A Follow-up Report on the Diagnosis of Gastrointestinal Cancer during the COVID-19 Pandemic in Akita Prefecture, Japan in 2021.

We recently reported the decrease in the number of gastrointestinal (GI) cancer diagnoses in 2020 due to disturbance of the healthcare system by the coronavirus disease 2019 (COVID-19) pandemic, using a hospital-based cancer registration system in Akita prefecture, Japan. In this study, we extended the research by showing the latest data (2021) on the number of cancers and examinations. Information on the occurrence and stage of esophageal, gastric, and colorectal cancers was collected from the same database. The number of GI examinations (cancer screening procedures and endoscopic examinations) was also investigated. Following the immediate decrease in the numbers of both GI examinations and GI cancer diagnoses in 2020, a rebound increase in the numbers of GI cancer diagnoses-especially colorectal cancers-was observed in 2021, resulting from an increased number of GI examinations i.e., the total number of colorectal cancers in 2021 increased by 9.0% and 6.8% in comparison to 2020 and pre-pandemic era, respectively. However, the rebound increase in 2021 was largely due to an increase in early-stage cancers, and there was no apparent trend toward the increased predominance of more advanced cancers. It therefore seems that we managed to escape from the worst-case scenario of disturbance of the healthcare system due to pandemic (i.e., an increase in the number of more advanced cancers due to delayed diagnoses). We need to continue to watch the trends in Akita prefecture, which has the highest rate of mortality from the 3 major GI cancers in Japan.

Limited endoscopic mucosal inflammation on equivalent to Mayo endoscopic subscore of 0 unaffect clinical relapse of ulcerative colitis.

BACKGROUND AND AIM: Mayo endoscopic subscore is a simple and validated endoscopic score for ulcerative colitis but the range of inflammation was not considered for scoring. There were few reports analyzing the range of inflammation for clinical relapse using Mayo endoscopic subscore (MES). The aim of this study is to investigate the relapsing potential of limited mucosal inflammation on endoscopic remission equivalent to MES of 0. METHODS: For this retrospective observational study, ulcerative colitis patients underwent total colonoscopy were enrolled. Small mucosal lesion (SML) was defined as limited inflammation of range less than 3 cm. Clinical relapse was analyzed using the Kaplan-Meier curve with log-rank test, and factors associated with clinical relapse was analyzed using the cox proportional hazard regression model. RESULTS: A total of 102 periods with mucosal healing or modified MES of 0 with SML were analyzed. In 12-months observation periods, clinical relapse occurred more frequently in MES of 1 than in MES of 0 or modified MES of 0 with SML, but it was comparable between MES of 0 and modified MES of 0 with SML. When compared to patients with modified MES of 0 with SML, the hazard ratio in patients with MES of 1 (6.55; p = .028) was significantly high but similar in those with MES of 0 (2.59; p = .29). CONCLUSIONS: Small mucosal inflammation in UC does not affect the clinical relapse if most of the mucosa achieved a score similar to MES of 0.

Diverse contributions of the visceral fat area to the etiology of two distinct subtypes of esophago-gastric junctional adenocarcinoma.

BACKGROUND: There are two distinct etiologies of esophago-gastric junctional adenocarcinomas (EGJACs): one associated with extensive gastric mucosal atrophy (GA), resembling non-cardiac gastric cancers; and the other related to gastro-esophageal reflux disease, resembling esophageal adenocarcinoma. In this study, we investigated the associations between the visceral fat area (VFA) and EGJACs separately in the two subtypes of EGJACs, depending on the extent of background GA. METHODS: Sixty-four consecutive patients with EGJACs (Siewert type 2) were enrolled from a population-based database in Akita Prefecture, Japan, between 2014 and 2019. Two age- and sex-matched healthy controls were randomly assigned to each EGJAC case. The extents of GA were evaluated endoscopically, and the VFA values were measured based on computed tomography images. Logistic regression analyses were performed to investigate the associations between EGJACs and the VFA. RESULTS: Study subjects were classified into 2 subgroups depending on the extent of endoscopic GA: 29 (45.3%) without and 35 (54.7%) with extensive GA. Multivariable regression analyses revealed that a VFA of ≥100 cm2 was significantly associated with EGJACs in subjects without extensive GA [odds ratio (95% confidence interval): 2.65 (1.08-6.54)], while there was no such association in subjects with extensive GA [odds ratio (95% confidence interval): 1.52 (0.60-3.83)]. CONCLUSIONS: The contribution of the VFA to the etiology of EGJACs seems to differ depending on the extent of background GA, with the VFA more prominently associated with EGJACs in subjects without extensive GA than in those with it, providing further rationale concerning the heterogeneous nature of EGJAC etiology.

Leucine-Rich Alpha-2 Glycoprotein in Monitoring Disease Activity and Intestinal Stenosis in Inflammatory Bowel Disease.

Leucine-rich alpha-2 glycoprotein (LRG) is a novel biomarker for monitoring disease activity in inflammatory bowel disease (IBD). The aim of this study was to evaluate its utility in monitoring disease activity. In this retrospective study based on case records between August 2020 and July 2021 at our two centers, we examined the correlation between serum levels of LRG and C-reactive protein (CRP) with disease activity in IBD patients. Background factors related to serum LRG levels were also analyzed. Overall, 47 Crohn's disease (CD) and 123 ulcerative colitis (UC) patients were evaluated. In patients with CD, LRG and CRP levels correlated with Harvey-Bradshaw Index (HBI) and Simple Endoscopic Score for CD (SES-CD) (LRG and HBI, r = 0.397; LRG and SES-CD, r = 0.637; CRP and HBI, r = 0.253; CRP and SES-CD, r = 0.332). In patients with UC, LRG and CRP significantly correlated with the partial Mayo score (PMS) and Mayo endoscopic subscore (MES) (LRG and PMS, r = 0.3; CRP and PMS, r = 0.282; LRG and MES, r = 0.424; CRP and MES, r = 0.459). In CD patients with normal CRP, serum LRG level was significantly higher in those with mucosal inflammation than in those with mucosal healing (16.4 vs. 10.7 µg/ mL). Stenosis was associated with serum LRG levels in CD group using multiple regression analysis. Therefore, LRG is a useful biomarker for monitoring disease activity and mucosal inflammation, and indicates the status of intestinal stenosis in IBD patients.

Visceral obesity is associated with an increased risk of developing esophago-gastric junctional adenocarcinoma in Japan: a population-based case-control study in Akita Prefecture.

BACKGROUND: While an association between esophago-gastric junctional adenocarcinomas (EGJACs) and obesity, especially visceral obesity, has been suggested in Western countries, the association remains unclear in Asia, including Japan. In this population-based case-control study, we investigated the association between EGJACs and obesity. METHODS: To perform near-population-based data collection for all early-stage EGJACs occurring in Akita Prefecture from 2014 to 2019, clinical data, including endoscopic and computed tomography (CT) findings, were collected from 11 cancer treatment base hospitals in the area. Age- and gender-matched controls were extracted at a case-to-control ratio of 1:2 from healthy subjects who received health checkups in the same area. The visceral fat area (VFA) was calculated using CT images. Logistic regression analyses were performed to investigate the associations between EGJACs and obesity-related parameters. RESULTS: In total, 74 EGJAC cases (62 males, median age of 70 years old) and 148 controls were extracted. Multivariable analyses showed a significantly negative association between the BMI and EGJACs and a significantly positive association between the VFA and EGJACs with odds ratios (ORs) (95% confidence intervals [CIs]) of 0.65 (0.53-0.80) and 1.01 (1.01-1.02), respectively. These findings were confirmed in another dataset (40 EGJACs and 80 controls). In addition, as a categorical variable, VFA ≥ 100 cm2 showed a significantly positive association with EGJACs (OR [95% CI] 1.96 [1.02-3.76]). CONCLUSIONS: We found paradoxical associations between EGJACs and obesity-related parameters (BMI vs. VFA) in a Japanese population, suggesting a potentially pivotal role of the VFA rather than the BMI as a risk factor for EGJACs.

Risk Factors Linking Esophageal Squamous Cell Carcinoma With Head and Neck Cancer or Gastric Cancer.

GOALS: To investigate retrospectively the risk factors for synchronous and metachronous cancers in the upper gastrointestinal tract in patients with superficial esophageal squamous cell carcinoma (ESCC). BACKGROUND: In patients who have received endoscopic resection (ER) for ESCC, synchronous and metachronous cancers are frequently detected not only in the esophagus but also in the head and neck area and the stomach. STUDY: A total of 285 patients who received ER for superficial ESCC were enrolled in this analysis. These patients were periodically followed-up endoscopically. Cumulative occurrence rates of the metachronous second primary cancers were determined by Kaplan-Meier method. Risk factors for synchronous and metachronous cancers in the head and neck area and the stomach were determined by logistic regression analyses. RESULTS: During a mean follow-up period of 76 months, the 5-year cumulative occurrence of metachronous esophageal, head and neck, and stomach cancer was 14.0%, 2.8%, and 4.1%, respectively. Although the presence of multiple lugol-voiding lesions in the esophagus was a significant risk factor for synchronous and metachronous head and neck cancers (odds ratio, 3.8; 95% confidence interval, 1.7-9.0), older age (>65 y) was a significant risk factor for synchronous and metachronous gastric cancer (odds ratio, 3.1; 95% confidence interval, 1.2-9.3). CONCLUSIONS: The risk factors for the cooccurrence of head and neck cancer and that of gastric cancer in patients with ESCC differ. This information will likely be useful for managing patients who have been treated with ER for ESCC and who possess carcinogenic potential throughout the upper gastrointestinal tract.

A Report of Ulcerative Colitis With Relapse on the Rectal Side of the Loop Sigmoid Colostomy and Not on the Oral Side.

A patient who received a loop sigmoid colostomy was diagnosed with ulcerative colitis (pancolitis type) and treated with infliximab. Thereafter, he relapsed with intestinal inflammation only on the rectal side of the loop sigmoid colostomy and not on the oral side. Autologous fecal microbiota transplantation from the proximal intestine to the distal intestine was performed to treat the inflammation but was ineffective. He was treated with oral prednisolone and induced into remission. After analyzing fecal samples from the patient, we observed an alteration of the composition of the intestinal microbiota with intestinal inflammation, including a reduction of phylum Firmicutes in the inflamed distal intestine, whereas Firmicutes was conserved in the proximal non-inflamed intestine and recovered in the distal intestine after induction of remission. Thus, our results indicated that the inflammation was associated with an alteration of the intestinal microbiota.

Helicobacter pylori Eradication Does Not Adversely Affect the Clinical Course of Gastric Cancer: A Multicenter Study on Screening Endoscopic Examination in Japan.

BACKGROUND: Since gastric cancers (GCs) detected after Helicobacter pylori (HP) eradication present with different morphological characteristics from conventional HP-positive GCs, delayed detection of early-stage GCs may be observed. This study aimed to investigate the clinical impact of HP eradication on diagnosing GC during screening endoscopy. METHODS: Eleven health checkup institutions in Japan participated in the present study. All GC cases newly diagnosed by screening endoscopy between January 2016 and December 2020 were included. After propensity score matching, multivariable regression analysis was performed to estimate the effect of HP eradication on deep tumor invasion among HP-eradicated and HP-positive GC cases. RESULTS: A total of 231 patients with GCs (134 HP-eradicated and 97 HP-positive cases) were enrolled. After propensity score matching, there were 81 cases in each group. The distribution of the depth of tumor invasion (pT1a, pT1b1, pT1b2, and pT2) between the HP-eradicated group and HP-positive group was similar (p = 0.82). In the propensity analysis, with HP-positive as the reference value, HP eradication was not significantly associated with T1b-T4-GCs and T1b2-T4-GCs, with odds ratios (95% confidence intervals) of 1.16 (0.48-2.81) and 1.16 (0.42-3.19), respectively. CONCLUSIONS: HP eradication does not adversely affect the clinical course of GCs, supporting the recommendation of HP eradication in screening programs to reduce the total number of GC cases without delaying diagnosis.

Prediction model of 3-year survival after endoscopic submucosal dissection for early gastric cancer in elderly patients aged ≥ 85 years: EGC-2 model.

PURPOSE: Little is known about the prognostic factors for survival after endoscopic submucosal dissection (ESD) in elderly patients with early gastric cancer (EGC). The aim of this study is to determine prognostic factors and a prediction model of 3-year survival after ESD for EGC in patients aged ≥ 85 years. METHODS: We retrospectively evaluated the clinical outcomes of 740 patients with EGC aged ≥ 85 years, who were treated by ESD at 30 institutions in Japan. Overall survival (OS) and disease-specific survival (DSS) were calculated with the Kaplan-Meier method. Prediction models for 3-year OS after ESD were estimated using the Cox proportional hazards model based on Uno's C-statistics. RESULTS: During the follow-up period, 309 patients died of any cause and 10 patients died of gastric cancer. OS and DSS after 3 years were 82.7% and 99.2%, respectively. No significant differences in OS were found among curability categories. The Cox proportional hazards model revealed the geriatric nutritional risk index (GNRI) and the Charlson comorbidity index (CCI) to be predictors of 3-year survival. We established a final model (EGC-2 model) expressed by GNRI - (2.2×CCI) with a cutoff value of 96. The overall survival rate was significantly lower in the model value < 96 group than in the model value ≥ 96 group (P < 0.001). CONCLUSIONS: The prediction model using GNRI and CCI will be useful to support decision-making for the treatment of EGC in elderly patients aged ≥ 85 years.

Treatment strategy after noncurative endoscopic resection for early gastric cancers in patients aged ≥ 85 years: a multicenter retrospective study in a highly aged area of Japan.

BACKGROUND: The guidelines recommend additional gastrectomy after noncurative endoscopic resection for early gastric cancers (EGCs). However, no additional treatment might be acceptable in some patients aged ≥ 85 years. We aimed to identify this patient group using the data in a highly aged area. METHODS: We enrolled patients aged ≥ 85 years after noncurative endoscopic resection for EGCs at 30 institutions of the Tohoku district in Japan between 2002 and 2017. Treatment selection and prognosis after noncurative endoscopic resection were investigated. Fourteen candidates were evaluated using the Cox model to identify risk factors for poor overall survival (OS) in patients with no additional treatment. RESULTS: Of 1065 patients aged ≥ 85 years, 143 underwent noncurative endoscopic resection. Despite the guidelines' recommendation, 88.8% of them underwent no additional treatment. The 5-year OS rates in those with additional gastrectomy and those with no additional treatment were 63.1 and 65.2%, respectively. Multivariate analysis showed independent risk factors for poor OS in patients with no additional treatment were the high-risk category in the eCura system (hazard ratio [HR], 2.91), Charlson comorbidity index (CCI) ≥ 3 (HR, 2.78), and male (HR, 2.04). In patients with no additional treatment, nongastric cancer-specific survival was low (69.0% in 5 years), whereas disease-specific survival rates were very high in the low- and intermediate-risk categories of the eCura system (100.0 and 97.1%, respectively, in 5 years). CONCLUSIONS: No additional treatment may be acceptable in the low- and intermediate-risk categories of the eCura system in patients aged ≥ 85 years with noncurative endoscopic resection for EGCs.

Effect of acid-reducing agents on clinical relapse in ulcerative colitis with pH-dependent-released 5-aminosalicylic acid: a multicenter retrospective study in Japan.

BACKGROUND/AIMS: 5-Aminosalicylic acid (5-ASA) is a basic drug for inducing and maintaining remission for ulcerative colitis. One of its formulations has a coating with a pH-dependent degradation that ensures the release 5-ASA at the terminal ileum. No evidence has been shown concerning the effects of proton pump inhibitors (PPIs) or H2 receptor antagonists (H2RAs) on the clinical course of ulcerative colitis patients in remission. The present study assessed the effect of PPIs or H2RAs on the relapse of ulcerative colitis patients in clinical remission maintained by pH-dependent released 5-ASA. METHODS: Ulcerative colitis patients who had been prescribed time- or pH-dependent-released 5-ASA between January 2015 and December 2018 were enrolled in this multicenter retrospective study. The period of remission until relapse occurred was analyzed among the patients taking time-dependent-released 5-ASA or pH-dependent-released 5-ASA with/without PPIs or H2RAs. RESULTS: One hundred and nineteen patients were analyzed in this study. In the primary endpoint, the relapse rate was higher in patients taking pH-dependent-released 5-ASA and PPIs or H2RAs than in those taking the pH-dependent-released 5-ASA without PPIs or H2RAs, while the relapse rate was similar in patients taking the time-dependent-released 5-ASA with or without PPIs or H2RAs concomitantly. Patients with a short duration of disease and middle-aged patients more frequently showed relapse with PPIs or H2RAs than the other patients. CONCLUSIONS: The coadministration of PPIs or H2RAs affects the clinical course of ulcerative colitis in remission maintained by pH-dependent-released 5-ASA.

Impact of a transparent hood on the performance of total colonoscopy: a randomized controlled trial.

BACKGROUND: Clinical demand for total colonoscopy (TCS) is increasing. Improvement of the cecal intubation rate and shortening of the examination time would expand the capacity for TCS. OBJECTIVE: To assess the efficacy of a transparent hood attached to the tip of a colonoscope for cecal intubation in TCS. DESIGN: Prospective, randomized, controlled study. SETTING: Single tertiary-referral center. INTERVENTIONS: TCS. MAIN OUTCOME MEASUREMENTS: Cecal intubation time and rate, complications, patient discomfort, and detection rate of colonic polyps. METHODS: Patients who were to undergo screening and/or surveillance TCS for colorectal cancer were invited to participate in the study. Cecal intubation time and rate, complications, patient discomfort, and detection rate of colonic polyps were evaluated. RESULTS: A total of 592 patients enrolled in this study were randomly allocated to the hood group and no-hood group. The mean (SD) cecal intubation time in the hood group and the no-hood group was 10.2 +/- 12.5 minutes and 13.4 +/- 15.8 minutes, respectively (P = .0241). The effect of its use was more prominent in the expert endoscopists group compared with those with moderate experience. The cecal intubation rate and the detection rate of small polyps in the 2 groups were similar. The grade of patient discomfort was significantly lower in the hood group. No complications were encountered with the use of the hood. CONCLUSIONS: Use of a transparent hood on the tip of a colonoscope shortened the time required for cecal intubation and decreased patient discomfort; such use was more effective among experts in shortening the examination time.

Long-tube insertion with the ropeway method facilitated by a guidewire placed by transnasal ultrathin endoscopy for bowel obstruction: a prospective, randomized, controlled trial.

BACKGROUND: It is often difficult to insert a long intestinal tube in the small bowel of patients with bowel obstruction, and it often results in long procedure time and severe patient distress. OBJECTIVE: To assess the usefulness of the ropeway method by using a guidewire placed with the assistance of transnasal ultrathin endoscopy in long-tube insertion for patients with bowel obstruction. DESIGN: Prospective, randomized, controlled, single-center study. PATIENTS AND INTERVENTIONS: Thirty-four consecutive patients with bowel obstruction requiring decompression participated in the study and were randomized to the insertion of a long tube with the ropeway method (ILTR) group (ie, insertion along an endoscopically placed guidewire that was passed through only the distal 4 cm of the tube) or insertion by a conventional method group (C group). MAIN OUTCOME MEASUREMENTS: The time required for the procedure (main), success rate, x-ray exposure time, and intensity of patient distress measured with a visual analog scale of 1 to 5 (better to worse). RESULTS: The mean (+/- standard deviation) duration of the procedure in the successful cases in the ILTR group and the C group was 16.1 +/- 5.6 minutes and 26.4 +/- 13.8 minutes, respectively (P = .010). The success rate was 100% in the ILTR group and 88% in the C group (P = .48). The mean (+/- standard deviation) x-ray exposure time and intensity of patient distress were, respectively, 16.4 +/- 8.7 minutes and 33.2 +/- 12.3 minutes (P < .001) and 2.6 +/- 0.7 and 3.7 +/- 1.2 (P = .016). LIMITATIONS: Single-center study and small sample size to evaluate overall safety. CONCLUSIONS: Long-tube insertion for bowel obstruction with the ropeway method facilitated by transnasal ultrathin endoscopy was superior to conventional fluoroscopic placement with regard to overall procedure success, time required, and patient comfort.

Long intestinal tube insertion with the ropeway method facilitated by a guidewire placed by transnasal ultrathin endoscopy for bowel obstruction.

AIM: For patients with bowel obstruction, intestinal decompression by a long tube is recommended. We assessed the usefulness of a new technique for insertion of a long tube with a guidewire placed by transnasal ultrathin endoscopy. METHODS: Nineteen patients who had been diagnosed as suffering from bowel obstruction underwent long-tube insertion with the ropeway technique using a guidewire placed by transnasal endoscopy. Thirty-three patients who had undergone conventional insertion of a long tube were included as controls. The success rate of intubation of the small bowel and the time required for the procedure were compared between the subjects and controls. RESULTS: The success rate of intubation was 94.7% (18/19) in subjects and 84.8% (28/33) in controls (P = 0.53). The time required for insertion in the subjects and controls was 24.1 +/- 8.1 min and 48.7 +/- 25.3 min, respectively, with a statistically significant difference (P < 0.001). No complications relevant to the procedure were encountered in either of the groups. CONCLUSION: Long-tube insertion facilitated by transnasal endoscopy reduces the time required for insertion in comparison with the conventional technique without endoscopy. Endoscopy-assisted long-tube insertion with the ropeway method is a safe and useful procedure for decompression in patients with bowel obstruction.

Is the new potent acid-inhibitory drug vonoprazan effective for healing idiopathic peptic ulcers? A multicenter observational study in Akita Prefecture, Japan.

BACKGROUND: The incidence of peptic ulcers unrelated to H. pylori infection and non-steroidal anti-inflammatory drugs (NSAIDs), termed idiopathic peptic ulcers (IPUs), has increased worldwide. We recently reported that IPUs were refractory to proton pump inhibitor (PPI) treatment. Vonoprazan, which was recently developed in Japan, has shown a more potent acid-inhibitory effect than ordinary PPIs. In the present study, we compared the healing rates among peptic ulcers of different etiologies following treatment with vonoprazan. METHOD: A multicenter observational study was performed at six participating hospitals in Akita Prefecture, Japan. Consecutive patients who had endoscopically confirmed gastro-duodenal ulcers were enrolled between August 2016 and March 2018. For each patient, the Helicobacter pylori infection status and NSAID use, including aspirin, were checked, and 20 mg vonoprazan was administered for 6 weeks for duodenal ulcers and 8 weeks for gastric ulcers. The healing status was checked by endoscopy at the end of vonoprazan treatment. Patients were divided into four subgroups according to the H. pylori status and NSAID usage. RESULTS: The proportion of IPUs was 18.2%. A total of 162 patients completed the study protocol. The healing rate of IPUs was marginally lower than that of simple H. pylori-associated ulcers (81.2% vs. 93.5%, P = 0.05). Similarly, the healing rate of NSAID-related ulcers, irrespective of concomitant H. pylori infection, was significantly lower than that of simple H. pylori-associated ulcers. CONCLUSIONS: Six- or 8-week vonoprazan treatment still seems to be insufficient for healing IPUs. Longer-term vonoprazan or another treatment option may be required to heal potentially refractory peptic ulcers.

Amylase levels in bile in patients with a morphologically normal pancreaticobiliary ductal arrangement.

BACKGROUND: We investigated the presence of occult pancreaticobiliary reflux in patients with a morphologically normal pancreaticobiliary ductal arrangement by measuring biliary amylase levels and compared histopathological findings of the gallbladder between groups with high and low biliary amylase levels. METHODS: In 178 patients with a normal pancreaticobiliary ductal arrangement who had undergone endoscopic retrograde cholangiopancreatography (ERCP), we sampled bile from the bile duct and measured amylase levels. Then we compared clinical features and histological findings of the gallbladder between high (HALG) and low amylase level groups (LALG). RESULTS: A high biliary amylase level was observed in 25.8% (46/178) of the patients. The prevalence of a high biliary amylase level was high in patients with gallbladder carcinoma (40%) and in those with choledocholithiasis (28.4%). The level of amylase in bile was high in patients with gallbladder carcinoma, adenomyomatosis of the gallbladder, and chronic cholecystitis. A strong correlation between the levels of amylase and lipase in bile and the dominance of amylase of pancreatic origin in bile were confirmed by isozyme analysis. Thickening of the gallbladder mucosa was a significant manifestation in HALG. Histological examination of the gallbladder mucosa showed that incidences of metaplastic change and atypical epithelium and Ki67-LI in were higher in HALG than in LALG. CONCLUSIONS: Occult pancreaticobiliary reflux is observed in a considerable number of ERCP candidates. Those who show an extremely high biliary amylase level, at least, may be at high risk for biliary malignancies.

Clinicopathological study on the intraductal spread of small pancreatic cancer.

BACKGROUND: The aim of this study was to evaluate histopathologically the frequency, direction, and length of intraductal spread (IS) along the main pancreatic duct from the main tumor of small pancreatic cancer. METHODS: Resected specimens from 20 cases of pTS1 (histologically 2 cm or less in diameter) pancreatic cancer (September 1983 to December 2005) were examined histopathologically. As controls, 40 resected specimens from cases of pTS2 (more than 2 cm and less than 4 cm in diameter) or larger sized pancreatic cancer (pTS2