Value of Virtual Colonoscopy with 64 Row CT in Evaluation of Colorectal Cancer

Advances in tests for colorectal cancer screening and diagnosis

INTRODUCTION

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths globally. Nonetheless, with early detection of CRC or its precancerous lesions, mortality, and CRC incidence can be reduced. Although colonoscopy is currently the gold standard for CRC screening and diagnosis, its invasive nature, and troublesome bowel preparation deter patient participation. Therefore, there is a need to expand the use of noninvasive or minimally invasive methods to increase patient compliance.

AREAS COVERED

This review summarizes advances in different methods for CRC screening, including stool bacterial and metagenomic markers, fecal proteins, genetic and epigenetic markers in blood and stools, and imaging modalities. The cost-effectiveness of these methods is also discussed. FIT is more cost-effective compared to virtual colonoscopy, mSEPT9 test, and Multitarget Stool DNA test, while the cost-effectiveness of other noninvasive methods requires further evaluation.

EXPERT OPINION

Recent evidence has well demonstrated the usefulness of gut microbiome and certain fecal bacterial markers in the noninvasive diagnosis of CRC and its precancerous lesions. Many of the fecal biomarkers, from host cells or the gut environment, show better diagnostic sensitivity than FIT. New screening tests based on these fecal biomarkers can be expected to replace FIT with higher cost-effectiveness in the near future.

Adapting a 2-week-wait colorectal service in the pandemic using the quantitative faecal immunochemical test

The coronavirus pandemic has brought about an economic and healthcare crisis. This has resulted in delays in virtually all areas of patient care and has forced clinicians to review and adapt their processes, in order to ensure patients continue to have access to timely and effective services. In the author's local Trust, this manifested in altered protocols, developed in order to maintain patient and staff safety while conducting invasive and potentially virus-spreading investigations. A new (temporary) standard operating procedure was developed in conjunction with Cancer Alliance South West to introduce the quantitative faecal immunochemical test (qFIT) as an indicator for diagnostic testing after the majority of diagnostic services were suspended or drastically reduced. Patients would then have their investigation(s) deferred on the basis of a negative result (<10 mcg Hb/g). This cohort (n=120) were revisited once diagnostic services were resumed and referred for CT examination. Audits carried out on the data showed that nine cancers had been identified in the negative qFIT population (lung, prostate, breast, bladder, small bowel carcinoid, oesophageal and three occurrences of caecal carcinoma. This article provides an overview of the experiences and outcomes of a colorectal 2-week-wait service in response to this global pandemic and how this experience will shape the service in the future.

Photodynamic diagnosis and photodynamic therapy of colorectal cancer in vitro and in vivo

This review highlights the various photo diagnostic and treatment methods utilized for CRC, over the last seven years.

Preoperative Serum MicroRNA-155 Expression Independently Predicts Postoperative Cognitive Dysfunction After Laparoscopic Surgery for Colon Cancer

Background

The aim of this study was to examine the association between serum expression of miRNA-155 and postoperative cognitive dysfunction (POCD) after laparoscopic surgery for colon cancer.

Material/Methods

We enrolled 110 patients scheduled to undergo colon tumor resection via laparotomy in Ningbo No. 2 Hospital from July 2013 to November 2015. The blood samples were collected from the participants 1 day before surgery. Multiple logistic regression analysis was used for the analysis of independent predictive biomarkers for POCD.

Results

On the 7^th postoperative day, 29 of the 110 participants developed POCD, yielding a POCD incidence of 26.4%. Age, MMSE score, duration of surgery and anesthesia, serum levels of CRP, TNF-α, urea, creatinine, and miRNA-155 were highly associated with the occurrence of POCD. Serum expression of miRNA-155 was shown by multiple logistic regression analysis to be an independent predictive indicator for POCD after surgery (OR: 2.732; 95%CI 1.415–5.233; P=0.002).

Conclusions

The serum expression of miRNA-155 is an independent predictive factor for POCD after laparoscopic surgery for colon cancer.

Diagnostic value of computed tomography colonography (CTC) after incomplete optical colonoscopy

INTRODUCTION

This study evaluated the role of computed tomography colonography (CTC) in patients who previously underwent incomplete optical colonoscopy (OC). We analyzed the impact of colonic lesions in intestinal segments not studied by OC and extracolonic findings in these patients.

METHODS

Between January 2014 and May 2015, 61 patients with a history of abdominal pain and incomplete OC examination were studied by CTC. CTCs were performed by 320-row CT scan in both the supine and the prone position, without intravenous administration of contrast medium. In all patients both colonic findings and extracolonic findings were evaluated.

RESULTS

Among the study group, 24 CTC examinations were negative for both colonic and extracolonic findings while 6 examinations revealed the presence of both colonic and extracolonic findings. In 24 patients CTC depicted colonic anomalies without extracolonic ones, while in 7 patients it showed extracolonic findings without colonic ones.

DISCUSSION

CTC is a noninvasive imaging technique with the advantages of high diagnostic performance, rapid data acquisition, minimal patient discomfort, lack of need for sedation, and virtually no recovery time. CTC accurately allows the evaluation of the nonvisualized part of the colon after incomplete OC and has the distinct advantage to detect clinically important extracolonic findings in patients with incomplete OC potentially explaining the patient's symptoms and conditioning their therapeutic management.

CONCLUSION

CTC accurately allows the assessment of both colonic and extracolonic pathologies representing a useful diagnostic tool in patients for whom complete OC is not achievable.