAM BsAb could be a promising candidate for colorectal cancer treatment.

Survival Advantage Following TAG-72 Antigen-Directed Cancer Surgery in Patients With Colorectal Carcinoma: Proposed Mechanisms of Action

Patients with colorectal carcinoma (CRC) continue to have variable clinical outcomes despite undergoing the same surgical procedure with curative intent and having the same pathologic and clinical stage. This problem suggests the need for better techniques to assess the extent of disease during surgery. We began to address this problem 35 years ago by injecting patients with either primary or recurrent CRC with 125I-labeled murine monoclonal antibodies against the tumor-associated glycoprotein-72 (TAG-72) and using a handheld gamma-detecting probe (HGDP) for intraoperative detection and removal of radioactive, i.e., TAG-72-positive, tissue. Data from these studies demonstrated a significant difference in overall survival data (p < 0.005 or better) when no TAG-72-positive tissue remained compared to when TAG-72-positive tissue remained at the completion of surgery. Recent publications indicate that aberrant glycosylation of mucins and their critical role in suppressing tumor-associated immune response help to explain the cellular mechanisms underlying our results. We propose that monoclonal antibodies to TAG-72 recognize and bind to antigenic epitopes on mucins that suppress the tumor-associated immune response in both the tumor and tumor-draining lymph nodes. Complete surgical removal of all TAG-72-positive tissue serves to reverse the escape phase of immunoediting, allowing a resetting of this response that leads to improved overall survival of the patients with either primary or recurrent CRC. Thus, the status of TAG-72 positivity after resection has a significant impact on patient survival.

Isolated liver metastasis detected 11 years after the curative resection of rectal cancer: A case report

BACKGROUND

The duration of surveillance after curative resection of colorectal cancer (CRC) is generally 5 years. The overall incidence of recurrence more than 5 years after surgery for CRC in Japan has been reported to be 0.6%. Moreover, it is rare for CRC to have metachronous liver metastasis more than 10 years after surgery. Here, we present a case of liver metastasis detected 11 years after the curative resection of rectal cancer.

CASE SUMMARY

A 72-year-old man was referred to our hospital after a liver tumor was detected by abdominal ultrasonography at another hospital. He had undergone surgery for rectal cancer 11 years previously. Contrast-enhanced computed tomography (CT) showed a tumor with a diameter of approximately 8 cm in the posterior segment, which was weakly and gradually enhanced. ¹⁸F-fluorodeoxyglucose-positron emission tomography/CT showed an abnormally high uptake on the tumorous lesion, which showed that the tumor appeared to spread convexly along the intrahepatic bile ducts. Intrahepatic cholangiocarcinoma was therefore diagnosed, and he had an extended right posterior sectionectomy and regional lymph node dissection. Histopathological examination showed that the tumor was a moderately differentiated adenocarcinoma and showed the same pathological characteristics as the rectal cancer. Immunohistological examination showed that the cancer cells of both the liver tumor and rectal cancer were positive for cytokeratin (CK) 20 and weakly positive for CK 7. These findings were consistent with the liver metastasis from the rectal cancer.

CONCLUSION

It is possible that a liver tumor is metastatic in a patient with a previous history of CRC, even if it was more than 10 years earlier.

Clinicopathological Features of Stage I-III Colorectal Cancer Recurrence Over 5 Years After Radical Surgery Without Receiving Neoadjuvant Therapy: Evidence From a Large Sample Study

Late recurrence (5 or more years) after radical resection of colorectal cancer (CRC) is rare. This study aims to investigate the features of late recurrence in stage I-III CRC. A total of 9,754 stage I-III patients with CRC who underwent radical surgery without receiving neoadjuvant therapy, at the Fudan University Shanghai Cancer Center (FUSCC), were enrolled in this study. These patients were divided into three groups: early recurrence (3 months-2 years), intermediate recurrence (2-5 years), and late recurrence (over 5 years). The median duration of follow-up was 53.5 ± 30.1 months. A total of 2,341 (24.0%) patients developed recurrence. The late recurrence rate was 11.7%. Patients with a higher risk of late recurrence were more likely to be older, to be at the T4 stage, to have a higher degree of colon cancer, to have a lower frequency of signet ring cell carcinoma, to have fewer poorly differentiated tumors, to be at the early stage of CRC, along with less perineural and vascular invasions. Multivariate logistic regression analysis identified age, differentiation, T stage, N stage, perineural, and vascular invasions as independent factors for late recurrence. Late recurrent CRC has some distinctive characteristics. Although recurrence over 5 years after surgery is infrequent, an enhanced follow-up is still needed for the selected patients after 5 years.

Late Recurrence in a Rectal Cancer Patient Who Underwent Preoperative Chemoradiotherapy Followed by Local Excision: A Case Report

Some patients who have undergone preoperative chemoradiotherapy (CRT) following surgery have been diagnosed with late recurrence more than 5 years after treatment, raising questions about the possible benefit extending surveillance beyond the recommended 5 years. In 2011, a 71-year-old male patient was diagnosed with T3N+ low-lying rectal cancer located 3 cm from the anal verge before undergoing long-course preoperative CRT. After CRT, the patient was reexamined and diagnosed with ycT1–2N0 lesion, so local excision (LE) was performed. The patient underwent intensive surveillance for up to 5 years, and no evidence of recurrence was found. At 74 months after surgery, the patient was hospitalized for a hematochezia, and local recurrence at the excision site and peritoneal seeding nodules were identified. Considering the late recurrence in this patient, it might be necessary to long-term follow-up beyond 5 years in patients with preoperative CRT followed by LE.

Clinical characteristics and survival of colorectal cancer patients in Korea stratified by age

BACKGROUND/AIMS

This nationwide study was undertaken to determine differences in clinicopathologic characteristics and survival of patients with colorectal cancer (CRC) according to age using big data from the Korean National Health Insurance Service (NHIS).

METHODS

The NHIS data including quality assessment of CRC by the Health Insurance Review & Assessment Service in Korea between 2011 and 2014 were analyzed. Based on age, patients were divided into three groups: not-old patients (< 65), young-old patients (65 to 74 years old) and old-old patients (≥ 75 years old).

RESULTS

We included 71,513 CRC patients. The median follow-up duration was 3.2 years (range, 0.003 to 5.5). Male patients constituted 60%. The median age of patients was 65 years (range, 18 to 102). Colon was the cancer site in 59.8% of not-old patients, 62.9% of young-old patients, and 66.1% of old-old patients. Compared to not-old patients, young-old and old-old patients were more likely to be diagnosed with colon adenocarcinoma and well/moderate differentiation or adequate differentiation (all p < 0.001). Old patients underwent more emergency operation (p < 0.001) and received less adjuvant therapy in stage I-III (p < 0.001). The probability of 3-year survival of young-old or old-old patients was worse than that for not-old patients (hazard ratio [HR], 1.55; 95% confidence interval [CI], 1.46 to 1.64) (HR, 3.19; 95% CI, 3.03 to 3.37).

CONCLUSION

Old patients with CRC show different histology from younger patients. They are more frequently to have colon as primary lesion. They undergo less adjuvant therapy. Further studies and evidence-based guidelines for older patients with CRC are warranted to improve their outcome.

Lymph node metastasis is strongly associated with lung metastasis as the first recurrence site in colorectal cancer

BACKGROUND

The lymphatic system is known to be the primary pathway of metastasis for colorectal cancer. However, beyond regional lymph node metastases, little is known about the pathway of lymphatic metastases and the differences in the recurrence site risk. The aim of this study was to clarify the relationship between lymph node metastasis and the first recurrence site in colorectal cancer.

METHODS

Patients with colorectal cancer who underwent curative resection in our institution between January 2003 and December 2016 were included in this analysis. The relationship between the first recurrence site and clinicopathological factors was analyzed by the Cox regression model and competing risk regression model.

RESULTS

In total, 1,249 patients with colorectal cancer were included in this analysis. We found that the stages of lymph node metastases (N0 vs N1: P = .008, N0 vs N2a: P < .001, N0 vs N2b: P < .001) were significantly associated with lung metastasis in the multivariate analysis. Furthermore, in the competing risk analysis, the stages of lymph node metastases were significantly correlated with lung metastasis (N0 vs N1: P = .002, N0 vs N2a: P < .001, N0 vs N2b: P < .001) but were not correlated with other recurrence sites.

CONCLUSION

The severity of lymph node involvement had a strong correlation with lung metastases in patients with colorectal cancer.

Evaluation of prognostic factors and clinicopathological patterns of recurrence after curative surgery for colorectal cancer

BACKGROUND

Colorectal cancer is a common tumor with a quite high-related mortality. Despite the used curative treatments, patients will develop cancer recurrence in up to 50% of the cases and/or other primary neoplasms. Although most of the recurrences are discovered within 3 years from the first treatment, a small percentage is found after 5 years. The early detection of recurrence is crucial to allow further therapies improving patients' survival. Several follow-up programs have been developed but the optimal one is far from being established.

AIM

To evaluation of potential prognostic factors for timing and patterns of recurrence in order to plan tailored follow-up programs.

METHODS

Perioperative and long-term data of all consecutive patients surgically treated with curative intent, from January 2006 to June 2009, for colorectal adenocar-cinoma, were retrospectively reviewed to find potential prognostic factors associated with: (1) Recurrence incidence; (2) Incidence of an early (within 3 years from surgery) or late recurrence; and (3) Different sites of recurrence. In addition, the incidence of other primary neoplasms has been evaluated in a cohort of patients with a minimum potential follow-up of 10 years.

RESULTS

Our study included 234 patients. The median follow-up period has been 119 ± 46.2 mo. The recurrence rate has been 25.6%. Patients with a higher chance to develop recurrence had also the following characteristics: Higher levels of preoperative glycemia and carcinoembryonic antigen, highest anaesthesiologists Score score, occlusion, received a complex operation performed with an open technique, after a longer hospital stay, and showed advanced tumors. The independent prognostic factors for recurrence were the hospital stay, N stage 2, and M stage 1 (multivariate analysis). Younger ages were significantly associated with an early recurrence onset. Patients that received intermediate colectomies or segmental resections, having an N stage 2 or American Joint Committee on Cancer stage 3 tumors were also associated with a higher risk of liver recurrence, while metastatic diseases at diagnosis were linked with local recurrence. Neoadjuvant treatments showed lung recurrence. Finally, bigger tumors and higher lymph node ratio were associated with peritoneal recurrence (marginally significant). Thirty patients developed a second malignancy during the follow-up time.

CONCLUSION

Several prognostic factors should be considered for tailored follow-up programs, eventually, beyond 5 years from the first treatment.

Tumor microenvironment derived signature predicting relapse-free survival in I-III cancer and preliminary experiment verification

The recurrence in colon cancer contributed to great difficulties in diagnostic and therapeutic treatment. Tumor microenvironment (TME) gains increasing attention recently. After univariate Cox analysis on relapse-free survival (RFS) and ESTIMATE analysis, WGCNA was further conducted to determine the TME and relapse-related genes in I-III colon cancer. Functional enrichment analyses were conducted. Furthermore, seven genes were screened to build a prognostic signature via LASSO and multivariate Cox analysis. Univariate followed multivariate Cox analysis all showed that the risk group calculated by the signature as a significant predictors. The ROC curves showed great prognostic in the internal training group, internal verification group, and independent external verification group. In the training group, the AUC at 1, 3, and 5 years was 0.737, 0.79, and 0.756. In addition, correlation analysis presented that the signature and genes involved in were significantly associated with the TME. Moreover, 3 of 7 genes (FAM78A, SGIP1, and MMP9) were validated to be associated with PDL1 through qRT-PCR.

Is It Time to Introduce PET/CT in Rectal Cancer Guidelines?

At the moment, international guidelines for rectal cancer suggest to consider F-FDG PET/CT scan in a few conditions: (1) at disease presentation in case of suspected or proven metastatic synchronous adenocarcinoma with potentially curable M1 disease; (2) in the recurrence workup for serial carcinoembryonic antigen level elevation; (3) in the recurrence workup with metachronous metastases documented by CT, MRI, or biopsy; (4) in case of strong contraindication to IV contrast agent administration; and (5) to evaluate an equivocal finding on a contrast-enhanced CT or MRI. PET/CT is not indicated in the follow-up or surveillance of rectal cancer. On the other hand, an attentive evaluation of the literature shows that PET/CT may also be used in some circumstances with significant levels of diagnostic accuracy. This review article aims to emphasize differences between current international guidelines and scientific literature in the role of PET/CT in rectal cancer.

Is It Time to Introduce PET/CT in Colon Cancer Guidelines?

International colon cancer guidelines suggest F-FDG PET/CT in a few circumstances: (1) at disease presentation in case of suspected or proven metastatic synchronous adenocarcinoma; (2) in the workup of recurrent colon cancer with metachronous metastases documented by CT, MRI, or biopsy and in case of serial CEA elevation with negative colonoscopy and negative CT; and (3) in case of contraindication to iodine- and gadolinium-based contrast agents. However, review of the literature has shown that PET/CT can also be used in other scenarios with significant levels of diagnostic advantage. This review aims to emphasize differences between guidelines and scientific literature for the use of PET/CT in colon cancer.

Factors associated with colon cancer early, intermediate and late recurrence after surgery for stage I-III: A 5-year prospective study

OBJECTIVE

To identify factors associated with early, intermediate or late recurrence colon cancer recurrence.

METHODS

A total of 1,732 consecutive patients with colon cancer were recruited and followed for a period of 5 years. Recurrence at 1 year (early), from 1 to 2 (early), from 2 to 3 (intermediate) and from 3 to 5 years (late) was the main outcome measures.

RESULTS

Predictors of early recurrence (AUC (95% CI):0.74 (0.70-0.78) were as follows: TNM stage II and III, more than one type of invasion, haemoglobin <10 g/dl, residual tumour (R1), ASA IV, log odds of positive lymph nodes ratio ≥-0.53, perforation, neoadjuvant chemotherapy, infectious complications within 1 year and CEA pre- and post-intervention. These factors remained significant for predicting intermediate (AUC [95% CI]: 0.72 [0.67-0.77]) and late (AUC [95% CI]: 0.68 [0.63-0.74]) recurrence, except for ASA class, log lymph node ratio, perforation and neoadjuvant chemotherapy. Additionally, laterality (left) and medical complications up to 2 years were significant.

CONCLUSIONS

These risk factors show good predictive ability of early, intermediate and late recurrence, confirming factors established by guidelines and adding some others. They could serve to provide more appropriate and accurate treatment and follow-up tailored to patient characteristics.

Less intensive surveillance after radical surgery for stage I-III colorectal cancer by focusing on the doubling time of recurrence

PURPOSE

To propose a new and improved surveillance schedule for colorectal cancer (CRC) patients by focusing on the recurrence rate, resectability, and especially, the tumor doubling time (DT) of recurrent tumors.

METHODS

The subjects of this retrospective review were 1774 consecutive patients who underwent radical surgery for stage I-III CRC between January, 2004 and December, 2015. We calculated the DT by measuring the tumor diameter using computed tomography (CT).

RESULTS

The median DT for recurrences in the liver, lung, peritoneum, and other locations were 35, 72, 85, and 36 days, respectively, (p < 0.001) and tumor growth rates differed according to the organs where recurrence developed. Multiple linear regression analysis showed that the DT was strongly associated with the relapse-free interval from primary surgery (p < 0.001), and that the DT in patients with recurrence detected ≥ 3 years after primary surgery was longer by 151.1 days than that in patients with recurrence detected within 1 year after primary surgery. We proposed a less intensive surveillance, which achieved an average cost reduction of 32.5% compared with conventional surveillance in Japan.

CONCLUSION

We propose a new and more cost-efficient surveillance schedule for CRC surgery patients in the clinical setting.

Analysis of relapse-associated alternative mRNA splicing and construction of a prognostic signature predicting relapse in I-III colon cancer

The literature comprehensively analyzed alternative splicing (AS) events in colon cancer is little and corresponding prognostic signature is still a lack. Based on data of TCGA, the relapse-associated ASs were comprehensively analyzed and a signature was further constructed to predict the relapse in I-III colon cancer. In total 1912 ASs of 1384 mRNA were identified as relapse-associated ASs, protein-protein interactions (PPI) and ASs-splicing factors (SF) interactions network were identified. We finally built a robust signature to predict the relapse of I-III colon cancer with a considerable AUC value in both the training group and the test group. The AUC in the entire set at 1, 3 and 5 year was 0.85, 0.83 and 0.836. Our study provided a profile of relapse-associated ASs in I-III colon cancer and built a robust signature to predict the relapse of I-III colon cancer.

A signature predicting relapse based on integrated analysis on relapse-associated alternative mRNA splicing in I-III rectal cancer

Researches focusing on the effects of alternative splicing (AS) on relapse of rectal cancer is little and signature based on the AS is blank. In this study, bioinformatic analysis was performed to identify and analyze the relapse-associated ASs, a signature was also constructed. In conclusion, 829 relapse-associated ASs of 676 mRNA were identified. 603 proteins with 2119 interactions were involved in the PPI (protein-protein interactions) network. 43 relapse-associated ASs and 64 SFs (splicing factors) with 160 interactions were indicated. Finally, we built a robust signature to predict the relapse of I-III rectal cancer with a high AUC (0.98) of ROC at 1 year. Based on the ASs involved in the signature, 4 molecular subgroups that could distinguish the relapse rate in diverse groups were identified. Our research provided an overview of relapse-associated ASs in I-III rectal cancer.

Prognostic Value of LncRNA HOTAIR in Colorectal Cancer: A Meta-analysis

HOX transcript antisense intergenic RNA (HOTAIR) is one of the most studied long noncoding RNAs (lncRNAs) and is aberrantly expressed in colorectal cancer (CRC). We thus performed a comprehensive study based on meta-analysis and validation of the TCGA database to investigate clinicopathological and prognostic value of HOTAIR in CRC. Six studies enrolling 629 CRC patients were included in the analysis. The results indicated that high HOTAIR expression predicted worse OS (hazard ratio [HR] = 2.46, 95% confidence interval [CI]: 1.82-3.32, P < 0.01) and RFS (HR = 1.97, 95% CI: 1.27-3.05, P < 0.01) for CRC patients. High HOTAIR expression was also significantly associated with venous invasion (OR = 2.53, 95% CI: 1.12-5.68, P = 0.02), advanced tumor infiltration (OR = 3.35, 95% CI: 1.34-8.42, P = 0.01) and distant metastasis (OR = 5.52, 95% CI: 1.22-25.01, P = 0.03). Then, the results were validated by the TCGA database, showing that the up-regulated expression of HOTAIR was significantly related to poor OS (P = 0.01) and RFS (P = 0.04) in CRC. Our meta-analysis indicated that high HOTAIR expression was closely associated with poor clinical outcomes and could be a reliable prognostic biomarker for CRC patients.

A stroma-related lncRNA panel for predicting recurrence and adjuvant chemotherapy benefit in patients with early-stage colon cancer

The heterogeneity in prognoses and chemotherapeutic responses of colon cancer patients with similar clinical features emphasized the necessity for new biomarkers that help to improve the survival prediction and tailor therapies more rationally and precisely. In the present study, we established a stroma‐related lncRNA signature (SLS) based on 52 lncRNAs to comprehensively predict clinical outcome. The SLS model could not only distinguish patients with different recurrence and mortality risks through univariate analysis, but also served as an independent factor for relapse‐free and overall survival. Compared with the conventionally used TNM stage system, the SLS model clearly possessed higher predictive accuracy. Moreover, the SLS model also effectively screened chemotherapy‐responsive patients, as only patients in the low‐SLS group could benefit from adjuvant chemotherapy. The following cell infiltration and competing endogenous RNA (ceRNA) network functional analyses further confirmed the association between the SLS model and stromal activation‐related biological processes. Additionally, this study also identified three phenotypically distinct colon cancer subtypes that varied in clinical outcome and chemotherapy benefits. In conclusion, our SLS model may be a significant determinant of survival and chemotherapeutic decision‐making in colon cancer and may have a strong clinical transformation value.

FDG PET/CT in colorectal cancer

Colorectal cancer is the third most frequent cancer worldwide. Although its incidence is increasing, mainly in those aged under50, mortality has decreased by 50% in the more developed countries, principally due to the adoption of new practices in prevention, diagnosis and treatment. In particular, the various diagnostic imaging modalities allow improved therapeutic decision-making, evaluation of the response and early detection of recurrence. The aim of this paper is to review the available scientific evidence on the value of positron emission tomography with ¹⁸F-FDG (¹⁸F-FDG PET/CT) in the colorectal cancer, with special emphasis on the indications of the guidelines and recommendations of the main international scientific associations regarding this imaging technique.

Evaluating the recent developments in palliative chemotherapy for metastatic colorectal cancer

The incidence of colorectal cancer (CRC) has increased. CRC is the third most common cancer and the fourth most common cause of cancer-related deaths in Korea. Palliative chemotherapy can be used to shrink tumors and ease symptoms caused by the cancer when cure is not possible. It is important to identify chemotherapeutic agents that can be used to effectively treat metastatic CRC (mCRC) and thus improve the survival and quality of life of patients with mCRC. This review aimed to evaluate the recent developments in palliative chemotherapy for mCRC and the biological or targeted agents used based on genetic alterations.