Cancer risk and genotype-phenotype correlation in Japanese patients with Cowden syndrome.

BACKGROUND: Cowden syndrome (CS) is an autosomal-dominant hereditary disorder caused by a germline PTEN variant and characterized by multiple hamartomas and a high risk of cancers. However, no detailed data on CS in Asian patients nor genotype-phenotype correlation have been reported. METHODS: We performed the first Japanese nationwide questionnaire survey on CS and obtained questionnaire response data on 49 CS patients. RESULTS: Patients included 26 females (median age 48 years). The incidence of breast, thyroid, endometrium, and colorectal cancer was 32.7%, 12.2%, 19.2% (among females), and 6.1%, respectively. The incidence of any cancers was relatively high among all patients (46.9%, 23/49), and particularly female patients (73.1%, 19/26), compared with previous reports from Western countries. Gastrointestinal (GI) polyps were more frequently found throughout the GI tract compared with previous studies. PTEN variants were detected in 95.6% (22/23) of patients; 12 in the N-terminal region (11 in phosphatase domain) and 10 in the C-terminal (C2 domain) region. The incidence of cancer in the C2 domain group was significantly higher than in the N-terminal region (phosphatase) group. All female patients with C2 domain variant had breast cancer. CONCLUSION: Our data suggest that Japanese patients with CS, particularly female patients and patients with C2 domain variant may have a high risk of cancers.

[Clinical features of 60 patients with ischemic colitis].

Clinical features of 60 patients with ischemic colitis diagnosed at our hospital were analyzed. Ischemic colitis developed in 58 patients (97%) shortly after the evening meal, and in 52 patients (87%), it occurred while the patients were asleep from night to daybreak. The supine position while sleeping resulted in a decrease in the blood flow to the colonic wall and an increase in the intraluminal pressure due to a delay in excretion of the contents of the gut. In addition, increased peristalsis and intraluminal pressure after the evening meal triggered ischemic colitis. Ischemic colitis in the young adult group (<40 years) was more frequently mild because they did not experience arteriosclerosis-related diseases and constipation, and these intestinal factors were considered to contribute to the onset of the disease. In the elderly group (≥70 years), ischemic colitis was more severe than that in the young adult group because ischemic colitis in the elderly group was caused by both vascular and intestinal factors. The severity score evaluated by endoscopic findings revealed a marked correlation with age, clinical symptoms, leukocyte count, and CRP value. The final linear regression model determined leukocyte count, age, and digestive symptoms as substantial independent predictors. In several cases in our study, ischemic colitis occurred more often when exposed to a high percentage of humidity;thus, we speculated that high humidity played an essential role in the pathogenesis of ischemic colitis.

Bleeding Risk Related to Upper Gastrointestinal Endoscopic Biopsy in Patients Receiving Antithrombotic Therapy: A Multicenter Prospective Observational Study.

BACKGROUND: Although antithrombotic agents are widely used for cardiac and cerebrovascular disease prevention, they increase the risk of gastrointestinal (GI) bleeding. OBJECTIVE: To examine GI bleeding risk in association with an esophagogastroduodenoscopy (EGD) biopsy performed in patients without cessation of antithrombotic therapy. METHODS: This study was prospectively conducted at 14 centers. EGD biopsies were performed in patients receiving antithrombotic agents without cessation, as well as age- and sex-matched controls not receiving antithrombotic therapy. Patients treated with warfarin before the biopsy had a prothrombin time-international normalized ratio level <3.0. The proportion of GI bleeding events was compared between the groups. RESULTS: The patient group (n = 277) underwent a total of 560 biopsies while continuing antithrombotic therapy, of whom 24 were receiving multiple antiplatelet drugs, and 9 were receiving both antiplatelet and anticoagulant agents. The control patients (n = 263) underwent 557 biopsies. The upper-GI bleeding rate within 30 days after the EGD biopsy did not increase in patients without cessation of antithrombotic treatment, regardless of receiving single or multiple antithrombotic agents. CONCLUSIONS: We found no significant increase in upper-GI bleeding risk following an EGD biopsy in patients taking antithrombotic agents, suggesting its safety without the need for antithrombotic treatment interruption.

[A refractory case of ulcerative colitis developed after the cessation smoking achieved clinical and endoscopic remission after resuming smoking].

A 42-year-old man, who had stopped smoking almost one year ago, visited our hospital for hematochezia. He was diagnosed as having ulcerative colitis and was prescribed 5-amino salicylic acid and corticosteroids, which led to the remission of his disease. However, the disease relapsed after sufficient continuous corticosteroids administration and persisted despite 5-amino salicylic acid administration and intensive treatment with corticosteroids, immune modulators, leukocyte apheresis, and anti-TNF-α antibodies. Curiously, clinical remission was achieved after he resumed smoking, and colonoscopy revealed mucosal healing. Such remission may be attributable to anti-inflammatory effects of smoking nicotine and carbon oxides.

Effect of pancreatic juice cytology and/or endoscopic ultrasound-guided fine-needle aspiration biopsy for pancreatic tumor.

BACKGROUND AND AIM: Endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNA) can now provide a cytopathological diagnosis of pancreatic malignancy with higher success rates. However, EUS-FNA cannot be carried out for lesions of minimally invasive carcinoma because they cannot be detected by endoscopic ultrasonography, and in cases of intraductal papillary mucinous carcinoma (IPMC) because of the potential for needle tract seeding. A recent study has shown that pancreatic juice cytology (PJC) is useful for diagnosing pancreatic cancer. This study's aim was to evaluate whether PJC strengthens the diagnostic power of EUS-FNA for pancreatic masses. METHODS: A total of 161 patients, who were suspected to have a pancreatic mass on conventional ultrasound and/or computed tomography, was enrolled. RESULTS: EUS-FNA was carried out in 121 cases, and PJC was performed in 83 cases. An adequate specimen was obtained for EUS-FNA in 96.0% and for PJC in 98.9%. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 86.0%, 100%, 100%, 70.5%, and 89.5% for EUS-FNA, and 71.4%, 100%, 100%, 84.4%, and 88.8% for PJC, respectively. EUS-FNA and/or PJC for the diagnosis of pancreatic tumor had a sensitivity of 92.5%, specificity of 100%, positive predictive value of 100%, negative predictive value of 91.7%, and accuracy of 95.9%. The diagnostic accuracy of EUS-FNA and/or PJC was significantly higher than that of EUS-FNA alone or PJC alone. CONCLUSION: PJC improved the diagnostic utility of EUS-FNA for pancreatic tumor.

Autophagy-Related Gene ATG7 Polymorphism Could Potentially Serve as a Biomarker of the Progression of Atrophic Gastritis.

Cytotoxin-associated gene A (CagA) is an oncoprotein that H. pylori injects into the host's gastric epithelial cells and that induces proinflammatory cytokines, such as interleukin (IL)-18 and IL-1ß. As a result, it leads to atrophic gastritis (AG), a precancerous lesion of gastric cancer. On the other hand, host cells degrade CagA using autophagy systems. However, few studies exist about the single nucleotide polymorphisms (SNPs) in MAP1LC3A, MAP1LC3B, ATG4A, ATG4B, ATG4C, ATG7, and ATG13, which belong to the autophagy-related genes concerning AG. This study aimed to detect biomarkers associated with AG. Herein, H. pylori-positive subjects (n = 200) were divided into the AG (n = 94) and non-AG (n = 106) groups. Thirty tag SNPs were selected from the above seven candidate genes. The SNP frequency between the two groups was analyzed. The frequency of the C/T or T/T genotype at rs4683787 of ATG7 was significantly lower in the AG group than in the non-AG group (p = 0.034, odds ratio = 0.535). Based on multivariate analysis, the C/C genotype of rs4684787 and age were independently associated with gastric mucosal atrophy. This finding helps stratify the patients needing timely endoscopic screening or early eradication of H. pylori.

Partial Stent-in-Stent Method with an Uncovered Self-Expandable Metallic Stent for Unresectable Malignant Hilar Bile Duct Obstruction.

(1) Background: There is controversy regarding stent placement for unresectable malignant hilar biliary obstruction (UMHBO). We mainly use the partial stent-in-stent (PSIS) method with an uncovered self-expandable metallic stent (UCSEMS) based on the drainage area and patency period. In this study, we investigated the usefulness and safety of the PSIS method. (2) Methods: In total, 59 patients who underwent the PSIS method for UMHBO at our hospital were included in the study. The technical success rate, clinical success rate, time to recurrent biliary obstruction (TRBO) and overall survival (OS) from the first placement, factors affecting TRBO and OS, and early complications within 30 days after the procedure were evaluated retrospectively. (3) Results: The technical and clinical success rates were 100% and 96.6%, respectively, with a TRBO of 121 days [95% confidence interval: 82-231] and an OS of 194 days [95% confidence interval: 113-305] after the first placement. Early complications occurred in nine patients (15.3%), including five cases of cholangitis, three cases of pancreatitis, and one case of cholecystitis. (4) Conclusions: The PSIS method for UMHBO is safe and useful with high technical and clinical success rates.

Serum Activin A Is a Novel Biomarker of Endoscopic Activity in Ulcerative Colitis.

Background: Endoscopic healing (EH) is the long-term therapeutic goal for ulcerative colitis (UC). Since repeated colonoscopies are inconvenient and invasive, a surrogate biomarker for endoscopic activity is needed. Activin A is one of the transforming growth factor-ß superfamily of proteins and has been shown to be associated with intestinal inflammation. Methods: This single-center observational study included 27 Japanese patients with UC in clinical remission who underwent colonoscopy and blood sampling. We investigated the correlations between laboratory parameters, including serum activin A levels, and endoscopic activity, classified by the Mayo endoscopic subscore (MES) in these patients. Results: This study included 15 males and 12 females. The median age was 44.0 years. In terms of endoscopic activity, five patients were diagnosed with MES 0, 14 patients with MES 1, seven patients with MES 2, and one patient with MES 3. The median serum activin level was 134.8 pg/mL (interquartile range (IQR), 105.3 - 188.1). Serum activin A levels were significantly correlated with the MES (Spearman's rank correlation coefficient r = 0.591, P = 0.001), which was better than that of C-reactive protein (CRP) (r = 0.487, P = 0.010). In the comparison between the EH group (MES 0) and non-EH group (MES 1-3), patients without EH had significantly higher serum activin A levels (Mann-Whitney U test, P = 0.047). A cutoff value of 133.6 pg/mL indicated non-EH with a sensitivity and specificity of 0.682 and 1.000, respectively. The area under the curve (AUC) of serum activin A for detecting non-EH was 0.791 (95% confidence interval (CI), 0.618 - 0.964), while that of CRP was 0.723 (95% CI, 0.504 - 0.941). Conclusions: The serum activin A level is a potential novel biomarker of endoscopic activity in UC.

Current status and future perspective of linked color imaging for gastric cancer screening: a literature review.

Screening endoscopy has advanced to facilitate improvements in the detection and prognosis of gastric cancer. However, most early gastric cancers (EGCs) have subtle morphological or color features that are difficult to detect by white-light imaging (WLI); thus, even well-trained endoscopists can miss EGC when using this conventional endoscopic approach. This review summarizes the current and future status of linked color imaging (LCI), a new image-enhancing endoscopy (IEE) method, for gastric screening. LCI has been shown to produce bright images even at a distant view and provide excellent visibility of gastric cancer due to high color contrast relative to the surrounding tissue. LCI delineates EGC as orange-red and intestinal metaplasia as purple, regardless of a history of Helicobacter pylori (Hp) eradication, and contributes to the detection of superficial EGC. Moreover, LCI assists in the determination of Hp infection status, which is closely related to the risk of developing gastric cancer. Transnasal endoscopy (ultra-thin) using LCI is also useful for identifying gastric neoplastic lesions. Recently, several prospective studies have demonstrated that LCI has a higher detection ratio for gastric cancer than WLI. We believe that LCI should be used in routine upper gastrointestinal endoscopies.

Rheumatoid Arthritis Symptoms Diagnosed by Rheumatic Immune-related Adverse Events Caused by Nivolumab in a Patient with Esophageal Cancer.

This report described the case of a 70-year-old man who developed polyarthralgia after nivolumab treatment for recurrent esophageal cancer. Arthritis developed after initiating nivolumab therapy, and the patient tested positive for rheumatoid factor and anti-citrullinated peptide antibodies. The hand and elbow joints were already deformed, suggesting that he had had rheumatoid arthritis for several years and that the symptoms had only become apparent after nivolumab administration. This patient had rheumatoid arthritis, which was diagnosed as a nivolumab-induced rheumatic immune-related adverse event (rh-irAEs). Arthralgia during nivolumab administration can occur in rh-irAE cases. Patients should be assessed for autoimmune diseases before initiating immune checkpoint inhibitors.

Comparative study between histochemical mucus volume, histopathological findings, and endocytoscopic scores in patients with ulcerative colitis.

Ulcerative colitis (UC) causes a reduction in goblet cells. However, there have been few reports on the relationship between endoscopic and pathological findings and mucus volume. In this study, we quantitatively evaluated histochemical colonic mucus volume by fixing biopsied tissue sections taken from patients with UC in Carnoy's solution and compared it with endoscopic and pathological findings to determine whether there is a correlation between them. Observational study. A single-center, university hospital in Japan. Twenty-seven patients with UC (male/female, 16/11; mean age, 48.4 years; disease median duration, 9 years) were included in the study. The colonic mucosa of the most inflamed area and the surrounding less inflamed area were evaluated separately by local MES and endocytoscopic (EC) classification. Two biopsies were taken from each area; one was fixed with formalin for histopathological evaluation, and the other was fixed with Carnoy's solution for the quantitative evaluation of mucus via histochemical Periodic Acid Schiff and Alcian Blue staining. The relative mucus volume was significantly reduced in the local MES 1-3 groups, with worsening findings in EC-A/B/C and in groups with severe mucosal inflammation, crypt abscess, and severe reduction in goblet cells. The severity of inflammatory findings in UC by EC classification correlated with the relative mucus volume suggesting functional mucosal healing. We found a correlation between the colonic mucus volume and endoscopic and histopathological findings in patients with UC, and a stepwise correlation with disease severity, particularly in EC classification.

Helicobacter pylori-negative Gastric Adenocarcinoma Mimicking Verrucous Gastritis in the Antrum: A Case Report and Literature Review.

A 46-year-old man was referred to our hospital for the examination of a flat elevated lesion with an erosion-like depression, located on the greater curvature of the antrum. Endoscopic submucosal dissection was performed. Histological findings of the resected specimen demonstrated a well-differentiated tubular adenocarcinoma with a diameter of 12 mm. No atrophy was observed in the tumor-adjacent mucosa. Serum Helicobacter pylori antibody estimation and 13C-urea breath tests yielded negative results. Immunohistochemical staining was positive for both gastric mucin and intestinal mucin. The final diagnosis was well-differentiated tubular adenocarcinoma with a gastrointestinal phenotype that originated in mucosa uninfected by H. pylori.

Polymorphism in autophagy-related genes LRP1 and CAPZA1 may promote gastric mucosal atrophy.

BACKGROUND: Helicobacter pylori secretes cytotoxin-associated gene A (CagA) into the gastric epithelium, causing gastric mucosal atrophy (GMA) and gastric cancer. In contrast, host cells degrade CagA via autophagy. However, the association between polymorphisms in autophagy-related genes and GMA must be fully elucidated. RESULTS: We evaluated the association between single nucleotide polymorphisms (SNPs) in autophagy-related genes (low-density lipoprotein receptor-related protein 1, LRP1; capping actin protein of muscle Z-line alpha subunit 1, CAPAZ1; and lysosomal-associated membrane protein 1, LAMP1) and GMA in 200 H. pylori-positive individuals. The frequency of the T/T genotype at rs1800137 in LRP1 was significantly lower in the GMA group than in the non-GMA group (p = 0.018, odds ratio [OR] = 0.188). The frequencies of the G/A or A/A genotype at rs4423118 and T/A or A/A genotype at rs58618380 of CAPAZ1 in the GMA group were significantly higher than those in the non-GMA group (p = 0.029 and p = 0.027, respectively). Multivariate analysis revealed that C/C or C/T genotype at rs1800137, T/A or A/A genotype at rs58618380, and age were independent risk factors for GMA (p = 0.038, p = 0.023, and p = 0.006, respectively). Furthermore, individuals with the rs1800137 C/C or C/T genotype of LRP1 had a 5.3-fold higher susceptibility to GMA. These genetic tests may provide future directions for precision medicine for individuals more likely to develop GMA. CONCLUSION: LRP1 and CAPZA1 polymorphisms may be associated with the development of GMA.

ATG16L1 and ATG12 Gene Polymorphisms Are Involved in the Progression of Atrophic Gastritis.

Helicobacter pylori (H. pylori) infection causes a progression to atrophic gastritis and results in gastric cancer. Cytotoxin-associated gene A (CagA), a major virulence factor of H. pylori, is injected into gastric epithelial cells using the type IV secretion system. On the other hand, gastric epithelial cells degrade CagA using an autophagy system, which is strictly regulated by the autophagy-related (ATG) genes. This study aimed to identify SNPs in ATG5, ATG10, ATG12, and ATG16L1 associated with gastric mucosal atrophy (GMA). Here, two-hundred H. pylori-positive participants without gastric cancer were included. The degree of GMA was evaluated via the pepsinogen method. Twenty-five SNPs located in the four candidate genes were selected as tag SNPs. The frequency of each SNP between the GMA and the non-GMA group was evaluated. The rs6431655, rs6431659, and rs4663136 in ATG16L1 and rs26537 in ATG12 were independently associated with GMA. Of these four SNPs, the G/G genotype of rs6431659 in ATG16L1 has the highest odd ratio (Odds ratio = 3.835, 95% confidence intervals = 1.337-1.005, p = 0.008). Further functional analyses and prospective analyses with a larger sample size are required.

Predictive Factors for Efficacy of Oral Tacrolimus Induction Therapy in Moderate to Severe Ulcerative Colitis Patients: Large Multicenter Retrospective Cohort Study.

BACKGROUND: Tacrolimus (TAC), a calcineurin inhibitor, is used for remission induction therapy in patients with moderate to severe ulcerative colitis (UC), with short-term efficacy and related predictive factors shown in previous cohort studies. However, most studies reported data for only a limited number of patients enrolled from a single center. We performed a large multicenter retrospective cohort study to identify factors related to prediction of clinical remission in UC patients treated with oral TAC. METHODS: The medical records of patients with moderate to severe UC treated with oral TAC as induction therapy at 7 institutions between April 2009 and March 2017 were retrospectively reviewed. RESULTS: A total of 216 patients who received TAC for induction were analyzed, of whom 123 (56.9%) showed clinical remission at week 12. Logistic regression analysis indicated that previous or current use of antitumor necrosis factor (TNF)-α antibodies (odds ratio [OR], 0.259; P = .006), and concomitant treatment with 5-aminosalicylate (5-ASA) at the baseline (OR, 0.268; P = .005) were independent predictive factors correlated with failure of clinical remission, whereas higher levels of C-reactive protein (OR, 1.124; P = .014) predicted achievement of clinical remission. CONCLUSIONS: Results of this multicenter study clearly indicate the efficacy of TAC induction therapy for patients with moderate to severe UC. Notably, previous or current use of anti-TNF-α antibodies was associated with poor achievement of clinical remission by week 12.

Fhit, E-cadherin, p53, and activation-induced cytidine deaminase expression in endoscopically resected early stage esophageal squamous neoplasia.

BACKGROUND AND AIM: Abnormal expression of Fragile Histidine Triad (Fhit), E-cadherin and p53 is observed in esophageal squamous cell carcinoma. It has recently been reported that aberrant expression of activation-induced cytidine deaminase (AID) in gastric epithelium leads to the accumulation of nucleotide alterations in the p53 gene. However, little is known about the association between these molecular events and the clinicopathological characteristics of early stage esophageal squamous neoplasia, especially in endoscopically resected tumors. METHODS: Esophageal squamous neoplasias (n = 49) comprising nine cases of low-grade intraepithelial neoplasia (LGIN), 22 of high-grade intraepithelial neoplasia/carcinoma in situ (HGIN/CIS) and 18 of invasive cancers, were endoscopically resected. Their expression of the tumor-related proteins: Fhit, E-cadherin, p53 and AID was assessed using immunohistochemical methods, and the relationship between protein expression and clinicopathological data was examined. RESULTS: Reduced or absent Fhit and E-cadherin expression was detected in 22% and 0% of LGIN cases, 73% and 14% of HGIN/CIS cases, and 94% and 61% of invasive cancer cases, respectively, showing progressive increases during neoplastic progression (Fhit: P < 0.01, E-cadherin: P < 0.01). Although p53 and AID were overexpressed in these samples, no change in their expression occurred during neoplastic progression. Moreover, p53 expression was not significantly associated with AID expression. CONCLUSIONS: These results indicate that a decrease in Fhit and E-cadherin expression could be related to the development and progression of esophageal squamous neoplasia, and that the expression of p53 was independent of aberrant AID expression in the early stage of esophageal carcinogenesis.

Gastric Cancer Screening in Japan: A Narrative Review.

Gastric cancer is the second leading cause of cancer incidence in Japan, although gastric cancer mortality has decreased over the past few decades. This decrease is attributed to a decline in the prevalence of H. pylori infection. Radiographic examination has long been performed as the only method of gastric screening with evidence of reduction in mortality in the past. The revised 2014 Japanese Guidelines for Gastric Cancer Screening approved gastric endoscopy for use in population-based screening, together with radiography. While endoscopic gastric cancer screening has begun, there are some problems associated with its implementation, including endoscopic capacity, equal access, and cost-effectiveness. As H. pylori infection and atrophic gastritis are well-known risk factors for gastric cancer, a different screening method might be considered, depending on its association with the individual's background and gastric cancer risk. In this review, we summarize the current status and problems of gastric cancer screening in Japan. We also introduce and discuss the results of gastric cancer screening using H. pylori infection status in Hoki-cho, Tottori prefecture. Further, we review risk stratification as a system for improving gastric cancer screening in the future.

The First Case of Gastric Neuroendocrine Tumors Induced by a Proton Pump Inhibitor in von Hippel-Lindau Disease.

Von Hippel-Lindau (VHL) disease is a rare inherited familial syndrome complicated with various neoplasms, including neuroendocrine tumors (NETs). We herein report the first case of multiple gastric NETs in a 45-year-old man with VHL. He had multiple gastric polyps, and several endoscopic resected lesions were diagnosed as NETs. The serum gastrin level was elevated because he was taking a proton pump inhibitor (PPI). We suspected that gastrin had played a role in the development of NETs, and the remaining polyps were followed up with discontinuation of the PPI. The NETs gradually reduced in size until they became hard to notice on endoscopy and have remained nearly invisible for over eight years.

Pyloric Incompetence Associated with Helicobactor pylori Infection and Correlated to the Severity of Atrophic Gastritis.

Duodenogastric reflux (DGR) causes bile reflux gastritis (BRG) and may develop into gastric cancer. DGR is classified as primary in non-operated stomachs or secondary to surgical intervention. Primary DGR and Helicobacter pylori (H. pylori) infection are reportedly related. However, the mechanism is not fully understood. This study aimed to elucidate the relationship between H. pylori infection and pyloric incompetence in a non-operated stomach. A total of 502 non-operated participants who underwent an upper intestinal endoscopy were prospectively enrolled. Endoscopic findings (EAC, endoscopic atrophy classification; nodular gastritis; xanthoma; fundic gland polyp; and incompetence of pylorus), sex, age, gastrin, pepsinogen (PG) I and PG II levels were evaluated. PG I/PG II ratio, anti-H. pylori-Ab positivity, and atrophic gastritis status were significantly different between the normal and incompetent pylori (p = 0.043, <0.001, and 0.001, respectively). Open-type atrophic gastritis was significantly higher in the incompetent pylori. Incompetence of the pylorus and EAC were moderately correlated (Cramer's V = 0.25). Multivariate analysis revealed that the presence of anti-H. pylori-Ab was the only independent factor associated with the incompetence of the pylorus, with an adjusted odds ratio of 2.70 (95% CI: 1.47−4.94, p = 0.001). In conclusion, pyloric incompetence was associated with H. pylori infection and moderately correlated to the severity of atrophic gastritis in non-operated stomachs.

Objective Methods of 5-Aminolevulinic Acid-Based Endoscopic Photodynamic Diagnosis Using Artificial Intelligence for Identification of Gastric Tumors.

Positive diagnoses of gastric tumors from photodynamic diagnosis (PDD) images after the administration of 5-aminolevulinic acid are subjectively identified by expert endoscopists. Objective methods of tumor identification are needed to reduce potential misidentifications. We developed two methods to identify gastric tumors from PDD images. Method one was applied to segmented regions in the PDD endoscopic image to determine the region in LAB color space to be attributed to tumors using a multi-layer neural network. Method two aimed to diagnose tumors and determine regions in the PDD endoscopic image attributed to tumors using the convoluted neural network method. The efficiencies of diagnosing tumors were 77.8% (7/9) and 93.3% (14/15) for method one and method two, respectively. The efficiencies of determining tumor region defined as the ratio of the area were 35.7% (0.0-78.0) and 48.5% (3.0-89.1) for method one and method two, respectively. False-positive rates defined as the ratio of the area were 0.3% (0.0-2.0) and 3.8% (0.0-17.4) for method one and method two, respectively. Objective methods of determining tumor region in 5-aminolevulinic acid-based endoscopic PDD were developed by identifying regions in LAB color space attributed to tumors or by applying a method of convoluted neural network.