Colonoscopy Surveillance after Colorectal Cancer Resection: Recommendations of the US Multi-Society Task Force on Colorectal Cancer

Allosteric SHP2 inhibition enhances regorafenib's effectiveness in colorectal cancer treatment

Colorectal cancer (CRC) is the third most common cancer globally. Regorafenib, a multi-target kinase inhibitor, has been approved for treating metastatic colorectal cancer patients who have undergone at least two prior standard anti-cancer therapies. However, regorafenib efficacy as a single agent remains suboptimal. A promising target at the crossroads of multiple signaling pathways is the Src homology 2 domain-containing protein tyrosine phosphatase (SHP2). However, a combination approach using SHP2 inhibitors (SHP099) and anti-angiogenic drugs (Regorafenib) has not been reported in current research. In this study, we conducted in vitro experiments combining SHP099 and regorafenib and established an MC-38 colon cancer allograft mouse model. Our results revealed that co-treatment with SHP099 and regorafenib significantly inhibited cell viability and altered the biological characteristics of tumor cells compared with treatment alone in vitro. Furthermore, the combination strategy demonstrated superior therapeutic efficacy compared to monotherapy with either drug. This was evidenced by reduced tumor size, decreased proliferation, increased apoptosis, normalized tumor microvasculature, and improved antitumor immune response in vivo. These findings suggest that the combination of an SHP2 inhibitor and regorafenib is a promising therapeutic approach for patients with colorectal cancer.

Early Surveillance Endoscopy Should Be Performed Selectively After Transanal Endoscopic Microsurgery for Rectal Lesions

Introduction Local recurrence (LR) rates after transanal endoscopic microsurgery (TEM) are unclear, and the utility of early postoperative surveillance for low-risk lesions is unknown. This study aimed to define LR after TEM for benign polyps and invasive adenocarcinoma, describe risk factors for LR, and evaluate the utility of early surveillance endoscopy. Methods This retrospective cohort study was conducted at two hospitals in Winnipeg, Manitoba, Canada. Adult patients who underwent TEM between 2009 and 2020 were evaluated for inclusion. The primary outcome was the rate of LR on surveillance endoscopy. Other outcomes included risk factors for LR and diagnostic yield of surveillance endoscopy. Results Among 357 patients who underwent TEM for benign polyps, LR was 10.5% (95% confidence interval (CI) 5.8-15.2) at three years. Positive margin was correlated with LR on multivariate analysis (hazard ratio (HR) 8.01, 95% CI 2.78-23.08). TEM defect closure was associated with lower LR on multivariate analysis (HR 0.19, 95% CI 0.06-0.59). Among 124 patients who underwent TEM for rectal adenocarcinoma, LR was 15.0% (95% CI 6.0-24.0) at three years. The first surveillance endoscopy had a 1.4% yield for low-risk patients (benign lesion, negative margins, and closed TEM defect) and 6.9% for all others. Conclusions LR at three years after TEM was 10.5% for benign polyps and 15.0% for adenocarcinomas. Early surveillance endoscopy can be considered low yield in some patients after TEM, which can be informative for shared decision-making regarding whether to proceed with early endoscopy in a low-risk subgroup of patients.

Optimizing Timing of Follow-Up Colonoscopy: A Pilot Cluster Randomized Trial of a Knowledge Translation Tool

BACKGROUND

Endoscopists have low adherence to guideline-recommended colonoscopy surveillance intervals. We performed a cluster-randomized single-blind pilot trial in Winnipeg, Canada, to assess the effectiveness of a newly developed digital application tool that computes guideline-recommended follow-up intervals.

METHODS

Participant endoscopists were randomized to either receive access to the digital application (intervention group) or not receive access (control group). Pathology reports and final recommendations for colonoscopies performed in the 1-4 months before randomization and 3-7 months postrandomization were extracted. Generalized estimating equation models were used to determine whether the access to the digital application predicted guideline congruence.

RESULTS

We included 15 endoscopists in the intervention group and 14 in the control group (of 42 eligible endoscopists in the city), with 343 patients undergoing colonoscopy before randomization and 311 postrandomization. Endoscopists who received the application made guideline-congruent recommendations 67.6% of the time before randomization and 76.1% of the time after randomization. Endoscopists in the control group made guideline-congruent recommendations 72.4% and 72.9% of the time before and after randomization, respectively. Endoscopists in the intervention group trended to have an increase in guideline adherence comparing postintervention with preintervention (odds ratio [OR]: 1.50, 95% confidence interval [CI] 0.82-2.74). By contrast, the control group had no change in guideline adherence (OR: 1.07, 95% CI 0.50-2.29). Endoscopists in the intervention group with less than median guideline congruence prerandomization had a significant increase in guideline-congruent recommendations postrandomization.

DISCUSSION

An application that provides colonoscopy surveillance intervals may help endoscopists with guideline congruence, especially those with a lower preintervention congruence with guideline recommendations ( ClincialTrials.gov number, NCT04889352).

Effectiveness of Standard Treatment for Stage 4 Colorectal Cancer: Traditional Management with Surgery, Radiation, and Chemotherapy

Colorectal cancer (CRC) is the second most common cause of cancer-related death in the United States comprising 7.9% of all new cancer diagnoses and 8.6% of all cancer deaths. The combined 5-year relative survival rate for all stages is 65.1% but in its most aggressive form, stage 4 CRC has a 5-year relative survival rate of just 15.1%. For most with stage 4 CRC, treatment is palliative not curative, with the goal to prolong overall survival and maintain an acceptable quality of life. The identification of unique cancer genomic and biologic markers allows patient-specific treatment options. Treatment of stage 4 CRC consists of systemic therapy with chemotherapeutic agents, surgical resection if feasible, potentially including resection of metastasis, palliative radiation in select settings, and targeted therapy toward growth factors. Despite advances in surgical and medical management, metastatic CRC remains a challenging clinical problem associated with poor prognosis and low overall survival.

Update on Targeted Therapy and Immunotherapy for Metastatic Colorectal Cancer

Metastatic colorectal cancer remains a deadly malignancy and is the third leading cause of cancer-related death. The mainstay of treatment for metastatic colorectal cancer is chemotherapy, but unfortunately, even with recent progress, overall survival is still poor. Colorectal cancer is a heterogeneous disease, and the underlying genetic differences among tumors can define the behavior and prognosis of the disease. Given the limitations of cytotoxic chemotherapy, research has focused on developing targeted therapy based on molecular subtyping. Since the early 2000s, multiple targeted therapies have demonstrated efficacy in treating metastatic colorectal cancer and have received FDA approval. The epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), and DNA mismatch repair pathways have demonstrated promising results for targeted therapies. As new gene mutations and proteins involved in the oncogenesis of metastatic colorectal cancer are identified, new targets will continue to emerge. We herein provide a summary of the updated literature regarding targeted therapies for patients with mCRC.

Tata Memorial Centre Evidence Based Management of Colorectal cancer

ABSTRACT

This review article examines the evidence-based management of colorectal cancers, focusing on topics characterized by ongoing debates and evolving evidence. To contribute to the scientific discourse, we intentionally exclude subjects with established guidelines, concentrating instead on areas where the current understanding is dynamic. Our analysis encompasses a thorough exploration of critical themes, including the evidence surrounding complete mesocolic excision and D3 lymphadenectomy in colon cancers. Additionally, we delve into the evolving landscape of perioperative chemotherapy in both colon and rectal cancers, considering its nuanced role in the context of contemporary treatment strategies. Advancements in surgical techniques are a pivotal aspect of our discussion, with an emphasis on the utilization of minimally invasive approaches such as laparoscopy and robotic surgery in both colon and rectal cancers, including advanced rectal cases. Moving beyond conventional radical procedures, we scrutinize the feasibility and implications of endoscopic resections for small tumors, explore the paradigm of organ preservation in locally advanced rectal cancers, and assess the utility of total neoadjuvant therapy in the current treatment landscape. Our final segment reviews pivotal trials that have significantly influenced the management of colorectal liver and peritoneal metastasis.

Exploring the Expression and Prognosis of Mismatch Repair Proteins and PD-L1 in Colorectal Cancer in a Chinese Cohort

Purpose

Exploring the expression and prognosis of mismatch repair proteins and PD-L1 in colorectal cancer.

Patients and Methods

A total of 272 patients with surgically resected CRC were enrolled in the study from January 2018 to May 2022 at Nanjing Drum Tower Hospital (The Affiliated Hospital of Nanjing University Medical School). Surgically resected samples were collected from patients along with general, clinicopathological, and imaging data for each patient. Immunohistochemistry (IHC) was used to detect expression of MSH2, MSH6, MLH1, and PMS2 proteins in tumor tissue. X-squared (X2) testing was performed to investigate the correlation between expression of MMR proteins and PD-L1 in CRC tumor tissues and clinicopathological characteristics. Correlation analysis was also used to compare the deletion of four MMR proteins in CRC tumor tissues. A survival curve and Log rank test were used to investigate the relationship between the expression of MMR proteins and PD-L1 with regard to CRC patient prognosis and survival.

Results

MMR protein expression deletion was correlated with tumor location, the degree of tissue differentiation, and TNM stage (P<0.05). PD-L1 expression was correlated with TNM stage (P<0.05). Correlation analysis of deletion of MMR protein isoform expression found that PMS2 deletion was significantly correlated with MLH1 deletion (P<0.05). Similarly, MSH2 deletion was significantly correlated with MSH6 deletion (P<0.05). PMS2 deletion was also found to be correlated with PD-L1 expression (P<0.05). Progression-free survival was found to be significantly longer in mismatch repair-proficient (pMMR) patients compared with mismatch repair-deficient (dMMR) patients.

Conclusion

Deletion of MMR proteins and expression of PD-L1 are closely related to clinicopathological characteristics and overall prognosis of CRC patients. This suggests the relevance of MMR and PD-L1 as potential biomarkers for treatment of CRC patients.

Single-organ pulmonary metastasis is a favorable prognostic factor in metastatic colorectal cancer patients treated with FOLFIRI and vascular endothelial growth factor inhibitors

BACKGROUND

Few studies have focused on the impact of single-organ pulmonary metastases on progression-free survival and overall survival in patients with metastatic colorectal cancer. Recognizing differences in prognosis and chemotherapeutic efficacy based on metastasized organs may help in optimizing treatment strategies. The exploratory study was conducted to evaluate the comparative clinical outcomes and prognoses of patients with metastatic colorectal cancer presenting with single-organ pulmonary metastases and treated with folinic acid, 5-fluorouracil, irinotecan, and vascular endothelial growth factor inhibitors as second-line chemotherapy.

METHODS

This retrospective study included 289 patients with metastatic colorectal cancer treated with second-line folinic acid, 5-fluorouracil, irinotecan, and vascular endothelial growth factor inhibitors. The response rate, disease control rate, progression-free survival, and overall survival were assessed in the participants.

RESULTS

Among the 289 patients enrolled, 26 (9.0%) had single-organ pulmonary metastasis with left-sided primary locations, lower levels of tumor markers at the initiation point of chemotherapy, a significantly higher disease control rate (96.2% vs. 76.7%, P = .02), and a longer progression-free survival (median 29.6 months vs. 6.1 months, P < .001) and overall survival (median 41.1 months vs. 18.7 months, P < .001) than patients with other forms of metastatic colorectal cancer. Multivariate analysis showed that single-organ pulmonary metastasis was an independent predictor of longer progression-free survival (hazard ratio 0.35, P = .00075) and overall survival (hazard ratio 0.2, P = .006).

CONCLUSION

Single-organ pulmonary metastasis was a strong predictor of progression-free survival and overall survival in patients with metastatic colorectal cancer treated with folinic acid, 5-fluorouracil, irinotecan, and vascular endothelial growth factor inhibitors as second-line chemotherapy; this provides preliminary evidence for medical guidelines and clinical decision-making on novel therapeutic strategies for these patients.

Integrated transcriptomics and proteomics data analysis identifies CDH17 as a key cell surface target in colorectal cancer

Immunotherapy development against colorectal cancer (CRC) is hindered by the lack of cell surface target highly expressed in cancer cells but with restricted presence in normal tissues to minimize off-tumor toxicities. In this in silico analysis, a longlist of genes (n = 13,488) expressed in CRCs according to the Human Protein Atlas (HPA) database were evaluated to shortlist for potential surface targets based on the following prerequisites: (i) Absent from the brain and lung tissues to minimize the likelihood of neurologic and pulmonary toxicities; (ii) Restricted expression profile in other normal human tissues; (iii) Genes that potentially encode cell surface proteins and; (iv) At least moderately expressed in CRC cases. Fifteen potential targets were shortlisted and subsequently ranked according to the combination of their transcript and protein expression levels in CRCs derived from multiple datasets (i.e. DepMap, TCGA, CPTAC-2, and HPA CRCs). The top-ranked target with the highest and homogenous expression in CRCs was cadherin 17 (CDH17). Downstream analysis of CRC transcriptomics and proteomics datasets showed that CDH17 was significantly correlated with carcinoembryonic antigen expression. Moreover, CDH17 expression was significantly lower in CRC cases with high microsatellite instability, as well as negatively associated with immune response gene sets and the expression of MHC class I and II molecules. CDH17 represents an optimal target for therapeutic development against CRCs, and this study provides a novel framework to identify key cell surface targets for therapeutic development against other malignancies.

Clinical outcomes of colonoscopic polypectomy with strategic surveillance colonoscopies in patients with 10 or more polyps

The clinical usefulness of repeat colonoscopic polypectomy in patients with numerous polyps has not been sufficiently determined. We aimed to analyze the clinical outcomes of colonoscopic polypectomy with surveillance colonoscopies in patients with ≥ 10 polyps. We reviewed the medical records of 152 patients who underwent polypectomy of ≥ 10 polyps at the baseline colonoscopy. We investigated polyp number, polyp size, polypectomy method, procedure time, and adverse events of the baseline colonoscopy. We also investigated the frequency and interval of surveillance colonoscopies and their findings. The mean number of polyps detected at the baseline colonoscopy was 20.0, of which 16.0 polyps were endoscopically resected. The mean size of the largest polyp was 13.4 mm. The mean procedure time was 54.9 min. Post-polypectomy bleeding occurred in 6 (3.9%) patients, all of whom were treated conservatively. No patients developed perforation. With an increasing number of surveillance colonoscopies, the number of detected polyps and the procedure time decreased. Surveillance colonoscopies identified colorectal cancer only in three patients (2.0%), all of which were mucosal cancers that could be curatively treated by polypectomy. Colonoscopic polypectomy with repeat surveillance colonoscopies is a clinically effective, efficient, and safe management option in patients with ≥ 10 polyps.

Complete response to third-line treatment with trifluridine/tipiracil (TAS-102) in stage IV colon adenocarcinoma

A clinical case of a 61-year-old female diagnosed with stage IV right colon adenocarcinoma (unresectable liver and multiple lymph node metastases at the time of diagnosis), Kirsten rat sarcoma viral oncogene homolog (KRAS), neuroblastoma rat sarcoma viral oncogene homolog (NRAS) and v-raf murine sarcoma viral oncogene homolog B (BRAF) wild-type, proficient mismatch repair (pMMR), in whom a complete response to the third-line of systemic treatment with trifluridine/tipiracil (TAS-102) was obtained. The complete response has been maintained for more than 2 years after its suspension.

Real-time artificial intelligence (AI)-aided endoscopy improves adenoma detection rates even in experienced endoscopists: a cohort study in Singapore

BACKGROUND

Colonoscopy is a mainstay to detect premalignant neoplastic lesions in the colon. Real-time Artificial Intelligence (AI)-aided colonoscopy purportedly improves the polyp detection rate, especially for small flat lesions. The aim of this study is to evaluate the performance of real-time AI-aided colonoscopy in the detection of colonic polyps.

METHODS

A prospective single institution cohort study was conducted in Singapore. All real-time AI-aided colonoscopies, regardless of indication, performed by specialist-grade endoscopists were anonymously recorded from July to September 2021 and reviewed by 2 independent authors (FHK, JL). Sustained detection of an area by the program was regarded as a "hit". Histology for the polypectomies were reviewed to determine adenoma detection rate (ADR). Individual endoscopist's performance with AI were compared against their baseline performance without AI endoscopy.

RESULTS

A total of 24 (82.8%) endoscopists participated with 18 (62.1%) performing ≥ 5 AI-aided colonoscopies. Of the 18, 72.2% (n = 13) were general surgeons. During that 3-months period, 487 "hits" encountered in 298 colonoscopies. Polypectomies were performed for 51.3% and 68.4% of these polypectomies were adenomas on histology. The post-intervention median ADR was 30.4% was higher than the median baseline polypectomy rate of 24.3% (p = 0.02). Of the adenomas excised, 14 (5.6%) were sessile serrated adenomas. Of those who performed ≥ 5 AI-aided colonoscopies, 13 (72.2%) had an improvement of ADR compared to their polypectomy rate before the introduction of AI, of which 2 of them had significant improvement.

CONCLUSIONS

Real-time AI-aided colonoscopy have the potential to improved ADR even for experienced endoscopists and would therefore, improve the quality of colonoscopy.

Identification of Biomarkers Associated with Liver Metastasis Progression from Colorectal Cancer Using Exosomal RNA Profiling

This study aimed to identify novel biomarkers for metastatic colorectal cancer progression using exosomal RNA expression profiling. The exosomal RNA expression profiles of 54 patients with mCRC were investigated. Exosomal RNA profiling was performed at the time of relapse immediately before metastasectomy and cancer recurrence or progression after metastasectomy. The up- and down-regulated RNA expression profiles were screened and analyzed using H-cluster, principle component analysis and gene ontology. The tissue expression profile of the liver metastases was compared with the GSE 41258 set using GSEA tools. We identified two distinctive biological process gene sets (IFNA and PCDB families) related to metastatic progression. The interferon-α response gene set was enriched, especially when the tumor volume was ≥1 cm3. CXCL10, CXCL11 and SAMD 9 mRNA were highly expressed in the plasma exosome samples of patients with mCRC to the liver. Furthermore, high expression of CXCL10 but not CXCL11 or SAMD9 was associated with a poor prognosis and shorter progression-free survival. Conclusions: Cancer-derived exosomal CXCL10 may be a novel biomarker for liver metastasis of mCRC and a potential target for the prevention and treatment of mCRC with liver metastasis.

Hidden local recurrence of colorectal adenocarcinoma diagnosed by endoscopic ultrasound: A case series

BACKGROUND

Almost half of the patients with colorectal cancer (CRC) will experience local-regional recurrence after standard surgical excision. Many local recurrences of colorectal cancer (LRCC) do not grow intraluminally, and some may be covered by a normal mucosa so that they could be missed by colonoscopy. Early detection is crucial as it offers a chance to achieve curative reoperation. Endoscopic ultrasound (EUS) is mainly used in CRC staging combined with cross-section imaging study. EUS can provide an accurate assessment of sub-mucosal lesions by demarcating the originating wall layer and evaluating its echostructure. EUS fine-needle aspiration (FNA) provides the required tissue examination and confirms the diagnosis.

CASE SUMMARY

We report a series of five cases referred to surveillance for LRCC with negative colonoscopy and/or negative endoscopic biopsies. EUS-FNA confirmed LRCC implanted deep into the third and fourth wall layer with normal first and second layer.

CONCLUSION

Assessment for LCRR is still problematic and may be very tricky. EUS and EUS-FNA may be useful tools to exclude local recurrence.

Measuring and Improving Quality of Colonoscopy for Colorectal Cancer Screening

Colorectal cancer (CRC) is largely preventable, yet it remains a major public health issue as it is the third most common and deadly malignancy in the United States. While there are many ways to screen for CRC, colonoscopy remains the gold standard as it is the only test that is both cancer-detecting and cancer-preventing through removal of precancerous polyps. Through identifying and removing neoplastic lesions, colonoscopy reduces CRC incidence by 31%-91% and CRC mortality by 65%-88%. However, colonoscopy is not an infallible test-there is a chance for missed lesions during the exam and there is substantial variation in outcomes among endoscopists. To enhance the quality of colonoscopic exams, and ultimately to improve CRC outcomes, quality indicators have been developed for measuring endoscopists' performance. In this review, we describe the colonoscopic quality indicators and benchmarks recommended by the American Society for Gastrointestinal Endoscopy/American College of Gastroenterology Task Force on Quality in Endoscopy for screening colonoscopies in average-risk individuals. Measuring and monitoring endoscopists' performance on these measures are critical first steps in striving toward conducting high quality exams. We also review the evidence for interventions that aim to improve critical measures including adenoma detection rate, withdrawal time, cecal intubation, and bowel preparation quality. Finally, we provide a preview of the forthcoming Advancing Care for Appropriate Colon Health Merit-Based Incentive Payment System Value Pathway by the Centers for Medicare & Medicaid Services and its potential impact on clinical practice.

Design and verification of individualized follow-up strategy of colonoscopy for postoperative patients with colorectal cancer

BACKGROUND

Current guidelines do not establish an individual scheme for surveillance colonoscopy in postoperative colorectal cancer (CRC) patients.

AIMS

The purpose of the study was to screen possible risk factors for the development of metachronous adenoma in postoperative CRC patients and to develop a risk prediction model and verify it.

METHODS

Consecutive postoperative patients with CRC were enrolled from April 2007 to December 2013 as the derivation group. Baseline data of patients and clinicopathological features of the tumor were collected, logistic regression analysis was performed, and clinical model was established and was verified internally. The model was externally validated in an independent cohort (validation group) from January 2014 to October 2017 in the same hospital.

RESULTS

A total of 734 patients were included, with average (64.6 ± 11.5) years old. The overall incidence of metachronous adenoma was 35.4%. There was no significant difference in the incidence of metachronous adenoma between the derivation group and validation group (P > 0.05). Age, diabetes mellitus, right colon cancer, moderately to poorly differentiated adenocarcinoma and synchronous adenoma were independent risk factors for metachronous adenoma. The C-index of the metachronous adenoma line chart model was 0.932, and the index decreased by 0.022 after internal verification. The C-index of external validation was 0.910. The Hosmer-Lemeshow test showed that the P value of metachronous adenoma risk prediction model was 0.247.

CONCLUSIONS

Individual surveillance strategies should be designed for postoperative patients with CRC. For high-risk patients, it is appropriate to undergo more than two colonoscopies in 36 months after operation.

Large polyps: Pearls for the referring and receiving endoscopist

Polyps are precursors to colorectal cancer, the third most common cancer in the United States. Large polyps, i.e.,, those with a size ≥ 20 mm, are more likely to harbor cancer. Colonic polyps can be removed through various techniques, with the goal to completely resect and prevent colorectal cancer; however, the management of large polyps can be relatively complex and challenging. Such polyps are generally more difficult to remove en bloc with conventional methods, and depending on level of expertise, may consequently be resected piecemeal, leading to an increased rate of incomplete removal and thus polyp recurrence. To effectively manage large polyps, endoscopists should be able to: (1) Evaluate the polyp for characteristics which predict high difficulty of resection or incomplete removal; (2) Determine the optimal resection technique (e.g., snare polypectomy, endoscopic mucosal resection, endoscopic submucosal dissection, etc.); and (3) Recognize when to refer to colleagues with greater expertise. This review covers important considerations in this regard for referring and receiving endoscopists and methods to best manage large colonic polyps.

BESPOKE study protocol: a multicentre, prospective observational study to evaluate the impact of circulating tumour DNA guided therapy on patients with colorectal cancer

INTRODUCTION

Colorectal cancer (CRC) is a highly prevalent disease, wherein, ~30%-40% of patients with CRC relapse postresection. In some patients with CRC, adjuvant chemotherapy can help delay recurrence or be curative. However, current biomarkers show limited clinical utility in determining if/when chemotherapy should be administered, to provide benefit. Circulating tumour DNA (ctDNA) can measure molecular residual disease (MRD) and relapse with high specificity and sensitivity. This study protocol investigates the clinical utility of ctDNA for optimal use of adjuvant chemotherapy in patients with surgically resected CRC and to detect early disease progression in the surveillance setting.

METHODS AND ANALYSIS

This is a multicentre prospective, observational cohort study. A total of 2000 stage I-IV patients will be enrolled in up to 200 US sites, and patients will be followed for up to 2 years with serial ctDNA analysis, timed with the standard-of-care visits. The primary endpoints are to observe the impact of bespoke ctDNA testing on adjuvant treatment decisions and to measure CRC recurrence rates while asymptomatic and without imaging correlate. The secondary endpoints are MRD clearance rate (MRD+ to MRD-) during or after adjuvant chemotherapy, percentage of patients that undergo surgery for oligometastatic recurrence, survival of MRD-negative patients treated with adjuvant chemotherapy versus no adjuvant chemotherapy (active surveillance), overall survival, examine the number of stage I CRC that have recurrent disease detected postsurgery, and patient-reported outcomes.

ETHICS AND DISSEMINATION

This study has received ethical approval from the Advarra Institutional Review Board (IRB) protocol: Natera-20-041-NCP/3766.01, BESPOKE Study of ctDNA Guided Therapy in Colorectal Cancer (BESPOKE CRC) (Pro00041473) on 10 June 2021. Data protection and privacy regulations will be strictly observed in the capturing, forwarding, processing and storing of patients' data. Publication of any study results will be approved by Natera in accordance with the site-specific contract.

TRIAL REGISTRATION NUMBER

NCT04264702.

Nanotechnology in Colorectal Cancer for Precision Diagnosis and Therapy

Colorectal cancer (CRC) is the third most frequently occurring tumor in the human population. CRCs are usually adenocarcinomatous and originate as a polyp on the inner wall of the colon or rectum which may become malignant in the due course of time. Although the therapeutic options of CRC are limited, the early diagnosis of CRC may play an important role in preventive and therapeutic interventions to decrease the mortality rate. The CRC-affected tissues exhibit several molecular markers that may be exploited as the novel strategy to develop newer approaches for the treatment of the disease. Nanotechnology consists of a wide array of innovative and astonishing nanomaterials with both diagnostics and therapeutic potential. Several nanomaterials and nano formulations such as Carbon nanotubes, Dendrimer, Liposomes, Silica Nanoparticles, Gold nanoparticles, Metal-organic frameworks, Core-shell polymeric nano-formulations, Nano-emulsion System, etc can be used to targeted anticancer drug delivery and diagnostic purposes in CRC. The light-sensitive photosensitizer drugs loaded gold and silica nanoparticles can be used to diagnose as well as the killing of CRC cells by the targeted delivery of anticancer drugs to cancer cells. This review is focused on the recent advancement of nanotechnology in the diagnosis and treatment of CRC.

Colorectal cancer screening and surveillance strategy for patients with Diamond Blackfan anemia: Preliminary recommendations from the Diamond Blackfan Anemia Registry

Diamond Blackfan anemia (DBA) is a rare inherited bone marrow failure syndrome characterized by red cell failure, congenital anomalies, poor linear growth, and cancer predisposition. Two previous analyses from the Diamond Blackfan Anemia Registry have quantified DBA as a cancer predisposition syndrome of moderate cancer penetrance. Patients with DBA have a 4.8-fold higher relative risk of developing cancer with an overall cumulative incidence of 13.7% by age 45 years. The two most prevalent solid tumors are colorectal cancer (CRC) and osteogenic sarcoma. Current and evolving data support the institution of cancer screening and surveillance strategies for CRC in DBA.

Different position from traditional left lateral for colonoscopy? A meta-analysis and systematic review of randomized control trials

BACKGROUND

Colonoscopy requires the intubation of the cecum for screening of colorectal diseases. The conventional position used for colonoscopy is the left lateral position (LLP). However, alternative positions have also been utilized to enhance the success of intubation. Thus, the aim of this study was to perform a meta-analysis of the different positions to determine the effectiveness of the individual positions for successful colonoscopy.

METHODS

Medline, Embase and Cochrane trials electronic databases were searched for studies on colonoscopy positions. The primary outcome was defined as the cecal intubation rate. Pooled risk ratios (RR) and 95% confidence intervals (CI) for the rates of cecal intubation were estimated. Secondary outcomes such as the cecal intubation time and adenoma detection rate were further analyzed qualitatively.

RESULTS

After reviewing 644 identified records, 7 randomized control trials (RCT) studies were included. No significant difference was observed in either comparisons, between the LLP vs. supine position (SP) (RR = 1.01, 95% CI, 0.98 to 1.04, P = 0.55) or the LLP vs. prone position (PP) (RR = 1.02, 95% CI, 0.98 to 1.06, P = 0.27).

CONCLUSIONS

Amidst available literature, the use of other positions can be considered when performing colonoscopy. These further highlights that the existential practice is based predominantly on familiarity instead of evidence-based-research.

Diagnosis and Treatment of Metastatic Colorectal Cancer: A Review

IMPORTANCE

Colorectal cancer (CRC) is the third most common cause of cancer mortality worldwide with more than 1.85 million cases and 850 000 deaths annually. Of new colorectal cancer diagnoses, 20% of patients have metastatic disease at presentation and another 25% who present with localized disease will later develop metastases.

OBSERVATIONS

Colorectal cancer is the third most common cause of cancer mortality for men and women in the United States, with 53 200 deaths projected in 2020. Among people diagnosed with metastatic colorectal cancer, approximately 70% to 75% of patients survive beyond 1 year, 30% to 35% beyond 3 years, and fewer than 20% beyond 5 years from diagnosis. The primary treatment for unresectable metastatic CRC is systemic therapy (cytotoxic chemotherapy, biologic therapy such as antibodies to cellular growth factors, immunotherapy, and their combinations.) Clinical trials completed in the past 5 years have demonstrated that tailoring treatment to the molecular and pathologic features of the tumor improves overall survival. Genomic profiling to detect somatic variants is important because it identifies the treatments that may be effective. For the 50% of patients with metastatic CRC with KRAS/NRAS/BRAF wild-type tumors, cetuximab and panitumumab (monoclonal antibodies to the epithelial growth factor receptor [EGFR]), in combination with chemotherapy, can extend median survival by 2 to 4 months compared with chemotherapy alone. However, for the 35% to 40% of patients with KRAS or NRAS sequence variations (formerly termed mutations), effective targeted therapies are not yet available. For the 5% to 10% with BRAF V600E sequence variations, targeted combination therapy with BRAF and EGFR inhibitors extended overall survival to 9.3 months, compared to 5.9 months for those receiving standard chemotherapy. For the 5% with microsatellite instability (the presence of numerous insertions or deletions at repetitive DNA units) or mismatch repair deficiency, immunotherapy may be used in the first or subsequent line and has improved treatment outcomes with a median overall survival of 31.4 months in previously treated patients.

CONCLUSIONS AND RELEVANCE

Advances in molecular profiling of metastatic CRC facilitate the ability to direct treatments to the biologic features of the tumor for specific patient subsets. Although cures remain uncommon, more patients can anticipate extended survival. Genomic profiling allows treatment selection so that more patients derive benefit and fewer are exposed to toxicity from ineffective therapies.

Estimating Population-Based Recurrence Rates of Colorectal Cancer over Time in the United States

BACKGROUND

Population-based metastatic recurrence rates for patients diagnosed with nonmetastatic colorectal cancer cannot be estimated directly from population-based cancer registries because recurrence information is not reported. We derived population-based colorectal cancer recurrence rates using disease-specific survival data based on our understanding of the colorectal cancer recurrence-death process.

METHODS

We used a statistical continuous-time multistate survival model to derive population-based annual colorectal cancer recurrence rates from 6 months to 10 years after colorectal cancer diagnosis using relative survival data from the Surveillance, Epidemiology, and End Results Program. The model was based on the assumption that, after 6 months of diagnosis, all colorectal cancer-related deaths occur only in patients who experience a metastatic recurrence first, and that the annual colorectal cancer-specific death rate among patients with recurrence was the same as in those diagnosed with de novo metastatic disease. We allowed recurrence rates to vary by post-diagnosis time, age, stage, and location for two diagnostic time periods.

RESULTS

In patients diagnosed in 1975-1984, annual recurrence rates 6 months to 5 years after diagnosis ranged from 0.054 to 0.060 in stage II colon cancer, 0.094 to 0.105 in stage II rectal cancer, and 0.146 to 0.177 in stage III colorectal cancer, depending on age. We found a statistically significant decrease in colorectal cancer recurrence among patients diagnosed in 1994-2003 compared with those diagnosed in 1975-1984 for 6 months to 5 years after diagnosis (hazard ratios between 0.43 and 0.70).

CONCLUSIONS

We derived population-based annual recurrence rates for up to 10 years after diagnosis using relative survival data.

IMPACT

Our estimates can be used in decision-analytic models to facilitate analyses of colorectal cancer interventions that are more generalizable.

Appraisal of 5-year recurrence-free survival after surgery in pancreatic ductal adenocarcinoma

BACKGROUND/PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is regarded as incurable, with a limited survival rate after curative resection. The aim of this study was to explore long-term survival and late recurrence of PDAC after surgery.

METHODS

Medical data of 859 patients who underwent resection between 1995 and 2014 were retrospectively examined. The clinicopathological features of the 5-year recurrence-free survivors and the patients with recurrent disease after 5 years were investigated separately.

RESULTS

Among the 768 patients who were finally included in this study, elevated CA 19-9, tumor size, poor differentiation, and positive lymph node metastasis were associated with recurrence. In 89 patients with 5-year RFS, age, tumor size, differentiation, and lymph node metastasis were statistically significant predictive factors. Among these patients, disease relapse occurred in 11 patients; age was the only difference compared to those who remained free of recurrence.

CONCLUSIONS

Most prognosticators failed to predict the risk of recurrence in the 5 years following surgery for PDAC, and recurrence can occur even at time points up to 100 months. Therefore, cure of PDAC cannot be guaranteed by a 5-year recurrence-free interval, and further studies into the inherent nature of PDAC are needed to develop adequate surveillance systems which may lead to improvements in survival.

Case report of surgical management of a locally invasive colostomy adenocarcinoma

INTRODUCTION

This case report involves the presentation and management of a locally invasive adenocarcinoma at the site of a colostomy in a patient with multiple comorbidities and anatomic constraints.

PRESENTATION OF CASE

63 year-old woman with a complicated medical and surgical history, including imperforate anus and permanent colostomy, who presented with a fungating mass at the site of her colostomy. Evaluation revealed a locally invasive adenocarcinoma requiring surgical management for symptom control and oncologic treatment.

DISCUSSION

Due to the patient's medical comorbidities, body habitus, prior surgery, prior radiation and locally invasive cancer, there were numerous physiologic and anatomic issues that required a multi-disciplinary approach. Specifically, consideration of the patient's prior radiation to the left chest, history of cystectomy and ileal conduit, history of prior colon resection, as well as her short stature and severe kyphosis required input from urology, plastic surgery and colorectal surgery for operative planning. The patient's chronic renal insufficiency, recurrent urinary tract infections and history of thromboembolic disease further complicated her perioperative management. Oncologic resection with wide local excision at the skin and abdominal wall were performed with mass closure of the midline and peristomal abdominoplasty, using mesh underlay. The patient's postoperative course was complicated by gastric outlet obstruction and recurrent urosepsis.

CONCLUSIONS

Patients with chronic colostomies require colon cancer screening similar to their non-stoma peers, in accordance with national guidelines. Oncologic resection of cancers involving colostomies is feasible, but may require multi-disciplinary planning to manage complicated anatomic concerns.

Computed Tomography Colonography Versus Standard Optical Colonoscopy for the Detection of Colorectal Polyp in Patients Who Faced Curative Surgery for Colorectal Cancer: A Diagnostic Performance Study

Data regarding computed tomography colonography, standard optical colonoscopy, and enhanced colonoscopy/histopathology at 1-year after surgery and at 6-month intervals for the next 2 years of 345 patients who faced curative surgery for colorectal cancer were included in this analysis. Computed tomography colonography and standard optical colonoscopy both detected 298 polyps as suspicious. With reference to enhanced colonoscopy/histopathology, sensitivities for the detection of any polyps for computed tomography colonography and standard optical colonoscopy were 0.952 and 0.906, while, accuracies were 0.783 and 0.641, respectively. Computed tomography colonography may be a sensitive and accurate surveillance tool for colorectal cancer patients.

Surveillance Colonoscopy in Older Stage I Colon Cancer Patients and the Association With Colon Cancer-Specific Mortality

OBJECTIVES

Guideline-issuing groups differ regarding the recommendation that patients with stage I colon cancer receive surveillance colonoscopy after cancer-directed surgery. This observational comparative effectiveness study was conducted to evaluate the association between surveillance colonoscopy and colon cancer-specific mortality in early stage patients.

METHODS

This was a retrospective cohort study of the Surveillance, Epidemiology, and End Results database combined with Medicare claims. Surveillance colonoscopy was assessed as a time-varying exposure up to 5 years after cancer-directed surgery with the following groups: no colonoscopy, one colonoscopy, and ≥ 2 colonoscopies. Inverse probability of treatment weighting was used to balance covariates. The time-dependent Cox regression model was used to obtain inverse probability of treatment weighting-adjusted hazard ratios (HRs), with 95% confidence intervals (CIs) for 5- and 10-year colon cancer, other cancer, and noncancer causes of death.

RESULTS

There were 8,783 colon cancer cases available for analysis. Overall, compared with patients who received one colonoscopy, the no colonoscopy group experienced an increased rate of 10-year colon cancer-specific mortality (HR = 1.63; 95% CI 1.31-2.04) and noncancer death (HR = 1.36; 95% CI 1.25-1.49). Receipt of ≥ 2 colonoscopies was associated with a decreased rate of 10-year colon cancer-specific death (HR = 0.60; 95% CI 0.45-0.79), other cancer death (HR = 0.68; 95% CI 0.53-0.88), and noncancer death (HR = 0.69; 95% CI 0.62-0.76). Five-year cause-specific HRs were similar to 10-year estimates.

DISCUSSION

These results support efforts to ensure that stage I patients undergo surveillance colonoscopy after cancer-directed surgery to facilitate early detection of new and recurrent neoplastic lesions.

Undisclosed payments by pharmaceutical and medical device manufacturers to authors of endoscopy guidelines in the United States

BACKGROUND AND AIMS

Payments from pharmaceutical and medical device manufacturers to authors of clinical practice guidelines (CPGs) may influence practice recommendations. It is therefore important to evaluate the completeness of financial conflict of interest (FCOI) declarations among CPG authors.

METHODS

We performed a cross-sectional analysis of industry payments to authors of endoscopy guidelines published by 5 GI societies between 2014 and 2017. For each author we identified payments using the disclosure section of CPGs and the Centers for Medicare & Medicaid Services Open Payments (CMS-OP) database. We calculated the prevalence, monetary value, and type of declared and undeclared payments among authors. Payments were assessed for the calendar year of and before publication.

RESULTS

Thirty-seven CPGs were included in the analysis comprising 569 author entries (91 unique individuals; 66.43% men, 92.6% physicians, 66.4% academically affiliated). Four hundred fifty-one episodes (79%) involved FCOIs, 451 (79%) had undisclosed FCOIs in the CMS-OP, and 445 (77%) had FCOIs relevant to a CPG recommendation. The median undisclosed payment value was $4807.26 (interquartile range, $334.84-$20,579.75). Male authors (odds ratio, 2.23; 95% confidence interval, 1.47-3.39) and academically affiliated authors (odds ratio, 8.87; 95% confidence interval, 5.57-14.13) were significantly more likely to have undeclared payments (P < .001). No CPGs met all National Academy of Medicine criteria.

CONCLUSIONS

Recognizing concerns about the accuracy of the CMS-OP, there are substantial discrepancies between industry-reported payments and author self-disclosure. Additionally, there is a high prevalence of undisclosed payments by pharmaceutical and medical device manufacturers to these authors. Given the potential impact of these discrepancies and undisclosed payments on CPGs, more accurate reporting and alternative strategies for managing FCOI are needed.

Yield of Surveillance Colonoscopies 1 Year After Curative Surgical Colorectal Cancer Resections

BACKGROUND & AIMS

Endoscopic surveillance after curative colorectal cancer (CRC) resection is routine. However, there is controversy whether the 1-year interval between preoperative and postoperative colonoscopy is justified owing to improved colonoscopy standards. We aimed to assess the yield of surveillance colonoscopies 1 year after CRC surgery.

METHODS

We performed a retrospective cohort study of 572 patients (54.9% male; mean age, 66.2 ± 9.9 y), who underwent curative surgical resection of a first CRC from June 2013 through April 2016 in the Northwest region of The Netherlands. Patients were included if a complete clearing colonoscopy was performed before surgery and the interval between the preoperative and postoperative colonoscopy was 12 months (range, 6-20 mo), conforming to Dutch guidelines. The primary outcome of the study was the yield of CRC at the surveillance colonoscopy performed 1 year after curative resection. A secondary outcome was the yield of advanced neoplasia.

RESULTS

After a mean surveillance interval of 13.7 months (±2.8 mo), 10 of 572 patients (1.7%; 95% CI, 0.7%-2.8%) received a diagnosis of CRC. Of these, 5 CRCs were apparently metachronous cancers (3 were stage III or IV) and 5 were recurrences at the anastomosis (1 was stage IV). In 11.4% of patients (95% CI, 8.9%-13.8%), advanced neoplasia was detected at the 1-year follow-up colonoscopy. Synchronous advanced neoplasia at baseline colonoscopy was a risk factor for detection of advanced neoplasia at the follow-up colonoscopy (odds ratio, 2.2; 95% CI, 1.3-3.8; P ≤ .01).

CONCLUSIONS

Despite high colonoscopy quality, the yield of CRC at surveillance colonoscopy 1 year after CRC resection was 1.7%. These were metachronous CRCs and recurrences, often of advanced stage. The high yield justifies the recommendation of a 1-year surveillance interval after surgical CRC resection.

Current strategies for malignant pedunculated colorectal polyps

Despite significant advances in imaging techniques, the incidence of colorectal cancer has been increasing in recent years, with many cases still being diagnosed in advanced stages. Early detection and accurate staging remain the main factors that lead to a decrease in the cost and invasiveness of the curative techniques, significantly improving the outcome. However, the diagnosis of pedunculated early colorectal malignancy remains a current challenge. Data on the management of pedunculated cancer precursors, apart from data on nonpolypoid lesions, are still limited. An adequate technique for complete resection, which provides the best long-term outcome, is mandatory for curative intent. In this context, a discussion regarding the diagnosis of malignancy of pedunculated polyps, separate from non-pedunculated variants, is necessary. The purpose of this review is to provide a critical review of the most recent literature reporting the different features of malignant pedunculated colorectal polyps, including diagnosis and management strategies.

Assessment of Pharmaceutical Company and Device Manufacturer Payments to Gastroenterologists and Their Participation in Clinical Practice Guideline Panels

IMPORTANCE

Payments from pharmaceutical and device manufacturers to physicians may influence the advice physicians give patients and peers.

OBJECTIVES

To investigate the nature and amounts of monetary and other benefits that gastroenterologists received and to determine the participation of those receiving benefits in the formulation of clinical practice guidelines.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study analyzed information from the Centers for Medicare & Medicaid Services Open Payments database, including all reports about payments that pharmaceutical and device manufacturers gave to adult or pediatric gastroenterologists in 2016. PubMed was used to examine the professional affiliations and publication records of top payment recipients. Panelists of clinical guidelines who also received personal financial rewards listed in the Open Payments database were identified.

MAIN OUTCOMES AND MEASURES

Payments made to gastroenterologists by pharmaceutical company and device manufacturers.

RESULTS

Of 15 497 gastroenterologists, 13 467 (86.9%) received a total of 432 463 payments accounting for a total expenditure of $67 144 862. Direct financial payments for consultations, talks, or other services were made to 2055 physicians and were responsible for 4.2% of payments (18 179 of 432 463), but for 62.7% of total expenditures ($42 086 207 of $67 144 862). Although a significant number of submissions were for food and beverages, they constituted only a small amount of total expenditure. For gastroenterologists treating adult patients, 10 products were linked to 63.8% of payments (11 221 of 17 588) related to direct financial rewards and 37.1% of the total expenditures ($24 892 643 of $67 144 862). Twenty-nine of 36 clinical practice guidelines included panelists who had received honoraria or consultation fees from industry sources, with amounts exceeding $10 000 in 8 of them (22%).

CONCLUSIONS AND RELEVANCE

Most gastroenterologists accept meals or gifts from industry, with 2055 of 15 497 gastroenterologists receiving direct payments and 8 of 36 clinical practice guidelines panelists having received more than $10 000. Considering the known impact of such benefits on prescribing patterns and other professional behaviors, policy makers should consider revising regulations governing interactions with industry and disclosure formats alerting others to their potential biasing impact.

Rectal Cancer in 2018: A Primer for the Gastroenterologist

The rectum has distinctive anatomic and physiologic features, which increase the risk of local spread and recurrence among rectal cancers as compared to colon cancers. Essential to the management of rectal cancers is accurate endoscopic localization as well as preoperative imaging assessment of local and distant disease. Successful oncologic care is multidisciplinary including input from Gastroenterologists, Surgeons, Medical and Radiation Oncologists, Radiologists, and Pathologists. Extensive planning of curative intent is mandatory as failures of upfront treatment present great long‐term difficulty for patients and caregivers. Local recurrences are frequently associated with major morbidity including bowel and urinary obstruction, severe pain, and significantly diminished quality of life. Distant recurrence is associated with lower survival. Over the last two decades, there have been many advances in diagnostic imaging techniques as well as surgical techniques including transanal endoscopic microsurgery for very early stage cancers. Progress in curative management paradigms includes shorter courses of preoperative radiotherapy and chemotherapy doublet paradigms for perioperative treatment. This review describes the diagnosis, workup, and multimodality curative intent treatment of rectal cancers. It is emphasized that success begins in the hands and eyes of the gastroenterologist.

Comparison of the diagnostic efficiency for local recurrence of rectal cancer using CT, MRI, PET and PET-CT: A systematic review protocol

BACKGROUND

The risk of local recurrence (LR) continues to threat patients with rectal cancer after surgery or chemoradiotherapy. The main reason is that there is frequently extensive scarring and reactive changes after radiotherapy and resection. Thus, the diagnosis of LR can be challenging. There are different imaging modalities that have been used in the follow-up of rectal cancer, including computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), and positron emission tomography-computed tomography (PET-CT) in clinical practice.

METHODS

We will systematically search PubMed, EMBASE, the Cochrane Library, and Chinese Biomedical Literature Database for diagnostic trials using CT, MRI, PET, and PET-CT to detect LR of rectal cancer in April, 2018. Two review authors will independently screen titles and abstracts for relevance, assess full texts for inclusion, and carry out data extraction and methodological quality assessment using the QUADAS-2 tool. We will use bivariate meta-analysis to estimate summary sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of CT, MRI, PET, and PET-CT, as well as different sequences of MRI. For each index test, estimates of sensitivity and specificity from each study will be plotted in summary receive operating curve space and forest plots will be constructed for visual examination of variation in test accuracy. We will perform meta-analyses using the hierarchical summary receiver-operating characteristic model to produce summary estimates of sensitivity and specificity. Then, head-to-head and indirect comparison meta-analyses will be carried out.

DISCUSSION

This review will help determine the diagnostic accuracy of CT, MRI, PET, and PET-CT for the diagnosis of patients with LR of rectal cancer.

ETHICS AND DISSEMINATION

Ethics approval and patient consent are not required, as this study is a systematic review.

PROSPERO REGISTRATION NUMBER

CRD42018104918.

Clinical Practice Guideline on Screening for Colorectal Cancer in Individuals With a Family History of Nonhereditary Colorectal Cancer or Adenoma: The Canadian Association of Gastroenterology Banff Consensus

BACKGROUND & AIMS

A family history (FH) of colorectal cancer (CRC) increases the risk of developing CRC. These consensus recommendations developed by the Canadian Association of Gastroenterology and endorsed by the American Gastroenterological Association, aim to provide guidance on screening these high-risk individuals.

METHODS

Multiple parallel systematic review streams, informed by 10 literature searches, assembled evidence on 5 principal questions around the effect of an FH of CRC or adenomas on the risk of CRC, the age to initiate screening, and the optimal tests and testing intervals. The GRADE (Grading of Recommendation Assessment, Development and Evaluation) approach was used to develop the recommendations.

RESULTS

Based on the evidence, the Consensus Group was able to strongly recommend CRC screening for all individuals with an FH of CRC or documented adenoma. However, because most of the evidence was very-low quality, the majority of the remaining statements were conditional ("we suggest"). Colonoscopy is suggested (recommended in individuals with ≥2 first-degree relatives [FDRs]), with fecal immunochemical test as an alternative. The elevated risk associated with an FH of ≥1 FDRs with CRC or documented advanced adenoma suggests initiating screening at a younger age (eg, 40-50 years or 10 years younger than age of diagnosis of FDR). In addition, a shorter interval of every 5 years between screening tests was suggested for individuals with ≥2 FDRs, and every 5-10 years for those with FH of 1 FDR with CRC or documented advanced adenoma compared to average-risk individuals. Choosing screening parameters for an individual patient should consider the age of the affected FDR and local resources. It is suggested that individuals with an FH of ≥1 second-degree relatives only, or of nonadvanced adenoma or polyp of unknown histology, be screened according to average-risk guidelines.

CONCLUSIONS

The increased risk of CRC associated with an FH of CRC or advanced adenoma warrants more intense screening for CRC. Well-designed prospective studies are needed in order to make definitive evidence-based recommendations about the age to commence screening and appropriate interval between screening tests.

The added clinical value of performing CT colonography in patients with obstructing colorectal carcinoma

Background

A small percentage of incomplete optical colonoscopies (OCs) are the result of an obstructing tumor. According to current guidelines, CT colonography (CTC) is performed to prevent missing a synchronous tumor. The aim of this study was to evaluate how frequently a synchronous tumor was found on CTC and how often this led to a change in the surgical plan.

Methods

In this retrospective study, a total of 267 patients underwent CTC after an incomplete OC as a result of an obstructing colorectal carcinoma (CRC). Among them, 210 patients undergoing surgery met the inclusion criteria and were included in the analysis. The OC report, CTC report and surgical report of these patients were retrospectively evaluated for the presence of synchronous tumors using surgery and post-operative colonoscopy as the gold standard.

Results

Six of the 210 patients (2.9%) showed signs of a synchronous CRC proximal to the obstructing tumor on CTC. In three of these patients, a synchronous CRC was confirmed during surgery. All these tumors caused a change in the surgical plan. Three out of the six tumors found on CTC were found to be large, non-malignant polyps. All these polyps were located in the same segment as the obstructing tumor and therefore did not alter the surgical plan.

Conclusion

In patients with obstructing CRC, the frequency of synchronous CRCs proximal to this lesion is low. Performing a CTC leads to a change in surgical plan based on the presence of these synchronous tumors in 1.4% of the cases. CTC should be employed as a one-stop shop in patients with an obstructing CRC.

Patterns of follow up and survivorship care for people with colorectal cancer in new South Wales, Australia: a population-based survey

Background

The incidence and survival rates for colorectal cancer in Australia are among the highest in the world. With population growth and ageing there are increasing numbers of colorectal cancer survivors in the community, yet little is known of their ongoing follow up and survivorship care experiences. This study investigated patterns and predictors of follow up and survivorship care received and recommended for adults with colorectal cancer in New South Wales (NSW), Australia.

Methods

Cross-sectional analysis within the NSW Bowel Cancer Care Survey, a population-based cohort of adults diagnosed with colorectal cancer between April 2012 and May 2013 in NSW. One year after diagnosis, participants completed a study specific questionnaire about their follow up and survivorship care experience and plans. Logistic regression was used to identify independent predictors of guideline-recommended care.

Results

Of 1007 eligible people, 560 (56%) participated in the NSW Bowel Cancer Care Survey with 483 (86% of study participants, 48% of invited sample) completing the survivorship survey. Among these 483 participants, only 110 (23%, 95% Confidence Interval CI 19–27%) had received a written follow up plan, with this more common among migrants, non-urban dwellers and those with little experience of the health system. Of 379 (78%) people treated with curative intent, most were receiving ongoing colorectal cancer follow up from multiple providers with 28% (23–32%) attending three or more different doctors. However, less than half had received guideline-recommended follow-up colonoscopy (46%, CI 41–51%) or carcino-embryonic antigen assay (35%, CI 30–40%). Socio-economic advantage was associated with receipt of guideline-recommended care. While participants reported high interest in improving general health and lifestyle since their cancer diagnosis, few had received advice about screening for other cancers (24%, CI 19–28%) or assistance with lifestyle modification (30%, CI 26–34%). Less than half (47%, CI 43–52%) had discussed their family’s risk of cancer with a doctor since their diagnosis.

Conclusions

Survivorship care was highly variable, with evident socioeconomic disparities and missed opportunities for health promotion.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4297-6) contains supplementary material, which is available to authorized users.

2017 WSES guidelines for the management of iatrogenic colonoscopy perforation

Iatrogenic colonoscopy perforation (ICP) is a severe complication that can occur during both diagnostic and therapeutic procedures. Although 45–60% of ICPs are diagnosed by the endoscopist while performing the colonoscopy, many ICPs are not immediately recognized but are instead suspected on the basis of clinical signs and symptoms that occur after the endoscopic procedure. There are three main therapeutic options for ICPs: endoscopic repair, conservative therapy, and surgery. The therapeutic approach must vary based on the setting of the diagnosis (intra- or post-colonoscopy), the type of ICP, the characteristics and general status of the patient, the operator’s level of experience, and surgical device availability.

Although ICPs have been the focus of numerous publications, no guidelines have been created to standardize the management of ICPs. The aim of this article is to present the World Society of Emergency Surgery (WSES) guidelines for the management of ICP, which are intended to be used as a tool to promote global standards of care in case of ICP. These guidelines are not meant to substitute providers’ clinical judgment for individual patients, and they may need to be modified based on the medical team’s level of experience and the availability of local resources.

Colorectal adenoma and cancer detection based on altered methylation pattern of SFRP1, SFRP2, SDC2, and PRIMA1 in plasma samples

Aberrant methylation is one of the most frequent epigenetic alterations that can contribute to tumor formation. Cell-free DNA can originate from tumor tissue; therefore, the evaluation of methylation markers in cell-free DNA can be a promising method for cancer screening. Our aim was to develop a panel of biomarkers with altered methylation along the colorectal adenoma-carcinoma sequence in both colonic tissue and plasma. Methylation of selected CpG sites in healthy colonic (n = 15), adenoma (n = 15), and colorectal cancer (n = 15) tissues was analyzed by pyrosequencing. MethyLight PCR was applied to study the DNA methylation of SFRP1, SFRP2, SDC2, and PRIMA1 gene promoters in 121 plasma and 32 biopsy samples. The effect of altered promoter methylation on protein expression was examined by immunohistochemistry. Significantly higher (P < 0.05) DNA methylation levels were detected in the promoter regions of all 4 markers, both in CRC and adenoma tissues compared with healthy controls. Methylation of SFRP1, SFRP2, SDC2, and PRIMA1 promoter sequences was observed in 85.1%, 72.3%, 89.4%, and 80.9% of plasma samples from patients with CRC and 89.2%, 83.8%, 81.1% and 70.3% from adenoma patients, respectively. When applied as a panel, CRC patients could be distinguished from controls with 91.5% sensitivity and 97.3% specificity [area under the curve (AUC) = 0.978], while adenoma samples could be differentiated with 89.2% sensitivity and 86.5% specificity (AUC = 0.937). Immunohistochemical analysis indicated decreasing protein levels of all 4 markers along the colorectal adenoma-carcinoma sequence. Our findings suggest that this methylation biomarker panel allows non-invasive detection of colorectal adenoma and cancer from plasma samples.

Risk factors for metachronous adenoma in the residual colon of patients undergoing curative surgery for colorectal cancer

PURPOSE

Adenoma detection in colorectal cancer survivors is poorly characterised with insufficient evidence to inform frequency of surveillance schedule. The aim of this study was to examine adenoma incidence and recurrence in patients who have undergone colorectal cancer resection with curative intent. Survival outcomes were compared to determine if the presence of adenomas could be used to identify patients at higher risk of local recurrence.

METHODS

This is a retrospective observational cohort study at a single tertiary institution between 2006 and 2012. Five hundred fifteen consecutive patients with stage I-III colorectal cancer who had preoperative colonoscopy and curative surgery were included (median follow-up 56 months (36-75 months).

RESULTS

In total, 352/515 (68%) patients underwent postoperative surveillance colonoscopy in the first 5 years after resection. Male gender was associated with greater risk of detecting synchronous adenoma at index colonoscopy or in the resection specimen (OR 2.35, p < 0.001). In the first 5 years after cancer surgery, synchronous adenoma, male gender and right sided primary tumour were independent predictors of metachronous lesions (OR 2.13, p = 0.009; OR 2.07, p = 0.027 and OR 2.34, p = 0.004, respectively). Presence of synchronous or metachronous adenoma had no impact upon incidence of local recurrence, overall or disease free survival.

CONCLUSIONS

Patients with synchronous adenoma remain at high risk of adenoma recurrence despite undergoing colonic resection and should be considered for early endoscopic surveillance. Men and those undergoing right-sided resection have a higher risk of metachronous adenoma in the long term and may benefit from more frequent endoscopic surveillance post resection.

Recent insights into nanotechnology development for detection and treatment of colorectal cancer

The global incidence of colorectal cancer (CRC) is 1.3 million cases. It is the third most frequent cancer in males and females. Most CRCs are adenocarcinomas and often begin as a polyp on the inner wall of the rectum or colon. Some of these polyps become malignant, eventually. Detecting and removing these polyps in time can prevent CRC. Therefore, early diagnosis of CRC is advantageous for preventive and instant action interventions to decrease the mortality rates. Nanotechnology has been enhancing different methods for the detection and treatment of CRCs, and the research has provided hope within the scientific community for the development of new therapeutic strategies. This review presents the recent development of nanotechnology for the detection and treatment of CRC.