Endoscopic diagnosis of Whipple disease in a patient without gastrointestinal symptoms: A case report.

Whipple's disease is a systemic chronic bacterial infection caused by Tropheryma whipplei, a gram-positive bacillus. T. whipplei infection in the small intestine often causes malabsorption and is often accompanied by gastrointestinal symptoms such as diarrhea and abdominal pain. In this report, we describe our experience with a case of Whipple's disease in which the affected patient did not have the typical gastrointestinal symptoms. The patient was an 80-year-old male who presented with complaints of weight loss and lower leg edema due to malabsorption and shortness of breath during exertion. A blood test revealed a decreased albumin level and an elevated C-reactive protein level. Endoscopic images revealed diffuse white villi, the presence of which extended from the duodenum to the upper jejunum. We made a diagnosis of Whipple's disease based on pathological findings associated with the duodenum, electron microscopic findings, and findings of polymerase chain reaction (PCR) tests (performed using mucosal tissue). Clinical symptoms and endoscopic findings improved with antibiotics. Real-time PCR tests were performed for a quantitative evaluation of the effect of treatment. Endoscopy is useful for diagnosing Whipple's disease when there is an absence of gastrointestinal symptoms, and hypoalbuminemia of unknown etiology is observed.

Risk factors for postoperative bleeding and early death in percutaneous endoscopic gastrostomy: A multicenter retrospective study.

BACKGROUND AND AIM: Comprehensive reports on the risk factors for bleeding and early death after percutaneous endoscopic gastrostomy (PEG) are limited. In this multicenter study, we retrospectively investigated the risk factors for bleeding and early death after PEG. METHODS: Patients (n = 1234) who underwent PEG between 2015 and 2020 at Osaka Medical and Pharmaceutical University and its affiliated hospitals (11 institutions in total) were evaluated for postoperative bleeding and early death (within 60 days) after PEG according to patient characteristics, construction method, medical history, medications, preoperative hematological findings, and perioperative adverse events. Multivariate logistic regression was performed to identify independent predictors of bleeding and early death after PEG. RESULTS: The risk factors for bleeding after PEG were PEG tube insertion using the modified introducer method (odds ratio [OR], 4.37; P = 0.0003), low platelet count (OR, 0.99; P = 0.014), antiplatelet therapy (OR, 2.11; P = 0.036), and heparinization (OR, 4.50; P = 0.007). Risk factors for early death were low body mass index (BMI) (OR, 0.89; P = 0.015), low serum albumin levels (OR, 0.50; P = 0.035), and comorbidity of active cancer (OR, 4.03; P < 0.0001). There was no significant association between bleeding and early death after PEG. CONCLUSIONS: We identified several risk factors for bleeding and early death after PEG. Risk factors for bleeding were PEG tube insertion using the modified introducer method, low platelet count, antiplatelet therapy, and heparinization. Risk factors for early death were low BMI, low serum albumin levels, and comorbidity of active cancer.

Safety, efficacy, and maneuverability of a self-propelled capsule endoscope for observation of the human gastrointestinal tract.

Background and study aims We developed a self-propelled capsule endoscope that can be controlled from outside the body with real-time observation. To improve the device, we conducted a clinical trial of total gastrointestinal capsule endoscopy in healthy subjects to ascertain whether our first-generation, self-propelled capsule endoscope was safe and effective for observing the entire human gastrointestinal tract. Patients and methods After adequate gastrointestinal pretreatment, five healthy subjects were instructed to swallow a self-propelling capsule endoscope and the safety of a complete gastrointestinal capsule endoscopy with this device was assessed. We also investigated basic problems associated with complete gastrointestinal capsule endoscopy. Results No adverse effects of the magnetic field were identified in any of the subjects. No mucosal damage was noted in any of the subjects with the use of our first-generation, self-propelling capsule endoscope. We found that it took longer than expected to observe the stomach; the view was compromised by the swallowed saliva. The pylorus was extremely difficult to navigate, and the endoscope's fin sometimes got caught in the folds of the small intestine and colon. Conclusions To resolve the problems associated with the existing self-propelling capsule endoscope, it may be necessary to not only improve the capsule endoscopes, but also to control the environment within the gastrointestinal tract with medications and other means. Our results could guide other researchers in developing capsule endoscopes controllable from outside the body, thus allowing real-time observation.

The Differential Diagnosis of Colorectal Polyps Using Colon Capsule Endoscopy.

Objective Although colorectal polyps (CPs) can be observed with colon capsule endoscopy (CCE), it is difficult to determine the type of polyp using CCE. The objective of this study was to differentiate adenomatous polyps (APs) from hyperplastic polyps (HPs) with CCE. Methods In this single-center retrospective study, an analysis was conducted on the same CPs with both CCE and colonoscopy (CS) and histopathologically diagnosed as AP or HP. The color difference (ΔE) between the polyp surface and the surrounding mucosa was calculated using the CIE1976 L*a*b* color space method on white light (WL), flexible spectral imaging color enhancement (FICE), and blue mode (BM) CP images. We investigated the ability of the ratio of the color differences (ΔE') to differentiate between APs and HPs. Results The size of all 51 polyps (34 APs, 17 HPs) was 7.5±4.6 mm with CCE and 7.3±4.2 mm with CS, and this difference was not significant (p=0.28). The FICEΔE' of APs was 3.3±1.8, which was significantly higher than the FICEΔE' of HPs (1.3±0.6; p<0.001). A receiver operating characteristic analysis showed that FICEΔE' was useful for differentiating between APs and HPs, with an area under the curve of 0.928 (95% confidence interval, 0.843-1). The sensitivity was 91.2%, and the specificity was 88.2% with a cut-off value of 1.758. Conclusion Using FICE on CCE images of CPs and applying the CIELAB color space method, we were able to differentiate between APs and HPs with high accuracy. This method has the potential to reduce unnecessary CS procedures.

Tag-less patency capsule for suspected small bowel stenosis: Nationwide multicenter prospective study in Japan.

STUDY AIMS: The PillCam patency capsule (PPC) is an Agile tag-less patency capsule used to evaluate gastrointestinal (GI) patency. We determined the appropriate use of PPC to preclude subsequent small bowel capsule endoscopy (SBCE) retention. METHODS: This prospective multicenter study consecutively enrolled patients indicated for SBCE with suspected or established small bowel stenosis. Excretion of an intact PPC or its radiologic visualization in the large bowel was considered GI patency. Primary and secondary study endpoints were SBCE retention rates in patients with confirmed patency and identification of factors associated with patency and SBCE retention, respectively. RESULTS: Of 1096 patients enrolled in the study, patency was confirmed in 976 (89.1%). PPC excretion occurred in 579 patients. Of the remaining 517 patients, patency was confirmed using imaging modalities in 401 (77.5%). SBCE retention occurred in five (0.51%) of 963 patients who underwent SBCE: 1.0% in established Crohn's disease (CD) patients, 0% in suspected CD, 0% in tumors, and 1.6% in patients with obscure GI bleeding, for which PPC localization had been radiographically misinterpreted. The non-confirmation of patency was associated with established CD, stenosis identified using imaging modalities, abdominal fullness, serum albumin levels <4.0 g/dL, and previous small bowel obstruction (adjusted odds ratios: 4.21, 2.60, 2.47, 2.12, and 2.00; 95% confidence intervals: 2.62-6.78, 1.62-4.17, 1.43-4.27, 1.32-3.40, and 1.15-3.47, respectively). CONCLUSIONS: The PillCam™ patency capsule helped preclude SBCE retention in most patients, but its accurate localization was essential for cases without excretion (Study registered the University Hospital Medical Information Network, #UMIN000010513).

Evaluation of the impact of linked color imaging for improving the visibility of colonic polyp.

Linked color imaging (LCI) is a novel endoscopic system used to increase color contrast. As LCI does not decrease luminal brightness, it may improve the detection of colonic neoplasms. However, the extent to which LCI improves the visibility of colonic polyps has not yet been determined. Between December 2016 and May 2017, patients who received total colonoscopy were consecutively recruited into this retrospective, single-center study. For each polyp identified, images obtained from white light (WL) imaging, blue laser imaging (BLI), and LCI of the same lesion and its surrounding mucosa were evaluated. The color differences (ΔE) between each lesion and its surrounding mucosa in non-magnified images were computed quantitatively using the CIELAB color space, which defines color perception according to colorimetric values, and compared among WL, BLI, LCI, and chromoendoscopy. The ΔE between the vessel and non-vessel areas in magnified images was also assessed. Of the 64 patients who were incorporated into this study, non-magnified and magnified (×80) images from 113 and 95 polyps, respectively, were assessed. The ΔE was intensified by LCI and chromoendoscopy compared with WL and BLI. The ΔE of neoplastic lesions was also intensified by LCI. In magnified images, BLI and LCI significantly increased the ΔE between the vessel and non-vessel areas compared with WL. Luminal brightness, indicated by L*, was not impaired by LCI; however, was reduced by BLI compared with WL and LCI. These results suggest that LCI enhanced the detection of colonic neoplasms without impairing luminal brightness. We propose the routine use of LCI for colonic polyp detection and BLI for magnifying observations of colonic polyps detected by LCI.

Massive Bleeding from a Small Intestinal Submucosal Tumor-like Arterial Malformation: An Unclassifiable Vascular Lesion Revealed by a Detailed Pathological Evaluation.

A 53-year-old woman presented with repeated copious bloody stool. Small bowel capsule endoscopy revealed a submucosal tumor (SMT)-like lesion, with erosion of the surface, in the first third of the small bowel. Balloon-assisted small intestinal endoscopy also revealed a pulsatile SMT-like lesion with an exposed vessel on the surface. This unknown lesion was surgically resected. The histopathological findings of the resected SMT-like lesion showed a dilated artery with thrombosis blockage and recanalization. Since this case could not be classified as any of the small intestinal vascular lesion patterns endoscopically, its classification will require the accumulation of further cases.

Preventive effect of ecabet sodium on low-dose aspirin-induced small intestinal mucosal injury: a randomized, double-blind, pilot study.

BACKGROUND: We aimed to investigate how high-dose ecabet sodium affects low-dose aspirin-induced small intestinal mucosal injury in healthy volunteers. METHODS: Healthy volunteers were enrolled randomly into one of two groups with the following drug regimens for 2 weeks: group A, low-dose aspirin once per day and group B, low-dose aspirin and 4.0 g of ecabet sodium. Small bowel capsule endoscopy was performed before and 2 weeks after low-dose aspirin administration. RESULTS: A significant difference was found in the median number [range] of small intestinal lesions between baseline and two weeks after low-dose aspirin administration in group A (baseline: 1 [0-5], after: 5 [1-11]; p = 0.0059) but not in group B (baseline: 0.5 [0-9], after: 3 [0-23]; p = 0.0586). In group B, although the median number [range] of lesions in the first tertile of the small intestine did not increase two weeks after low-dose aspirin administration (baseline: 0 [0-4], after: 1.5 [0-8]; p = 0.2969), the number of lesions in the second and third tertiles of the small intestine increased significantly (baseline: 0 [0-5], after: 2 [0-15]; p = 0.0469). CONCLUSIONS: Ecabet sodium had a preventive effect on low-dose aspirin-induced small intestinal mucosal injury in the upper part of the small intestine. TRIAL REGISTRATION: ISRCTN 99322160 , 01/10/2018.

Superficial non-ampullary duodenal cancer identified by small-bowel capsule endoscopy: a case report (with video).

Herein, we report for the first time a case of a surficial superficial non-ampullary duodenal cancer causing obscure intestinal bleeding that was identified by small-bowel capsule endoscopy and treated by endoscopic mucosal resection. A 73-year-old man underwent upper gastrointestinal endoscopy to identify the cause of anemia. Although conventional duodenoscopy revealed a flat, elevated 5-mm lesion with a central recess and "milk-white mucosa" at the inferior duodenal angulus, capsule endoscopy revealed a white nodular 5-mm lesion with central recess at the duodenum slightly to the anal side from the major duodenal papilla. Pathohistological examination revealed a low-grade well-differentiated tubular adenocarcinoma growing locally in the mucosal layer. Although capsule endoscopy detected a nodular lesion, conventional endoscopy revealed a flat, elevated lesion. The cause of this difference in endoscopic findings is considered to be the degree of extension of the intestinal mucosa. In contrast, "milk-white mucosa" as a typical finding of superficial duodenal tumor in conventional endoscopy could be identified as a white mucosal color tone in capsule endoscopy. Conventional endoscopic findings of irregular surface structure in the lesion suggested malignancy. Pathohistologically, the ductal structure of the adenocarcinoma was also distorted. Unfortunately, it was difficult to suggest that the lesion was adenocarcinoma based on the endoscopic findings alone.

Capsule endoscopy findings for the diagnosis of Crohn's disease: a nationwide case-control study.

BACKGROUND: Capsule endoscopy can be used to identify the early stage of small bowel Crohn's disease (CD). We evaluated significant small bowel capsule endoscopy (SBCE) findings that can lead to early diagnosis of CD. METHODS: We retrospectively accumulated clinical and SBCE data of 108 patients (63 with and 45 without CD). Types of small bowel mucosal injuries, including erosion, ulceration, and cobblestone appearance, and the alignment of diminutive lesions were compared between patients with and without CD. Inter- and intra-observer agreement in the determination of lesions was assessed in 25 pairs of SBCE from the two groups. RESULTS: Under SBCE, cobblestone appearance (33% vs. 2%, p < 0.0001), longitudinal ulcers (78% vs. 20%, p < 0.0001), and irregular ulcers (84% vs. 60%, p < 0.01) were more frequently found in patients with CD. Linear erosion (90% vs. 38%, p < 0.0001) and irregular erosion (89% vs. 64%, p < 0.005) were also more frequent in patients with CD. Furthermore, circumferential (75% vs. 9%, p < 0.0001) and longitudinal (56% vs. 7%, p < 0.0001) alignment of diminutive lesions, mainly observed in the 1st tertile of the small bowel, was more frequent in patients with CD. Good intra-observer agreement was found for ulcers, cobblestone appearance, and lesion alignment. However, inter-observer agreement of SBCE findings differed among observers. CONCLUSIONS: Circumferential or longitudinal alignment of diminutive lesions, especially in the upper small bowel, may be a diagnostic clue for CD under SBCE, while inter-observer variations should be cautiously considered when using SBCE.

Dual antiplatelet therapy does not affect the incidence of low-dose aspirin-induced small intestinal mucosal injury in patients after percutaneous coronary intervention for coronary stenosis: a multicenter cross-sectional study.

Although low-dose aspirin (LDA) is known to induce small intestinal mucosal injury, the effect of dual antiplatelet therapy (DAPT; LDA + clopidogrel) on small intestinal mucosa in patients after percutaneous coronary intervention (PCI) for coronary stenosis is unknown. Fifty-one patients with a history of PCI and LDA use were enrolled, and 45 eligible patients were analyzed. Patients were grouped based on DAPT (DAPT: n = 10 and non-DAPT: n = 35) and proton pump inhibitor (PPI) use (PPI user: n = 22 and PPI-free patients: n = 23) to compare small intestinal endoscopic findings. The relationship between LDA-use period and small intestinal endoscopic findings was also examined. Multivariate analysis was performed to identify risk factors for LDA-induced mucosal injury using age, sex, DAPT, PPI, gastric mucoprotective drug, and LDA-use period. The rate of small intestinal mucosal injury incidence did not significantly differ between DAPT and non-DAPT patients (50% vs 51.1%, respectively; p = 0.94), or PPI users and PPI-free patients (50% vs 52.2%, respectively; p = 0.88). Additionally, LDA-use period of ≤24 months (n = 15) yielded a significantly higher rate of small intestinal mucosal injury incidence than LDA-use period >24 months (n = 30) (80% vs 36.7%, respectively; p = 0.006). Multivariate analysis revealed that a LDA-use period of ≤24 months was a significant risk factor for small intestinal mucosal injury (odds ratio: 19.5, 95% confidence interval: 2.48-154.00, p = 0.005). Following PCI for coronary stenosis, neither DAPT nor PPI affected LDA-induced small intestinal mucosal injury. Moreover, patients who used LDA within the last 24 months were at a greater risk of small intestinal mucosal injury.

Cytomegalovirus infection in ulcerative colitis assessed by quantitative polymerase chain reaction: risk factors and effects of immunosuppressants.

We investigated the risk factors of and appropriate treatment for cytomegalovirus colitis in patients with ulcerative colitis, using quantitative polymerase chain reaction analysis to detect cytomegalovirus in the colonic mucosa. Between February 2013 and January 2017, patients with exacerbated ulcerative colitis who were admitted to our hospital were consecutively enrolled in this retrospective, single-center study. Patients were evaluated for cytomegalovirus using serology (antigenemia) and quantitative polymerase chain reaction analyses of the colonic mucosa, which were sampled during colonoscopy. Of 86 patients, 26 (30.2%) had positive quantitative polymerase chain reaction results for cytomegalovirus; only 4 were also positive for antigenemia. The ages of the cytomegalovirus DNA-positive patients were significantly higher than those of negative patients (p = 0.002). The mean endoscopic score of cytomegalovirus DNA-positive patients was significantly higher than that of cytomegalovirus DNA-negative patients. Treatment with combined immunosuppressants was associated with an increased risk of cytomegalovirus. Fourteen of 15 (93.3%) cytomegalovirus DNA-positive patients who were negative for antigenemia showed a clinical response to treatment with additional oral tacrolimus, without ganciclovir. cytomegalovirus reactivation in active ulcerative colitis is associated with age and combined immunosuppressant therapy. Because additional treatment with tacrolimus was effective, patients who are negative for antigenemia and cytomegalovirus DNA-positive colonic mucosa may recover without antiviral therapy.

Effect of egualen sodium hydrate on small-intestinal mucosal damage induced by low-dose aspirin: a prospective randomized clinical trial.

Low-dose aspirin, which is widely used to reduce the risk of cardio- and cerebrovascular thrombosis, often induces gastroenteropathy by increasing the permeability of the mucosa. However, therapeutic strategies for patients with low-dose aspirin-induced small intestinal injury have not been determined. We evaluated the preventative effect of egualen sodium hydrate, a gastro-protective agent that suppresses indomethacin-induced small-intestinal damage in rats, against small-intestinal mucosal damage induced by low-dose aspirin in healthy adult male volunteers. Participants were randomly allocated to receive aspirin 100 mg/kg daily (control group, n = 10) or aspirin 100 mg/kg plus egualen sodium 30 mg daily (egualen sodium group, n = 10). Small intestinal mucosal injury was evaluated by capsule endoscopy two weeks after initiation of drug administration. Fecal analyses (occult blood test, immunochemical test, transferrin measurement and calprotectin measurement) were carried out before and after treatment. Egualen sodium significantly suppressed the total number of small intestinal injuries detected by capsule endoscopy and the positive ratio for the fecal occult blood test. Daily use of 30 mg of egualen sodium showed a preventative effect on low-dose aspirin-induced small intestinal injury. Since acid suppression therapy was reported to exacerbate NSAIDs-induced enteropathy via dysbiosis, egualen sodium may be useful for patients treated with low-dose aspirin.

The Capsule Endoscopy Findings in S-1-induced Enteritis with Severe Diarrhea during Adjuvant Chemotherapy for Gastric Cancer (with Video).

Although S-1 chemotherapy is used widely as postoperative adjuvant chemotherapy for gastric cancer, some patients experience diarrhea during treatment. The patient was a 39-year-old woman who underwent distal gastrectomy for gastric cancer and who had started S-1 chemotherapy as postoperative adjuvant chemotherapy 1 week before her presentation. She experienced severe diarrhea immediately after starting the course of S-1 tablets. Capsule endoscopy revealed severe S-1-induced enteritis with extensive mucosal injury in the ileum and red intestinal fluid due to the oozing of blood in the ileum. After reducing the dosage of S-1, her diarrhea became milder, and she was able to continue S-1 chemotherapy.

Sitagliptin, a dipeptidyl peptidase-4 inhibitor, suppresses CXCL5 and SDF-1 and does not accelerate intestinal neoplasia formation in ApcMin/+ mice fed a high-fat diet.

The relationship between type 2 diabetes mellitus and intestinal neoplasia has been shown epidemiologically. A high-fat diet (HFD) is also known to promote insulin resistance, which is a risk factor for intestinal neoplasia. Dipeptidyl peptidase-4 (DPP-4) inhibitors are used in the clinic for the treatment of type 2 diabetes and also to prolong the effects of glucagon-like peptide-1 (GLP-1). However, since the intestinotrophic hormone GLP-2 and chemokines, such as CXCL5 and stromal cell-derived factor-1 (SDF-1), are also substrates of DPP-4, DPP-4 inhibitors may increase the risk of intestinal carcinogenesis. In this study, we evaluated the impact of a DPP-4 inhibitor on intestinal tumorigenesis in ApcMin/+ mice fed a HFD. Six-week-old male ApcMin/+ mice were randomized to either a normal diet (10 kcal% fat) group, a HFD (60 kcal% fat) group, or a HFD group treated with sitagliptin (STG). The mice were euthanized nine weeks after the start of treatment. Daily treatment with STG did not increase number of intestinal tumors in the HFD group; however, this increase was not statistically significant. The mucosal concentration of total GLP-2 was significantly increased in the HFD group. The chemokine protein array showed elevated plasma concentrations of CXCL5 and SDF-1 in the HFD group. The administration of STG significantly suppressed the levels of plasma CXCL5 and SDF-1 in mice fed a HFD. Since CXCL5 expression is increased in patients with type 2 diabetes, and GLP-2, CXCL5 and SDF-1 are associated with tumor progression, DPP-4 inhibition may have potential as an agent for decreasing the risk of cancer in obese or diabetic patients.

Determination of the adequate dosage of rebamipide, a gastric mucoprotective drug, to prevent low-dose aspirin-induced gastrointestinal mucosal injury.

Small intestinal mucosal injury caused by low-dose aspirin is a common cause of obscure gastrointestinal bleeding. We aimed to investigate the protective effects and optimal dose of rebamipide for low-dose aspirin-induced gastrointestinal mucosal injury. In this prospective randomized trial, 45 healthy volunteers (aged 20-65 years) were included and divided into three groups. The groups received enteric-coated aspirin 100 mg (low-dose aspirin) plus omeprazole 10 mg (Group A: proton pump inhibitor group), low-dose aspirin plus rebamipide 300 mg (Group B: standard-dose group), or low-dose aspirin plus rebamipide 900 mg (Group C: high-dose group). Esophagogastroduodenoscopy and video capsule endoscopy were performed, and the fecal occult blood reaction and fecal calprotectin levels were measured before and two weeks after drug administration. Although the fecal calprotectin levels increased significantly in Group A, they did not increase in Groups B and C. The esophagogastroduodenoscopic and video capsule endoscopic findings and the fecal occult blood test findings did not differ significantly among the three groups. In conclusion, standard-dose rebamipide is sufficient for preventing mucosal injury of the small intestine induced by low-dose aspirin, indicating that high-dose rebamipide is not necessary.

Multiple Mesenteric Panniculitis as a Complication of Sjögren's Syndrome Leading to Ileus.

Mesenteric panniculitis (MP) is a benign fibroinflammatory process characterized by the presence of fat necrosis, chronic inflammation and fibrosis in the mesentery. Although various causal factors, such as malignancy, chronic inflammatory conditions and autoimmune processes, have been identified, the precise etiology remains unknown. We herein report a rare case of MP accompanying Sjögren's syndrome in which a mass lesion and intestinal stenosis were observed simultaneously. This condition led to ileus, which was effectively treated using prednisolone.

The dipeptidyl peptidase-4 inhibitor sitagliptin suppresses mouse colon tumorigenesis in type 2 diabetic mice.

Patients with type 2 diabetes mellitus are known to have an increased risk of colorectal neoplasia. Dipeptidyl peptidase-4 (DPP-4) inhibitors have been used as a new therapeutic tool for type 2 diabetes. Since the substrates for DPP-4 include intestinotrophic hormones and chemokines such as GLP-2 and stromal cell-derived factor-1 (SDF-1), which are associated with tumor progression, DPP-4 inhibitors may increase the risk of colorectal tumors. However, the influence of DPP-4 inhibitors on colorectal neoplasia in patients with type 2 diabetes remains unknown. In the present study, we show that long-term administration of a DPP-4 inhibitor, sitagliptin (STG), suppressed colon carcinogenesis in leptin-deficient (ob/ob) C57BL/6J mice. Colonic mucosal concentrations of glucagon­like peptide-1 (GLP-1) and GLP-2 were significantly elevated in the ob/ob mice. However, mucosal GLP concentrations and the plasma level of SDF-1 were not affected by the administration of STG. Real­time PCR analysis revealed that colonic mucosal IL-6 mRNA expression, which was significantly upregulated in the ob/ob mice, was significantly suppressed by the long-term administration of STG. These results suggest that a DPP-4 inhibitor may suppress colon carcinogenesis in mice with type 2 diabetes in a GLP-independent manner. Since DPP-4 has multiple biological functions, further studies analyzing other factors related to colon carcinogenesis are needed.