Gastrointestinal Endoscopy for Patients with High Levels of Serum CEA and CA19-9

Serum levels of tumor markers, such as carcinoembryonic antigen （CEA） and carbohydrate antigen 19-9 （CA19-9）, are often measured to detect potential malignancy. When these levels are high, the presence or absence of malignancy is confirmed via a more detailed examination using gastrointestinal （GI） endoscopy and computed tomography. The rate of confirmation of malignancy upon such a follow-up is unknown. This study aimed to investigate the malignancy detection rate via GI endoscopy for patients with high levels of serum CEA and CA19-9. All patients who underwent such GI endoscopy between January 2018 and February 2019 at Showa University Hospital were included in this study. The patients were divided into a follow-up group and a screening group, depending on the purpose of measuring their serum CEA/CA19-9 levels. There were 156 patients who underwent GI endoscopy because of high CEA/CA19-9 levels within the study period. Advanced malignant lesions were detected in 10 patients （6.4％）, including seven cases of colorectal cancer and three cases of upper GI malignancies. In the screening group, six cases （5.7％） of GI malignancies were detected, none of which were found in asymptomatic patients without anemia. In the follow-up group, four cases （7.8％） of GI malignancies were detected; three patients were asymptomatic, and one patient had anemia. Our findings suggest that high serum CEA/CA19-9 levels in asymptomatic patients without anemia and without a history of malignancy do not indicate the presence of malignancy. However, high serum CEA/CA19-9 levels may indicate the potential presence of GI malignancies for patients with a history of malignant tumors, even if they are asymptomatic and do not have anemia

Revitalizing the Japanese Economy by Socializing Risk

The almost continuous stagnation of the Japanese economy for the past two decades has had an adverse impact on Japanese households from at least three perspectives: A decline in the standard of living, an increase in risks and uncertainties relating to livelihood, employment, old age, etc., and an increase in income inequality. The majority of economists and policymakers focus their attention on the increase in income inequality. The research discussed here, however, focuses on the increase in risk and uncertainty among households and individuals. Based on this research, we propose a shift to a policy regime centering on the socialization of risk, which will make possible a transition from a society in which individuals bear excessive risks to one in which risk is shared equitably by society as a whole

Magnifying Colonoscopy Findings for Differential Diagnosis of Sessile Serrated Adenoma/Polyps and Hyperplastic Polyps

Sessile serrated adenoma/polyps (SSA/Ps) are thought to be precursors of colorectal cancers. However, current endoscopic techniques for differentiating SSA/Ps from conventional hyperplastic polyps (HPs) have low diagnostic accuracy. The aim of the present study was to assess the ability of mucosal crypt patterns to distinguish SSA/Ps from HPs. We examined 140 lesions from 93 patients that had been diagnosed histologically as SSA/Ps or HPs at the Showa University Hospital between June 2010 and May 2012. Three experienced colonoscopists reviewed the endoscopic findings of magnifying colonoscopy. Type II open-shape (Type II-O) pit patterns and varicose microvascular vessels (VMVs) were identified according to previously proposed definitions. Although 140 lesions were initially identified for the study, 27 lesions were excluded from analysis because of insufficient endoscopic findings. Thus, endoscopic findings from a total of 113 lesions (68 SSA/Ps and 45 HPs) were evaluated. Of 113 serrated polyps, 51 lesions (44 SSA/Ps and 7 HPs; P<0.01) had Type II-O pit patterns. The inter- and intra-observer agreement for these patterns among three colonoscopists was κ=0.61 (range 0.57–0.65) and κ=0.68 (range 0.52–0.94), respectively. The positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity of Type II-O pit patterns for differentiating between SSA/P and HP were 86%, 61%, 65%, and 84%, respectively. In contrast, the PPV, NPV, sensitivity, and specificity of VMVs were 68%, 43%, 37%, and 73%, respectively. The results indicate that Type II-O mucosal crypt patterns may be useful for the differential diagnosis of SSAPs and HPs

Conditional inference tree models to perceive depth of invasion in T1 colorectal cancer

Background and aim: accurate diagnosis of invasion depth for T1 colorectal cancer is of critical importance as it decides optimal resection technique. Few reports have previously covered the effects of endoscopic morphology on depth assessment. We developed and validated a novel diagnostic algorithm that accurately predicts the depth of early colorectal cancer.Methods: we examined large pathological and endoscopic databases compiled between Jan 2015 and Dec 2018. Training and validation data cohorts were derived and real-world diagnostic performance of two conditional interference tree algorithms (Models 1 and 2) was evaluated against that of the Japan NBI-Expert Team (JNET) classification used by both expert and non-expert endoscopists.Results: model 1 had higher sensitivity in deep submucosal invasion than that of JNET alone in both training (45.1% vs. 28.6%, p &lt; 0.01) and validation sets (52.3% vs. 40.0%, p &lt; 0.01). Model 2 demonstrated higher sensitivity than Model 1 (66.2% vs. 52.3%, p &lt; 0.01) in excluding deeper invasion of suspected Tis/T1a lesions.Conclusion: we discovered that machine-learning classifiers, including JNET and macroscopic features, provide the best non-invasive screen to exclude deeper invasion for suspected Tis/T1 lesions. Adding this algorithm improves depth diagnosis of T1 colorectal lesions for both expert and non-expert endoscopists

Factors associated with endoscopic treatment decisions for T1b or more deeply invading colorectal cancers

Surgical resection for colorectal cancer（CRC）that deeply invades the submucosa（≥1,000µm）（T1b）has been recommended to reduce the potential risk of lymph node metastasis. In clinical settings, cases of pathological T1b exist, and these cases are treated with endoscopic resection（ER）for various reasons. However, factors that influence the choice of ER to treat T1b CRC remain unknown. Therefore, in this study, we investigated the factors associated with the choice of endoscopic treatments in patients diagnosed with pathological T1b or a more deeply invading CRC. To achieve this aim, we conducted a case series investigation of the previously conducted endoscopic diagnoses, after which we selected treatments for colorectal lesions. The case series comprised 83 lesions endoscopically diagnosed as early CRC, which was subsequently reviewed by eight endoscopists with various levels of experience in magnifying colonoscopy at Showa University Hospital. Then, pathological T1b or T2 lesions were extracted from the case series. We also assessed factors related to ER selection for these lesions using multiple logistic regression and analyzed their contributions using decision tree analysis. Eighteen cases with pathological T1b or more deeply invading lesions were extracted, and the analyses were conducted using 144 data obtained from these 18 lesions as interpreted by the eight reviewers. With multivariate logistic regression, a low estimation level for T1b and high confidence to perform ER were identified as independent factors affecting the selection of ER for T1b. The decision tree analysis further indicated that confidence levels to perform ER influenced treatment selection, especially in lesions diagnosed as probable T1b. Our study therefore demonstrated that factors affecting the selection of ER to treat T1b CRCs were low estimations during endoscopic diagnosis and high confidence to conduct the ER procedure

Clinicopathological and Molecular Features of Laterally Spreading Tumors

Colorectal flat-elevated neoplasms can be classified into small-flat adenoma and laterally spreading tumors (LSTs), which can then be sub-categorized into granular-type (LST-G) and nongranular-type (LST-NG) LSTs with possible biological differences between them. We evaluated clinicopathological features and KRAS / BRAF mutations in 24 LST-Gs and 57 LST-NGs. PCR-based pyrosequencing assays were used to determine the presence of activating mutations in codons 12 and 13 of KRAS and in codon 600 of BRAF. Significant differences between LST-Gs and LST-NGs were observed in tumor size (30mm vs. 15mm, P<0.0001) and the frequency of KRAS mutations (75%, 18/24 vs. 5%, 3/57, P< 0.0001). For LST-NGs, the histological grade was increased with an increase in the tumor size. The frequency of submucosal cancer (SM-ca) was also higher in tumors of at least 20mm than in tumors smaller than 20mm (P<0.05). In contrast, there was no indication of a size-dependent increase in the histological grade. No significant difference in the frequency of KRAS mutation in LST-Gs and LST-NGs was related to tumor size. Two subtypes of LSTs were observed to have different clinicopathological and molecular characteristics. These findings suggest that different molecular mechanisms could exist in these subtypes of colorectal flat-type neoplasms

Accuracy of the Differential Diagnosis of Colorectal Serrated Polyps Using a Conventional Endoscope: A Prospective Study

Some serrated polyps （SPs） are thought to be precursors of colorectal cancers. However, the endoscopic diagnosis of sessile serrated adenoma/polyps （SSA/Ps） has been reported to have a low accuracy. The aim of this study was to clarify the ability to distinguish between SSA/Ps and non-SSA/Ps by using mucosal crypt patterns combined with endoscopic findings. In total, 457 consecutive patients who underwent endoscopic resection for colorectal polyps at the Showa University Hospital from April 2007 to December 2010 were prospectively enrolled in this study. Before treatment, mucosal crypt patterns of the lesions were classified into three types （hyperplastic, adenomatous, and mixed pattern）. When the lesion had an adenomatous pattern with a cerebriform appearance or mixed pattern, it was diagnosed as a traditional serrated adenoma （TSA）. If the lesion had a hyperplastic pattern and was sized 6mm or more in the proximal colon or 10mm or more in the distal colon, it was diagnosed as an SSA/P by the endoscopist. We analyzed 1,151 colorectal polyps in this study. Endoscopically, 117 polyps were diagnosed as SSA/Ps or hyperplastic polyps （HPs）, 998 polyps were conventional adenomas, and 36 polyps were TSAs, with diagnostic accuracies of 94.7％, 94.1％, and 97.3％, respectively. Of the 117 polyps diagnosed as SSA/Ps or HPs, 59 lesions met our criteria for SSA/Ps, with a diagnostic accuracy of 70.9％. Our results indicate that the combination of mucosal crypt patterns and endoscopic findings may be useful for differentiating between SPs and non-SPs. However, additional specific endoscopic features of SSA/Ps are still needed