Immunohistochemical and molecular features of sporadic and FAP-associated duodenal adenomas of the ampullary and nonampullary mucosa. Am J Surg Pathol. 2008;32:1388-1395. [PMID: 18670349 DOI: 10.1097/pas.0b013e3181723679]

Cold-snare endoscopic resection of non-ampullary duodenal adenomas: Systematic review and pooled-analysis

BACKGROUND

Mirroring the experience with colonic resections, cold snare-based techniques have been recently proposed for non-ampullary duodenal lesions to reduce the risk of adverse events (AEs). As the duodenal wall is thinner and more vascularized than in the colon, electrocautery-related AEs are relevant issues in this setting.

AIMS

We performed a systematic review with pooled-analysis to evaluate the efficacy and safety of this technique.

METHODS

Electronic databases (Medline, Scopus, EMBASE) were searched up to January 2023. Full articles including patients with duodenal lesions resected by cold-snare technique were eligible. The adverse events (i.e., bleeding, perforation, stricture), complete resection, and recurrence rates were pooled using a random model.

RESULTS

Eleven studies were eligible, providing data on 3137 lesions removed from 233 patients. The overall AE rate for cold snaring was 0.25% (95% CI, 0.19%-0.69%). Among the three studies comparing cold- and hot-snare approaches, procedure-related bleeding rate was significantly lower with cold approach (OR 1.21, 0.51-2.85; p = 0.66). The complete resection rate was 99.40% (95% CI, 98.60%-100%), with a residual/recurrence rate of 12.95% (95% CI, 4.75%-21.16%). On univariate meta-regression, lesion size significantly affected both the adverse events and recurrence risk.

CONCLUSION

Cold-snare resection appears effective and extremely safe for resecting non-ampullary duodenal lesions.

Non-Pure Intestinal Phenotype as an Indicator of Progression in Sporadic Nonampullary Duodenal Adenomas: A Multicenter Retrospective Cohort Study

INTRODUCTION

We aimed to evaluate the natural course of sporadic nonampullary duodenal adenomas (SNDAs) and determine the risk factors of progression.

METHODS

We retrospectively analyzed the follow-up outcomes of patients with biopsy-diagnosed SNDA between April 2010 and March 2016 at 13 institutions. All initial biopsy specimens were centrally evaluated. Only those diagnosed with adenomas were included. Mucinous phenotypes were classified into pure intestinal and non-pure intestinal phenotypes. Cumulative incidence rates of carcinoma and tumor enlargement were evaluated. Tumor enlargement was defined as a ≥25% or 5-mm increase in tumor size.

RESULTS

Overall, 121 lesions were analyzed. Within a median observation period of 32.7 months, 5 lesions were diagnosed as carcinomas; the cumulative 5-year incidence of carcinoma was 9.5%. Male sex ( P = 0.046), initial lesion size ≥10 mm ( P = 0.044), and non-pure intestinal phenotype ( P = 0.019) were significantly associated with progression to carcinoma. Tumor enlargement was observed in 22 lesions, with a cumulative 5-year incidence of 33.9%. Initial lesion size ≥10 mm ( P < 0.001), erythematous lesion ( P = 0.002), high-grade adenoma ( P = 0.002), Ki67 negative ( P = 0.007), and non-pure intestinal phenotype ( P = 0.001) were risk factors of tumor enlargement. In a multivariate analysis, an initial lesion size ≥10 mm ( P = 0.010) and non-pure intestinal phenotype ( P = 0.046) were independent and significant risk factors of tumor enlargement.

DISCUSSION

Lesion size ≥10 mm and non-pure intestinal phenotype on initial biopsy are risk factors of cancer progression and tumor enlargement in cases with SNDA. Thus, management effectiveness may be improved by focusing on lesion size and the mucinous phenotype.

Endoscopic diagnosis and treatment of superficial non-ampullary duodenal epithelial tumors: A review

The surface of the small bowel mucosa is covered more than any other section of the digestive canal; however, the overall prevalence of small bowel tumors of the whole gastrointestinal tract is evidently low. Owing to the improvement in endoscopic techniques, the prevalence of small bowel tumors has increased across multiple countries, which is mainly due to an increase in duodenal tumors. Superficial non-ampullary duodenal epithelial tumors (SNADETs) are defined as tumors originating from the non-ampullary region in the duodenum that share similarities and discrepancies with their gastric and colorectal counterparts in the pathogenesis and clinicopathologic characteristics. To date, white light endoscopy (WLE) remains the cornerstone of endoscopic diagnosis for SNADETs. Besides, narrow-band imaging (NBI) techniques and magnifying endoscopy (ME) have been widely used in the clinic and endorsed by multiple guidelines and consensuses for SNADETs' evaluation. Confocal laser endomicroscopy (CLE), endocytoscopy (ECS), and artificial intelligence (AI) are also up-and-coming methods, showing an exceptional value in the diagnosis of SNADETs. Similar to the endoscopic treatment for colorectal polyps, the choices for SNADETs mainly include cold snare polypectomy (CSP), endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), and laparoscopic endoscopic cooperative surgery (LECS). However, owing to the narrow lumen, rich vascularity, weak muscle layer, abundant Brunner's gland, and the hardship of endoscope control, the duodenum ranks as one of the most dangerous operating areas in the digestive tract. Therefore, endoscopists must anticipate the difficulties in endoscopic maneuverability, remain aware of the increased risk of complications, and then select the appropriate treatment according to the advantages and disadvantages of each method.

Microsatellite instability in the high-grade dysplasia component of duodenal adenoma is associated with progression to adenocarcinoma

PURPOSE

We examined the microsatellite instability of duodenal tumors to evaluate their molecular features associated with the adenoma-carcinoma sequence.

METHODS

Fifty-two non-ampullary duodenal epithelial tumors collected by endoscopic mucosal resection or surgical resection were studied. When a tumor had two or more dysplasia grades, the highest grade was considered. Representative areas were macro-dissected and subjected to a microsatellite instability analysis and immunohistochemical staining.

RESULTS

The 52 tumors were classified as either adenoma with low-grade dysplasia (n = 18), adenoma with high-grade dysplasia (n = 20), or adenocarcinomas (n = 14). Among these, 3 adenocarcinoma cases showed microsatellite instability and the remaining 49 tumors showed microsatellite stability. Of the 14 adenocarcinoma cases, 3 contained both high-grade dysplasia and adenocarcinoma components, and 11 contained only the adenocarcinoma component. Interestingly, all three adenocarcinoma + high-grade dysplasia cases were microsatellite instability-high in both the adenocarcinoma and high-grade dysplasia components. Immunohistochemical staining of mismatch repair proteins showed mismatch repair deficiency in three microsatellite instability-high adenocarcinoma + high-grade dysplasia cases.

CONCLUSIONS

Only adenocarcinoma cases with high-grade dysplasia components were microsatellite instability-high (in both the adenocarcinoma and high-grade dysplasia components). This suggests that microsatellite instability in the high-grade dysplasia component of duodenal adenoma is associated with progression to adenocarcinoma.

Relationship between gene mutations and clinicopathological features in nonampullary duodenal epithelial tumors

BACKGROUND

Molecular features of nonampullary duodenal epithelial tumors (NADETs) remain unclear.

AIM

The aim of this study is to determine the association between the genetic features and clinicopathological findings of NADETs.

METHODS

In total, 75 NADETs were enrolled in this study, and was performed targeted DNA sequencing of the GNAS, KRAS, TP53, and APC genes. Histological grade was classified as category 3 or category 4/5 according to the Vienna classification, and the immunophenotype was categorized as the gastric phenotype (G type), gastrointestinal phenotype (GI type), or the intestinal phenotype (I type).

RESULTS

The prevalence of GNAS and KRAS mutations was significantly higher in the G type than in the GI/I type (GNAS, P = 0.027; KRAS, P = 0.005). In contrast, the frequency of TP53 mutations was significantly higher in the GI/I type than in the G type (P = 0.049). Notably, APC mutations, excluding c.4479 G>A which was synonymous mutation, were more frequently identified in category 4/5 tumors than in category 3 tumors (50% vs. 24.5%; P = 0.039).

CONCLUSION

G-type NADETs harbored frequent GNAS and KRAS mutations, whereas TP53 mutations are common in NADETs with intestinal features. APC mutations were significantly associated with high-grade neoplasia and invasive carcinoma.

Outcomes of cold snare piecemeal EMR for nonampullary small-bowel adenomas larger than 1 cm: a retrospective study

BACKGROUND AND AIMS

Nonampullary small-bowel adenomas ≥10 mm are typically resected using cautery-based polypectomy, which is associated with significant adverse events. Studies have demonstrated the safety and efficacy of piecemeal cold snare EMR for removing large colon polyps. Our aim was to assess the safety and efficacy of cold snare EMR for removal of large adenomas in the small bowel.

METHODS

A retrospective study of patients who underwent lift and piecemeal cold snare EMR of small-bowel adenomas ≥1 cm between January 2014 and March 2019 was conducted at a tertiary care medical center. Polyp characteristics at the time of index and surveillance endoscopy were collected. Primary outcomes were residual or recurrent adenoma (RRA) seen on surveillance endoscopy, polyp eradication rate, and number of endoscopic procedures required for eradication. Adverse events including immediate and delayed bleeding, perforation, stricture, pancreatitis, and postpolypectomy syndrome were assessed.

RESULTS

Of 43 patients who underwent piecemeal cold snare EMR, 39 had follow-up endoscopy. Polyps ranged in size from 10 to 70 mm (mean, 26.5 mm). RRA was found in 18 patients (46%), with increased polyp size correlating with higher recurrence (P < .001). Polyp eradication was observed in 35 patients (89%), requiring a median of 2 (range, 1-6) endoscopic procedures. Only 1 patient (2.3%) had immediate postprocedural bleeding. No cases of perforation or postpolypectomy syndrome were seen.

CONCLUSIONS

Piecemeal cold snare EMR may be a feasible, safe, and efficacious technique for small-bowel polyps >10 mm. Prospective, randomized studies are needed to assess how outcomes compare with traditional cautery-based polypectomy.

The impact of the age-adjusted Charlson comorbidity index as a prognostic factor for endoscopic papillectomy in ampullary tumors

BACKGROUND

The prognostic nutritional index (PNI) and Charlson comorbidity index (CCI) have been useful for predicting the prognosis based on nutritional condition and comorbidities in surgery and endoscopic mucosal dissection. The age-adjusted CCI (ACCI) has also been reported to be useful in surgery, but it has not been applied to endoscopic treatment. We therefore clarified the prognostic factors associated with ampullary tumors treated with endoscopic papillectomy (EP).

METHODS

From January 2003 to December 2020, 236 patients who underwent EP for sporadic ampullary tumors at Nagoya University Hospital were included in this study. The 5-year survival and ability to predict the prognosis were evaluated in terms of the sex, PNI, ACCI, final pathological diagnosis, and intraductal extension.

RESULTS

During a median follow-up period of 1558 days, 17 patients died. No patient died of the primary disease. The 5-year survival rate was 91.1%. In a univariate analysis, only a high ACCI (≥ 5) was extracted as a significant prognostic factor (Odds ratio, 12.2; 95% confidence interval, 3.81-39.3; p < 0.001). The 5-year survival rates for a low ACCI (≤ 4) and high ACCI were 96.6% and 73.5%, respectively (p < 0.001).

CONCLUSIONS

A high ACCI is an important prognostic factor associated with the 5-year survival and a risk of death from other illness. Ampullary tumors suitable for EP are less likely to be a prognostic factor, and treatment-free follow-up may be acceptable in patients with a high ACCI.

Endoscopic management of non-ampullary duodenal adenomas

Duodenal polyps are found in 0.1 % to 0.8 % of all upper endoscopies. Duodenal adenomas account for 10 % to 20 % of these lesions. They can be sporadic or occur in the setting of a hereditary predisposition syndrome, mainly familial adenomatous polyposis. Endoscopy is the cornerstone of management of duodenal adenomas, allowing for diagnosis and treatment, primarily by endoscopic mucosal resection. The endoscopic treatment of duodenal adenomas has a high morbidity, reaching 15 % in a prospective study, consisting of bleeding and perforations, and should therefore be performed in expert centers. The local recurrence rate ranges from 9 % to 37 %, and is maximal for piecemeal resections of lesions > 20 mm. Surgical resection of the duodenum is flawed with major morbidity and considered a rescue procedure in cases of endoscopic treatment failures or severe endoscopic complications such as duodenal perforations. In this paper, we review the existing evidence on endoscopic diagnosis and treatment of non-ampullary duodenal adenomas.

Histologic heterogeneity and syndromic associations of non-ampullary duodenal polyps and superficial mucosal lesions

BACKGROUND

Duodenal polyps and superficial mucosal lesions (DP/SMLs) are poorly characterised.

AIMS

To describe a series of endoscopically-diagnosed extra-ampullary DPs/SMLs.

METHODS

This is a retrospective study conducted in a tertiary referral Endoscopy Unit, including patients who had DPs or SMLs that were biopsied or removed in 2010-2019. Age, gender, history of familial polyposis syndromes, DP/SML characteristics were recorded. Histopathological, immunohistochemical and molecular analyses were performed.

RESULTS

399 non-ampullary DP/SMLs from 345 patients (60.6% males; median age 67 years) were identified. Gastric foveolar metaplasia represented the most frequent histotype (193 cases, 48.4%), followed by duodenal adenomas (DAs; 77 cases, 19.3%). Most DAs (median size 6 mm) were sessile (Paris Is; 48%), intestinal-type (96.1%) with low-grade dysplasia (93.5%). Among syndromic DAs (23%), 15 lesions occurred in familial adenomatous polyposis 1, two were in MUTYH-associated polyposis and one was in Peutz-Jeghers syndrome (foveolar-type, p53-positive, low-grade dysplasia). Only one (3.3%) tubular, low-grade DA showed mismatch repair deficiency (combined loss of MLH1 and PMS2, heterogeneous MSH6 expression), and it was associated with a MLH1 gene germline mutation (Lynch syndrome).

CONCLUSION

DPs/SMLs are heterogeneous lesions, most of which showing foveolar metaplasia, followed by low-grade, intestinal-type, non-syndromic DAs. MMR-d testing may identify cases associated with Lynch syndrome.

APC mutations are common in adenomas but infrequent in adenocarcinomas of the non-ampullary duodenum

BACKGROUND

Recent studies highlighted the clinicopathological heterogeneity of non-ampullary duodenal adenomas and adenocarcinomas, but the detailed process of the malignant transformation remains unclear.

METHODS

We analyzed 144 adenomas and 54 adenocarcinomas of the non-ampullary duodenum for immunohistochemical phenotypes, genetic alterations, and mismatch repair (MMR) status to probe their histogenetic relationship.

RESULTS

The median ages of patients with adenoma and adenocarcinoma were the same (66 years). Adenomas were histologically classified as intestinal-type adenoma (n = 124), pyloric gland adenoma (PGA, n = 10), gastric-type adenoma, not otherwise specified (n = 9), and foveolar-type adenoma (n = 1). Protein-truncating APC mutations were highly frequent in adenomas (85%), with the highest prevalence in intestinal-type adenomas (89%), but rare in adenocarcinomas (9%; P = 2.1 × 10^-23). Close associations between phenotypic marker expression and genetic alterations were observed in adenomas, but not in adenocarcinomas, excluding the common association between GNAS mutations and MUC5AC expression. MMR deficiency was more frequent in adenocarcinomas (20%) than in adenomas (1%; P = 2.6 × 10^-6). One MMR-deficient adenoma and three MMR-deficient adenocarcinomas occurred in patients with Lynch syndrome. Additionally, three other patients with an MMR-deficient adenocarcinoma fulfilled the revised Bethesda criteria.

CONCLUSION

The discrepant APC mutation frequency between adenomas and adenocarcinomas suggests that APC-mutated adenomas, which constitute the large majority of non-ampullary duodenal adenomas, are less prone to malignant transformation. Non-ampullary duodenal adenocarcinomas frequently exhibit MMR deficiency and should be subject to MMR testing to determine appropriate clinical management, including the identification of patients with Lynch syndrome.

Brunner's Gland Hamartoma of the Duodenum: A Literature Review

Brunner's gland hamartoma is a benign tumor of the duodenum, but has malignant potential with a very low risk of progression into adenocarcinoma. It is uncommon with a frequency of less than 1.0% among the primary tumors of the small intestine. In addition, its clinical manifestations are nonspecific, etiology remains unclear, and treatment strategy needs to be further refined. This literature review mainly discusses the epidemiology, clinical features, possible etiology and pathogenesis, diagnostic methods, malignant potential, treatment, and prognosis of Brunner's gland hamartoma.

Small Bowel Epithelial Precursor Lesions: A Focus on Molecular Alterations

The wider use of gastrointestinal endoscopic procedures has led to an increased detection of small intestinal preneoplastic and neoplastic epithelial lesions, most of which are identified in the duodenum and ampullary region. Like their malignant counterparts, small intestinal glandular precursor lesions, which include adenomas and hamartomas, may arise sporadically or be associated with hereditary tumor syndromes, such as familial adenomatous polyposis, MUTYH-associated polyposis, Lynch syndrome, Peutz-Jeghers syndrome, juvenile polyposis syndrome, and Cowden syndrome. In addition, dysplastic, preinvasive lesions have been observed adjacent to small bowel adenocarcinomas complicating immune-related disorders, such as celiac or Crohn’s disease. Adenomatous lesions may exhibit an intestinal-type, gastric-type, or, very rarely, serrated differentiation, related to different molecular pathogenetic mechanisms. Finally, in the background of multiple endocrine neoplasia 1 syndrome, precursor neuroendocrine growths have been described. In this review we offer a comprehensive description on the histo-molecular features of the main histotypes of small bowel epithelial precursors lesions, including: (i) sporadic adenomas (intestinal-type and gastric-type; non-ampullary and ampullary); (ii) syndromic adenomas; (iii) small bowel dysplasia in celiac and Crohn’s disease; (iv) serrated lesions; (v) hamartomatous lesions; and (vi) neuroendocrine precursor lesions.

The natural history of sporadic non‐ampullary duodenal epithelial tumors: Can we wait and see?

Objectives

Methods

Results

Conclusion

Expression of apoptosis repressor with caspase recruitment domain (ARC) in familial adenomatous polyposis (FAP) adenomas and its correlation with DNA mismatch repair proteins, p53, Bcl-2, COX-2 and beta-catenin

Background

Colorectal familial adenomatous polyposis (FAP) adenomas exhibit a uniform pathogenetic basis caused by a germline mutation in the adenomatous polyposis gene (APC), but the molecular changes leading to their development are incompletely understood. However, dysregulated apoptosis is known to substantially affect the development of colonic adenomas. One of the key regulatory proteins involved in apoptosis is apoptosis repressor with caspase recruitment domain (ARC).

Methods

The expression of nuclear and cytoplasmic ARC in 212 adenomas from 80 patients was analyzed by immunohistochemistry. We also compared expression levels of ARC with the expression levels of p53, Bcl-2, COX-2, and MMR proteins. Statistical analyses were performed by Spearman’s rank correlation and linear regression test.

Results

ARC was overexpressed in the nuclei and cytoplasm of most FAP adenomas investigated. Cytoplasmic ARC staining was moderately stronger (score 2) in 49.1% (n = 104/212) and substantially stronger (score 3) in 32.5% (n = 69/212) of adenomas compared to non-tumorous colorectal mucosa. In 18.4% (n = 39/212) of adenomas, cytoplasmic ARC staining was equivalent to that in non-tumorous mucosa.

Nuclear expression of ARC in over 75% of cells was present in 30.7% (n = 65/212) of investigated adenomas, and nuclear expression in 10–75% of cells was detected in 62.7% (n = 133/212). ARC expression in under 10% of nuclei was found in 6.6% (n = 14/212) of adenomas.

The correlation between nuclear ARC expression and cytoplasmic ARC expression was highly significant (p = 0.001). Moreover, nuclear ARC expression correlated positively with overexpression of Bcl-2, COX-2 p53 and β-catenin. Cytoplasmic ARC also correlated with overexpression of Bcl-2. Sporadic MMR deficiency was detected in very few FAP adenomas and showed no correlation with nuclear or cytoplasmic ARC.

Conclusions

Our results demonstrated that both cytoplasmic and nuclear ARC are overexpressed in FAP adenomas, thus in a homogenous collective. The highly significant correlation between nuclear ARC and nuclear β-catenin suggested that ARC might be regulated by β-catenin in FAP adenomas. Because of its further correlations with p53, Bcl-2, and COX-2, nuclear ARC might play a substantial role not only in carcinomas but also in precursor lesions.

The pathology of gastric and duodenal polyps: current concepts

The liberal use of upper endoscopy has led to an increased detection of gastric and duodenal polyps, which are identified in as many as 6 and 4.6% of patient examinations, respectively. Gastroduodenal polyps are a heterogeneous group of lesions that can be neoplastic or non-neoplastic (e.g. hyperplastic or heterotopical). Most polyps present characteristic topographical features, as well as endoscopic appearance and size. Evaluation of the surrounding mucosa is essential in assessing the underlying pathology (e.g. Helicobacter pylori, autoimmune gastritis or inherited polyposis syndromes). Phylogenetically, gastric and duodenal polyps can be classified according to the epithelial compartment from which they derive. Polyps that arise from the surface epithelium can either be of foveolar or intestinal type, and they can develop from either the native mucosa or the metaplastic epithelium (gastric intestinal metaplasia or duodenal foveolar metaplasia). Other polyps develop from the deeper glandular component, such as pyloric/oxyntic gland derived subtypes. In this review we focus upon epithelial polyps, with an emphasis on the most common and clinically relevant lesions, and present recently described entities.

Integrated genetic and epigenetic analysis of cancer-related genes in non-ampullary duodenal adenomas and intramucosal adenocarcinomas

The molecular and clinical characteristics of non‐ampullary duodenal adenomas and intramucosal adenocarcinomas are not fully understood because they are rare. To clarify these characteristics, we performed genetic and epigenetic analysis of cancer‐related genes in these lesions. One hundred and seven non‐ampullary duodenal adenomas and intramucosal adenocarcinomas, including 100 small intestinal‐type tumors (90 adenomas and 10 intramucosal adenocarcinomas) and 7 gastric‐type tumors (2 pyloric gland adenomas and 5 intramucosal adenocarcinomas), were investigated. Using bisulfite pyrosequencing, we assessed the methylation status of CpG island methylator phenotype (CIMP) markers and MLH1. Then using next‐generation sequencing, we performed targeted exome sequence analysis within 75 cancer‐related genes in 102 lesions. There were significant differences in the clinicopathological and molecular variables between small intestinal‐ and gastric‐type tumors, which suggests the presence of at least two separate carcinogenic pathways in non‐ampullary duodenal adenocarcinomas. The prevalence of CIMP‐positive lesions was higher in intramucosal adenocarcinomas than in adenomas. Thus, concurrent hypermethylation of multiple CpG islands is likely associated with development of non‐ampullary duodenal intramucosal adenocarcinomas. Mutation analysis showed that APC was the most frequently mutated gene in these lesions (56/102; 55%), followed by KRAS (13/102; 13%), LRP1B (10/102; 10%), GNAS (8/102; 8%), ERBB3 (7/102; 7%), and RNF43 (6/102; 6%). Additionally, the high prevalence of diffuse or focal nuclear β‐catenin accumulation (87/102; 85%) as well as mutations of WNT pathway components (60/102; 59%) indicates the importance of WNT signaling to the initiation of duodenal adenomas. The higher than previously reported frequency of APC gene mutations in small bowel adenocarcinomas as well as the difference in the APC mutation distributions between small intestinal‐type adenomas and intramucosal adenocarcinomas may indicate that the adenoma–carcinoma sequence has only limited involvement in duodenal carcinogenesis. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Management of ampullary adenomas in familial adenomatous polyposis syndrome: 16 years of experience from a tertiary cancer center

BACKGROUND AND AIMS

The management of ampullary adenomas in familial adenomatous polyposis (FAP) is challenging due to multiple adenomas in the duodenum, history of previous major abdominal surgery, and desmoid lesions. In this study, we aim to define the optimum management for ampullary adenomas, particularly in FAP.

METHODS

This is a retrospective study of all patients with pathology-confirmed ampullary adenomas in M.D. Anderson Cancer Center from 2002 to 2018. Relevant data were extracted, including patient demographics, treatments, outcomes, and adverse events.

RESULTS

There were 137 patients with ampullary adenomas who underwent 159 procedures; 95 of the 137 patients had FAP and were placed under close observation, 29 underwent endoscopic ampullectomy, 4 underwent surgical ampullectomy, and 31 underwent panreaticoduodenectomy (PD). In the close observation group, 12.6% progressed to advanced adenoma and subsequently underwent resection. There was no ampullary cancer detected in this group. The endoscopic ampullectomy group had a postprocedure adverse event rate of 10.2%. Eleven patients had residual/recurrent disease after endoscopic ampullectomy, 3 of whom needed surgery. Four patients underwent initial surgical ampullectomy and 2 subsequently needed PD. Patients who underwent PD had an adverse event rate of 29%. In this group, there were no cases of residual disease or recurrence.

CONCLUSIONS

The management of ampullary adenomas in FAP should be carefully considered for the best outcome. Although these patients can be managed by endoscopic ampullectomy, careful surveillance for recurrence should be followed along with prompt management of the recurrence when detected. Although PD provides a definitive treatment, it is limited by the patient's comorbid conditions and high adverse event rates.

Gastric and small intestinal traditional serrated adenomas: a detailed morphologic and immunohistochemical analysis

BACKGROUND/AIMS

Traditional serrated adenomas (TSAs), despite their low incidence in colorectum, may originate in other parts of the gastrointestinal (GI) tract, including stomach and small intestine. Malignant transformation for upper GI TSAs has recently been reported in the literature. Here, we present a series of gastric and small intestinal TSAs with the aim to characterize their morphologic and immunophenotypic features as well as their neoplastic potential in a compartmental manner using digitalized images.

MATERIALS AND METHODS

The study comprised 12 GI polyps with TSA features-5 gastric and 7 small intestinal. The extent of the characteristic features of TSA, including eosinophilic cells, ectopic crypt foci (ECF), slit-like serration, foveolar epithelium, goblet cells, together with dysplastic-carcinomatous foci were assessed on digitalized H-E images and were used as reference for immunohistochemical analysis.

RESULTS

All polyps in the cohort contained eosinophilic cells as the most extensive morphologic feature followed by ECF and slit-like serration in decreasing order. Serrated dysplasia was more common in gastric polyps, which more frequently showed neoplastic progression compared with the intestinal ones. CK20 was the most widely expressed marker with a preference to eosinophilic cells while ECFs were mostly negative. Ki67 showed the opposite pattern of CK20. MUC6 and MUC2 were selectively expressed in the basal zone and goblet cells, respectively.

CONCLUSION

Our results showed that the presence of eosinophilic cells with pencillate nuclei commonly accompanied by ECF and slit-like serration are the defining features of gastric and small intestinal TSAs. They frequently harbor neoplastic foci, particularly in gastric location where serrated dysplasia seems to be more common.

Prognostic relevance of programmed death-ligand 1 expression and microsatellite status in small bowel adenocarcinoma

Background: Small bowel adenocarcinoma (SBA) is a dreadful disease. Patient prognosis is limited due to late presentation and ineffective chemotherapy. PD-1/PD-L1 checkpoint immunotherapy is regarded as a promising approach in several cancer entities. The association of PD-1/PD-L1 expression and its impact on patient prognosis with SBA is unclear. Material and methods: Seventy-five consecutive patients who underwent surgery for SBA were retrospectively analyzed and stained for PD-L1 expression in the tumour or the stroma. Analysis of mismatch repair genes was performed to determine microsatellite status. Kaplan-Meier estimate was used to analyze patient survival. Univariate and multivariable Cox regression-analyses were used to assess the impact of PD-L1 expression and microsatellite status on patient survival.Results: PD-L1 was weakly upregulated within the tumour or the stroma and associated with prolonged survival (p = .0071 and p = .0472, respectively). Fifty-one tumours (68%) revealed microsatellite stability (MSS) and 24 tumours (32%) were microsatellite instable (MSI) without correlating with patient survival (p = .611). Neither PD-L1 expression in the tumour nor in the stroma was identified as an independent risk factor influencing survival (p = .572 and p = .3055).Conclusion: Although PD-L1 expression is associated with prolonged survival, it was not identified as an independent prognostic marker. Microsatellite status did not influence long-term survival.

Clinicopathological characteristics of non-ampullary duodenal tumors and their phenotypic classification

The tumorigenesis of non-ampullary duodenal epithelial tumors (NADETs) might be different between the oral and anal sides of Vater's papilla. We conducted an immunohistological review to elucidate the clinicopathological features according to the tumor location and phenotypic classification. A review of an institutional database identified 121 patients with 125 superficial NADETs. NADETs were histologically evaluated and classified into the intestinal or gastric type based on immunohistochemical analysis. Clinicopathological factors were compared based on the tumor location and phenotype. Logistic regression analysis was performed to identify independent predictors for gastric-type NADETs. According to location analysis, the mucin phenotype was significantly different (oral side, intestinal-type 64.8%, gastric-type 35.3%; anal side, intestinal-type 87.3%, gastric-type 12.7%; P < 0.01). Although the incidence of adenoma was significantly predominant in the intestinal type (75.3%), most gastric-type NADETs were cancerous (64.3%). Notably, most gastric-type NADETs were adenocarcinomas even when the tumor size was ≤0 mm. In multivariate analysis, tumor location on the oral side (odds ratio [OR], 4.42), villous structure (OR, 6.44), and low tumor gland density (OR, 9.49) were independent predictors of gastric-type tumors. Gastric-type NADETs significantly differ from intestinal-type NADETs in terms of tumor location, morphology, and biology.

Identification of marker genes and pathways specific to precancerous duodenal adenomas and early stage adenocarcinomas

BACKGROUND

The mechanism behind the pathogenesis and carcinogenesis of these neoplasms is not fully understood. The objective of this study was to identify genetic markers and pathways specific to precancerous duodenal adenomas and early stage adenocarcinomas through gene expression analysis.

METHODS

Gene expression profiling was performed in 4 pairs of duodenal adenoma/adenocarcinomas and corresponding matched normal tissue. Genes with consistent expression differences were identified and confirmed in 7 independent pairs. Gene set enrichment analysis (GSEA) was performed to characterize gene expression profiles of duodenal adenoma/adenocarcinomas, together with immunohistochemical staining of candidate oncogenic genes.

RESULTS

626 probes consistently demonstrated over a twofold expression difference between tumor-normal pairs. Reverse transcriptase polymerase chain reaction of genes with the most prominent difference in expression between tumors and normal mucosa (KLK7, KLK6, CEMIP, MMP7, KRT17, LGR5, G6PC, S100G, APOA1) validated the results of gene expression analysis. GSEA demonstrated a strong association between duodenal adenoma/adenocarcinomas with colorectal adenomas (p < 10^-5) and gene expression patterns seen after APC gene knockout (p < 10^-5), suggesting that the Wnt/β-catenin pathway plays a crucial role in the carcinogenesis of these neoplasms. Immunohistochemical staining of an independent group of duodenal adenomas confirmed over-accumulation of β-catenin in 80.0% (16/20).

CONCLUSIONS

Precancerous duodenal adenomas and early stage adenocarcinomas demonstrate gene expression characteristics with a strong resemblance to colorectal adenomas. The results of this study strongly suggest that upregulation of the Wnt/β-catenin pathway is the major factor involved in the initial stages of the carcinogenesis of duodenal adenocarcinomas.

Duodenal Epithelial Polyps: A Clinicopathologic Review

CONTEXT.—

Duodenal epithelial polyps are reported in 1.5% to 3% of individuals referred for upper endoscopy. Most duodenal epithelial polyps are asymptomatic and nonneoplastic; however, a small subset is neoplastic and may progress to adenocarcinoma. Recent advances in immunohistochemical and molecular techniques have helped further characterize these polyps, shedding light on their origin, classification, and risk of progression to adenocarcinoma.

OBJECTIVE.—

To provide a comprehensive clinicopathologic review of nonneoplastic and neoplastic duodenal epithelial polyps, with particular emphasis on recent developments in classification schemes and risk stratification based upon immunohistochemical and molecular profiles.

DATA SOURCES.—

This review is based on peer-reviewed literature and the authors' experiences.

CONCLUSIONS.—

In this review we provide an update on the clinicopathologic, immunohistochemical, and molecular features of duodenal epithelial polyps and discuss the surveillance recommendations and treatment options available. Particular attention should be placed on recognizing duodenal adenomas with intestinal, gastric, and serrated phenotype, as they have an increased risk of malignant transformation if not completely excised.

Burden and Profile of Somatic Mutation in Duodenal Adenomas from Patients with Familial Adenomatous- and MUTYH-associated Polyposis

Purpose: Duodenal polyposis and cancer are important causes of morbidity and mortality in familial adenomatous polyposis (FAP) and MUTYH-associated polyposis (MAP). This study aimed to comprehensively characterize somatic genetic changes in FAP and MAP duodenal adenomas to better understand duodenal tumorigenesis in these disorders.Experimental Design: Sixty-nine adenomas were biopsied during endoscopy in 16 FAP and 10 MAP patients with duodenal polyposis. Ten FAP and 10 MAP adenomas and matched blood DNA samples were exome sequenced, 42 further adenomas underwent targeted sequencing, and 47 were studied by array comparative genomic hybridization. Findings in FAP and MAP duodenal adenomas were compared with each other and to the reported mutational landscape in FAP and MAP colorectal adenomas.Results: MAP duodenal adenomas had significantly more protein-changing somatic mutations (P = 0.018), truncating mutations (P = 0.006), and copy number variants (P = 0.005) than FAP duodenal adenomas, even though MAP patients had lower Spigelman stage duodenal polyposis. Fifteen genes were significantly recurrently mutated. Targeted sequencing of APC, KRAS, PTCHD2, and PLCL1 identified further mutations in each of these genes in additional duodenal adenomas. In contrast to MAP and FAP colorectal adenomas, neither exome nor targeted sequencing identified WTX mutations (P = 0.0017).Conclusions: The mutational landscapes in FAP and MAP duodenal adenomas overlapped with, but had significant differences to those reported in colorectal adenomas. The significantly higher burden of somatic mutations in MAP than FAP duodenal adenomas despite lower Spigelman stage disease could increase cancer risk in the context of apparently less severe benign disease. Clin Cancer Res; 23(21); 6721-32. ©2017 AACR.

Clinical features of upper gastrointestinal serrated lesions: An endoscopy database analysis of 98746 patients

AIM

To analyse the clinical features of patients with the serrated lesions in the upper gastrointestinal tract (UPGI) tract.

METHODS

Patients who underwent routine esophagogastroduodenoscopy (EGD) at the Digestive Endoscopy Centre of General Hospital, Tianjin Medical University between January 2011 and December 2015 were consecutively recruited. Patients with UPGI serrated lesions were consecutively identified. The patients’ demographics and histopathology were recorded. The colorectal findings for patients who underwent colonoscopy simultaneously or within six months were also extracted from the colonoscopy database. In addition, we analysed differences in colorectal neoplasia detection between the study patients and randomly selected patients matched for age and gender who did not exhibit serrated lesions and who also underwent colonoscopy in the same period.

RESULTS

A total of 21 patients out of 98746 patients (0.02%) who underwent EGD were confirmed to have serrated lesions with predominantly crenated, sawtooth-like configurations. The mean age of the 21 patients was (55.3 ± 17.2) years, and 11 patients were male (52.4%). In terms of the locations of the serrated lesions, 17 were found in the stomach (including 3 in the cardia, 9 in the corpus and 5 in the antrum), 3 were found in the duodenum, and 1 was found in the esophagus. Serrated lesions were found in different mucosal lesions, with 14 lesions were detected in polyps (8 hyperplastic polyps and 6 serrated adenomas with low grade dysplasia), 3 detected in Ménétrier gastropathy, 3 detected in an area of inflammation or ulcer, and 1 detected in the intramucosal carcinoma of the duodenum. In addition, colonoscopy data were available for 18 patients, and a significantly higher colorectal adenoma detection rate was observed in the UPGI serrated lesions group than in the randomly selected age- and gender-matched group without serrated lesions who also underwent colonoscopy in the same period (38.9% vs 11.1%, OR = 5.091, 95%CI: 1.534-16.890, P = 0.010). The detection rate of advanced adenoma was also higher in the UPGI serrated lesions group (22.2% vs 4.2%, OR = 6.571, 95%CI: 1.322-32.660, P = 0.028).

CONCLUSION

Serrated lesions in the UPGI were detected in various mucosal lesions with different pathological morphologies. Moreover colonoscopy is recommended for the detection of concurrent colorectal adenoma for these patients.

Nonampullary duodenal adenoma: Current understanding of its diagnosis, pathogenesis, and clinical management

Nonampullary duodenal adenomas are relatively common in familial adenomatous polyposis (FAP), but nonampullary sporadic duodenal adenomas (SDAs) are rare. Emerging evidence shows that duodenal adenomas, regardless of their anatomic location and whether they are sporadic or FAP-related, share morphologic and molecular features with colorectal adenomas. The available data suggest that duodenal adenomas develop to duodenal adenocarcinomas via similar mechanisms. The optimal approach for management of duodenal adenomas remains to be determined. The techniques for endoscopic resection of duodenal adenoma include snare polypectomy, endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), and argon plasma coagulation ablation. EMR may facilitate removal of large duodenal polyps. Although several studies have reported cases of successful ESD for duodenal adenomas, the procedure is technically difficult to perform safely because of the anatomical properties of the duodenum. Although current clinical practice recommends endoscopic resection of all large duodenal adenomas in patients with FAP, endoscopic treatment is usually insufficient to guarantee a polyp-free duodenum. Surgery is indicated for FAP patients with severe polyposis or nonampullary SDAs or FAP-related polyps not amenable to endoscopic resection. Further studies are needed to develop newer endoscopic techniques to guide diagnostic and therapeutic decisions for future management of nonampullary duodenal adenomas.

Do serrated neoplasms of the small intestine represent a distinct entity? Pathological findings and molecular alterations in a series of 13 cases

AIMS

To characterize pathological, immunohistochemical and molecular features of small intestinal serrated neoplasms.

METHODS AND RESULTS

We report 13 serrated neoplasms located predominantly in the duodenum (median age, 71 years; male to female ratio, 7:6). The serrated adenomas demonstrated prominent serration, ectopic crypt formations and cytological features reminiscent of colorectal traditional serrated adenomas. Almost half the serrated adenomas demonstrated high-grade dysplasia or were associated with an adenocarcinoma. Immunohistochemical and molecular analysis showed an intestinal (CDX2-positive) phenotype in all tumours, abnormal β-catenin staining in three cases (23%), abnormal p53 expression in four cases (31%), focal loss of MGMT expression in one case (8%), KRAS mutation in five cases (38%) and CpG island methylator phenotype in six cases (50%). A diffuse pattern of Ki67 expression was present in eight adenomas (62%) and was associated with high-grade dysplasia (P = 0.02). No BRAF(V600E) mutation or loss of MLH1 expression was observed.

CONCLUSIONS

To our knowledge, this is the first series reporting serrated adenoma in the small intestine, a rare subtype of adenomas resembling traditional serrated adenoma with aggressive morphological features. The absence of the BRAF(V600E) mutation does not support a role for the serrated neoplasia pathway in the development of these lesions, as in colorectal serrated polyps.

Intraductal dissemination of papillary adenocarcinoma of the ampulla of Vater in the pancreatic duct

It has been speculated that intraductal dissemination, via the pancreatic duct, bile duct, or mammary duct, is a unique form of cancer cell spread. However, clinical evidence to confirm this form of dissemination has been lacking. Here we report a case of papillary adenocarcinoma of the ampulla of Vater in which retrograde dissemination to the pancreatic duct was strongly suggested. A 79-year-old woman underwent pancreatoduodenectomy for a 22 mm microinvasive papillary adenocarcinoma of the ampulla. Multiple carcinomas in situ were found in the pancreatic duct distant from the ampulla. Seven months later, she underwent a second operation for a recurrent papillary adenocarcinoma at the pancreato-jejunal anastomosis showing exophytic and expansive growth into the jejunal lumen that connected to an intraductal adenocarcinoma in the pancreatic body. None of these tumors showed invasive growth, or vascular or neural invasion, being separate from each other but sharing identical histological, immunohistochemical, and molecular features; papillary growth, a pancreatobiliary phenotype, the same pattern of genomic loss of heterozygosity, and no mutation of the KRAS, TP53, and GNAS genes. These results imply that this papillary adenocarcinoma of the ampulla of Vater had disseminated to the pancreatic duct in a retrograde manner and recurred in the remnant pancreas.

CpG island methylator phenotype and its association with malignancy in sporadic duodenal adenomas

CpG island methylator phenotype (CIMP) has been found in multiple precancerous and cancerous lesions, including colorectal adenomas, colorectal cancers, and duodenal adenocarcinomas. There are no reports in the literature of a relationship between CIMP status and clinicopathologic features of sporadic duodenal adenomas. This study sought to elucidate the role of methylation in duodenal adenomas and correlate it with KRAS and BRAF mutations. CIMP+ (with more than 2 markers methylated) was seen in 33.3% of duodenal adenomas; 61% of these CIMP+ adenomas were CIMP-high (with more than 3 markers methylated). Furthermore, CIMP+ status significantly correlated with older age of patients, larger size and villous type of tumor, coexistent dysplasia and periampullary location. MLH1 methylation was seen in 11.1% of duodenal adenomas and was significantly associated with CIMP+ tumors, while p16 methylation was an infrequent event. KRAS mutations were frequent and seen in 26.3% of adenomas; however, no BRAF mutations were detected. Furthermore, CIMP-high status was associated with larger size and villous type of tumor and race (non-white). These results suggest that CIMP+ duodenal adenomas may have a higher risk for developing malignancy and may require more aggressive management and surveillance.

Frequent GNAS and KRAS mutations in pyloric gland adenoma of the stomach and duodenum

Gastric and duodenal adenomas exhibit a significant morphological and phenotypical diversity and are classified into intestinal-type, foveolar-type and pyloric gland adenomas. We analysed the mutations in GNAS, KRAS, BRAF and CTNNB1 and the expressions of mismatch repair (MMR) proteins in 80 gastric and 32 duodenal adenomas with histologically distinct subtypes, as well as in 71 gastric adenocarcinomas. Activating GNAS mutations were found in 22 of the 35 pyloric gland adenomas (PGAs; 63%) but in none of the foveolar-type or intestinal-type adenomas or the adenocarcinomas. Fourteen PGAs (41%), two foveolar-type adenomas (9%), five intestinal-type adenomas (9%) and one adenocarcinoma (1%) had KRAS mutations. BRAF mutations were absent in all the adenomas and adenocarcinomas that were examined. CTNNB1 mutations were only found in two intestinal-type adenomas (4%). Notably, 13 of the 14 KRAS-mutated gastric and duodenal PGAs had concurrent GNAS mutations. The loss of the MMR proteins, which is indicative of microsatellite instability, was observed in one PGA (3%), 12 foveolar-type adenomas (52%), one intestinal-type adenoma (2%) and five adenocarcinomas (7%). These observations indicate that each histological subtype of gastric and duodenal adenomas has a distinct genetic background. In particular, the present study identified the frequent presence of activating GNAS mutations, which are often associated with KRAS mutations, as a characteristic genetic feature of PGAs of the stomach and duodenum.

Phenotypic and genotypic characterization of carcinomas of the papilla of Vater has prognostic and putative therapeutic implications

We further characterize the heterogeneous carcinomas of the papilla of Vater (CPVs) in relation to various clinicopathologic patient characteristics and patient survival. Of the 71 reevaluated CPVs, 32 were intestinal, 26 were pancreatobiliary, 6 were mixed, 4 were mucinous, and 3 were poorly differentiated carcinomas. The prevalence of cytokeratin 20 and cytokeratin 7 correlated with the intestinal (25/32 [78%] vs 13/32 [41%]) and pancreatobiliary (6/26 [23%] vs 24/26 [92%]) phenotypes. CDX2 was found in mucinous (3/4 [75%]), intestinal (7/32 [22%]), and some mixed (1/6 [1%]) CPVs. A KRAS mutation was detected in all poorly differentiated CPVs and in about 20% of each of the other types. In multivariate analyses, tumor type, local tumor spread, and lymph node metastases were independent prognostic factors of patient survival. We provide further evidence of the prognostic relevance of the phenotypic and genotypic diversity of CPVs. Besides the poorly differentiated CPV, the most common KRAS wild type makes them a putative target for an anti-epidermal growth factor receptor therapy.