Assessing synchronous ovarian metastasis in gastric cancer patients using a clinical-radiomics nomogram based on baseline abdominal contrast-enhanced CT: a two-center study

BACKGROUND

To build and validate a radiomics nomogram based on preoperative CT scans and clinical data for detecting synchronous ovarian metastasis (SOM) in female gastric cancer (GC) cases.

METHODS

Pathologically confirmed GC cases in 2 cohorts were retrospectively enrolled. All cases had presurgical abdominal contrast-enhanced CT and pelvis contrast-enhanced MRI and pathological examinations for any suspicious ovarian lesions detected by MRI. Cohort 1 cases (n = 101) were included as the training set. Radiomics features were obtained to develop a radscore. A nomogram combining the radscore and clinical factors was built to detect SOM. The bootstrap method was carried out in cohort 1 as internal validation. External validation was carried out in cohort 2 (n = 46). Receiver operating characteristic (ROC) curve analysis, decision curve analysis (DCA) and the confusion matrix were utilized to assess the performances of the radscore, nomogram and subjective evaluation model.

RESULTS

The nomogram, which combined age and the radscore, displayed a higher AUC than the radscore and subjective evaluation (0.910 vs 0.827 vs 0.773) in the training cohort. In the external validation cohort, the nomogram also had a higher AUC than the radscore and subjective evaluation (0.850 vs 0.790 vs 0.675). DCA and the confusion matrix confirmed the nomogram was superior to the radscore in both cohorts.

CONCLUSIONS

This pilot study showed that a nomogram model combining the radscore and clinical characteristics is useful in detecting SOM in female GC cases. It may be applied to improve clinical treatment and is superior to subjective evaluation or the radscore alone.

Adenoma miss rate determined by very shortly repeated colonoscopy: Retrospective analysis of data from a single tertiary medical center in China

Adenoma miss rate (AMR) has been calculated in several tandem colonoscopy studies, but it costs overmuch to carry out a clinical trial.We aimed to put forward AMR by taking advantage of retrospective data, and to judge the comparability between AMRs from prospective and retrospective data.Data of the patients accepting repeated colonoscopies during January to September 2016 was retrospectively collected and analyzed. Information was recorded, including bowel preparation quality of the first colonoscopy, size, location, histology and whether missed within the first colonoscopy of each single adenoma. AMR was compared by different risk factors through χ test and multivariable logistic regression.Around 267 adenomas were detected during 309 pairs of repeated colonoscopies, of which 66 were missed during the first colonoscopies. AMRs of the lesions small in size, nonadvanced in histology, in poor bowel preparation context and located in the proximal colon, were significantly higher than the opposite ones, and old age and male were related to adenoma missing (P < .05). In multivariable logistic regression analysis, adenoma-related factors (diminutive in size, poor bowel preparation and located in ascending colon, transverse colon or sigmoid colon), and patient-related factors (older than 60 years, male and poor bowel preparation) were found to be independently associated with missing adenomas (P < .05).AMR of retrospective data is comparable to that of tandem studies. Several risk factors influence AMR dramatically, which should be paid attention to.

Long-Term Oncological Outcomes of Endoscopic Stenting as a Bridge to Surgery Versus Emergency Surgery for Malignant Colorectal Obstruction: A Comparative Study

AIM

With consideration of the theoretical link between the stent insertion and the increased risk of tumor cells spillaged, which may lead to distant metastases, there is a concern about long-term clinical outcomes after the usage of self-expanding metallic stents (SEMS) as a "bridge to surgery" in the malignant colorectal obstruction (MCO) treatment. This cohort study aimed to compare the long-term oncological outcomes of SEMS as a bridge to surgery (SEMS group) with those of emergency surgery (ES group) for MCO.

METHODS

Twenty-seven patients who underwent semielective curative resection after endoscopic SEMS insertion were included from October 2007 to December 2012 in the SEMS group were compared with 33 patients who underwent emergency curative surgery for MCO during the same period in the ES group. The clinical pathologic characteristics and the overall survival (OS) rate were compared between the two groups.

RESULTS

There were no significant differences in demographics, tumor stage, location, and histology between the SEMS and ES groups. The median OS times were 37 months for the SEMS group and 23 months for the ES group. The proportions of patients who received postoperative adjuvant chemotherapy were comparable (SEMS group versus ES group, 70.4% versus 45.5%; P = .138). There were no significant differences in terms of the long-term oncological outcome between two groups in the 3-year OS rate (55.6% versus 39.4%; P = .2119) and the 5-year OS rate (48.1% versus 36.4%; P = .3570).

CONCLUSIONS

Long-term oncological outcomes of the SEMS group were comparable to those of the ES group.

Correlation between number of polyps detected per colonoscopy and polyp detection rate in average risk Chinese population of colorectal cancer

AIM: To assess the association between the number of polyps detected per colonoscopy (PPC) and polyp detection rate (PDR).

METHODS: A retrospective analysis was performed of the data for patients who underwent screening colonoscopy in the Digestive Endoscopic Center of Changhai Hospital between March 2010 and February 2013. PDR and PPC were calculated by gender, age and endoscopist. Linear regression analysis was applied to study the relationship between PDR and PPC.

RESULTS: A total of 1928 subjects received complete colonoscopies. There were significant linear correlations between PDR and PPC by age in both genders (men: r = 0.96, P = 0.0092; women: r = 0.97, P = 0.0059). There was also a significant linear correlation by endoscopist (r = 0.88, P < 0.05).

CONCLUSION: There is a significant correlation between PDR and PPC. PPC can act as a supplementary index to help distinguish endoscopists who have different colonoscopy skills.

Detection and miss rates of autofluorescence imaging of adenomatous and polypoid lesions during colonoscopy: a systematic review and meta-analysis

BACKGROUND AND STUDY AIMS

Autofluorescence imaging (AFI) is an endoscopic imaging technique used to increase the detection of premalignant gastrointestinal lesions, and it has gradually become popular in recent years. This meta-analysis was performed to examine whether AFI provides greater efficacy in the detection of adenomatous and polypoid lesions and can even prevent the failure to detect a single adenoma or polyp. The aim of the study was to systematically review the efficacy of AFI in increasing detection rates and decreasing miss rates.

METHODS

Pertinent articles were identified through a search of databases up to December 2013 that included patients who had undergone two same-day colonoscopies (AFI and white light endoscopy [WLE]), followed by polypectomy. Fixed and random effects models were used to detect significant differences between AFI and WLE in regard to adenoma detection rate (ADR), polyp detection rate (PDR), adenoma miss rate (AMR), polyp miss rate (PMR), and procedural time.

RESULTS

A total of 1199 patients from six eligible studies met the inclusion criteria. No significant differences were found in ADR (odds ratio [OR] 1.01; 95 % confidence interval [95 %CI] 0.74 - 1.37), PDR (OR 0.86; 95 %CI 0.57 - 1.30), or advanced ADR (OR 1.22; 95 %CI 0.69 - 2.17). The AMR (OR 0.62; 95 %CI 0.44 - 0.86) and PMR (OR 0.64; 95 %CI 0.48 - 0.85) by AFI were significantly lower than those by WLE. The procedural time of AFI was significantly longer than that of WLE (mean 8.00 minutes; 95 %CI 1.59 - 14.41). Subgroup meta-analysis for the other characteristics was not performed because of insufficiency of the primary data.

CONCLUSIONS

AFI decreases AMR and PMR significantly compared with WLE but does not improve ADR or PDR. AMR and PMR may be decreased by using AFI in flat and small lesions or when less experienced endoscopists perform the procedure.

Rate and reasons for colonoscopic cecal intubation failure in an average risk population of colorectal cancer

AIM: To get the knowledge regarding the rate of colonoscopic cecal intubation failure in an average risk population of colorectal cancer and analyze the reasons for failed intubation.

METHODS: A retrospective analysis was performed of the data for patients who underwent colonoscopy at Changhai Hospital from January 2008 to September 2010. Average risk patients were selected according to their indications and divided into either a successful intubation group or a failed intubation group according to whether cecal intubation was achieved. Total cecal intubation rate (CIR) was calculated. The t test and χ² test were used to compare age, gender composition, bowel preparation status and polyp detection rate (PDR) between the two groups.

RESULTS: A total of 10164 subjects received colonoscopy, of which 613 (6.0%) did not complete the colonic examination. Compared with the success group, the failure group had greater mean age, poorer bowel preparation and higher PDR (P < 0.05), although gender composition was similar. The main reasons for intubation failure was stricture due to occupying lesions, followed by poor bowel preparation. A total of 253 (41.27%) cases of infiltrative cancer were found in the failure group.

CONCLUSION: Advanced age, poor bowel preparation and suffering from infiltrative cancer are associated with failed cecal intubation. The detection rate of advanced colorectal cancer is high in the Chinese average risk populations.