Small bowel adenocarcinomas--existing evidence and evolving paradigms

Genomic landscape and clinical impact of homologous recombination repair gene mutation in small bowel adenocarcinoma

BACKGROUND

Small bowel adenocarcinoma (SBA) is a rare malignancy with a poor prognosis and limited treatment options. Although homologous recombination deficiency has been studied as a biomarker for other cancer types, the clinical and genomic implications of homologous recombination repair (HRR) gene mutations in SBA remain unclear.

METHODS

We retrospectively analyzed the data of 628 patients with advanced or recurrent SBA from a nationwide genomic database. Patients were categorized into HRR mutation and non-HRR mutation groups and compared for their clinical and genomic characteristics including tumor mutational burden (TMB) and microsatellite instability-high (MSI-H) were compared. Treatment efficacy and overall survival (OS) were assessed based on HRR gene mutation status and primary tumor site (duodenal adenocarcinoma [DA] vs. small intestinal carcinoma [SIC]).

RESULTS

Patients with the HRR mutations had higher frequencies of TMB and MSI-H than those without the mutation (P < 0.0001). In DA, HRR gene mutation positivity was associated with improved OS and higher overall response rates (ORR) to platinum-based chemotherapy (OS: not reached vs. 23.5 months, P = 0.040; ORR: 33 % vs. 19 %, P = 0.046), whereas no significant associations were observed with SIC.

CONCLUSION

HRR gene mutation may be a potential biomarker for platinum-based chemotherapy efficacy in SBA, especially in DA, highlighting the need for site-specific therapies.

Imaging of the Small Bowel Tumors

Small bowel tumors are rare gastrointestinal tumors. Neuroendocrine tumors are the most common and demonstrate unique subtypes depending on their location. Adenocarcinomas are most common in the duodenum demonstrating luminal narrowing and irregularity. Gastrointestinal stromal tumors are heterogeneously enhancing lesions with endophytic and/or exophytic growth patterns. Immunotherapy is a unique treatment of these tumors with tumoral response best assessed with both routine computed tomography (CT) and PET/CT. Primary small bowel lymphoma has many imaging patterns, most commonly being aneurysmal dilation and thickening of the small bowel. Metastases are common and may present as polypoid lesions, focal wall thickening, or serosal deposits.

Intestinal obstruction caused by early stage primary ileum adenocarcinoma: A case report and review of literature

BACKGROUND

Ileum adenocarcinoma (IA), a type of small bowel adenocarcinoma, is a rather uncommon factor associated with obstruction in small bowel. Owing to its location and indefinite clinical symptoms, the diagnosis of IA is difficult, and survival is usually poor. With respect to the rarity of this disease, very few studies have reported such cases to provide a reference for treatment.

CASE SUMMARY

In this manuscript, a case of a 48-year-old man presented with chronic right lower abdominal pain and distention, queasiness and emesis. A computed tomography scan revealed intestinal wall thickening and an intestinal obstruction in the terminal ileum. He was diagnosed with inflammatory bowel disease. However, his symptoms were not relieved after conservative treatment. The patient subsequently underwent exploratory laparotomy, and a tumour in the ileum measuring approximately 2.0 cm × 2.0 cm that was located 20 cm from the ileocolic valve was discovered incidentally and was operatively resected along with the enlarged lymph nodes. Pathological examination revealed a stage IIA (T3N0M0) ulcerative IA. Along with imaging examinations, a diagnosis of primary IA with no lymph or distant metastases was considered. The patient was discharged and recovered well as of the writing of this manuscript.

CONCLUSION

IA should be considered as a differential diagnosis in cases of intestinal obstruction, and the recommended method for local disease treatment is surgery.

Molecularly redefining small bowel adenocarcinoma to accelerate precision patient care - protocol of a multicenter observational cohort biomarker study

BACKGROUND

Small Bowel Adenocarcinoma (SBA) is a rare gastrointestinal cancer with a limited understanding of the molecular pathology. This study aims to bridge the knowledge gap, providing a robust molecular foundation for SBA and addressing the clinical challenges inherent in treating this orphan disease. The study proposes to redefine the clinical management for SBA patients through advanced molecular profiling techniques to improve potential precision medicine.

METHODS/DESIGN

This National multicenter, observational cohort study combines retrospective and prospective analyses across Danish University Hospitals. The study enrolls patients diagnosed with SBA, retrospectively from 2009 and prospectively from 2022 onwards. Molecular profiling, including DNA, RNA, and T-cell receptor sequencing, will be conducted on SBA tissue samples. The primary outcome is to categorize SBA into consensus molecular-guided subgroups. Secondary outcomes include correlating these subgroups with clinical features, treatment responses, and patient outcomes. Machine learning algorithms will be employed for bioinformatic analyses to interpret molecular data. Ethical approval has been obtained, and patient consent will be secured for the retrospective study component.

DISCUSSION

The molecular and clinical characterization of SBA is expected to add novel insights into the heterogeneity of this rare disease. By identifying molecular subgroups, the research could enable the development of personalized treatment strategies, a paradigm shift within SBA. The study acknowledges the challenges of working with orphan diseases, including limited patient numbers and diverse clinical presentations. However, its findings will have the potential to substantially impact future clinical practices and guide targeted therapies for SBA patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06234306.

Small bowel neuroendocrine tumors: Unique features and low lethality compared with small bowel adenocarcinoma

BACKGROUND AND AIM

Population-based studies comparing clinical characteristics and survival disparities between patients with small bowel adenocarcinoma (SBA) and small bowel neuroendocrine tumors (SBNETs) in the United States are limited.

METHODS

Data for patients with SBA or SBNETs, obtained from the Surveillance, Epidemiology, and End Results database for the years between 2000 and 2018 were analyzed.

RESULTS

Between 2000 and 2018, the age-adjusted incidence of SBA experienced a marginal increase whereas SBNETs demonstrated a significant increase, emerging as the predominant subtype of small bowel cancer (SBC). Diagnoses peaked at ages 65-69 years for SBA and 60-64 years for SBNETs, with the latter exhibiting a heightened age-specific incidence and maintaining equilibrium in gender distribution. Clinicopathologic disparities revealed SBA's duodenal predilection, larger tumor size, and advanced stages, contrasting with SBNETs' ileal predilection, early-stage presentation, and superior outcomes. SBNETs patients underwent surgery more frequently but received less chemotherapy and radiation than SBA patients. Factors intricately correlated with a diagnosis of SBNETs included female gender, White race, advanced age, marital status, recent diagnoses, superior tumor differentiation, smaller size, distal location, and early-stage presentation. Survival analysis unveiled a remarkable 79% reduction in the mortality risk for SBNETs compared with SBA. Subgroup analysis further confirmed the consistently favorable survival advantages of SBNETs, highlighting the clinical relevance of histological classification in prognostication.

CONCLUSION

Compared with SBA, SBNETs exhibited distinctive clinicopathological features characterized by a higher inclination toward low-grade and early-stage manifestations, thereby contributing to superior survival outcomes.

The application of the combination between artificial intelligence and endoscopy in gastrointestinal tumors

Gastrointestinal (GI) tumors have always been a major type of malignant tumor and a leading cause of tumor‐related deaths worldwide. The main principles of modern medicine for GI tumors are early prevention, early diagnosis, and early treatment, with early diagnosis being the most effective measure. Endoscopy, due to its ability to visualize lesions, has been one of the primary modalities for screening, diagnosing, and treating GI tumors. However, a qualified endoscopist often requires long training and extensive experience, which to some extent limits the wider use of endoscopy. With advances in data science, artificial intelligence (AI) has brought a new development direction for the endoscopy of GI tumors. AI can quickly process large quantities of data and images and improve diagnostic accuracy with some training, greatly reducing the workload of endoscopists and assisting them in early diagnosis. Therefore, this review focuses on the combined application of endoscopy and AI in GI tumors in recent years, describing the latest research progress on the main types of tumors and their performance in clinical trials, the application of multimodal AI in endoscopy, the development of endoscopy, and the potential applications of AI within it, with the aim of providing a reference for subsequent research.

Adenocarcinoma in the Jejunum Presenting as Acute Abdomen and Melena in an Otherwise Healthy Patient: A Case Report

A jejunal adenocarcinoma is a rare form of cancer that is difficult to diagnose due to its vague and non-specific symptoms, often leading to delayed treatment and poor outcomes. In this case, we report a 43-year-old male who presented with acute abdominal pain, weight loss, and melena. A CT scan revealed a mass in the small intestine, and subsequent exploratory laparotomy confirmed the presence of a tumor, which was surgically excised. Histopathological analysis confirmed jejunal adenocarcinoma with positive CDX2 staining, ruling out other adenocarcinoma subtypes. This case underscores the importance of including jejunal adenocarcinoma in differential diagnoses of acute abdomen and highlights the critical role of early surgical intervention in improving patient outcomes.

Bibliometrics analysis on the research status and trends of small bowel adenocarcinoma: 1923-2023

Objectives

The aim of this research is to discuss the research status, hotspots, frontiers, and development trends in the field of small bowel adenocarcinoma based on bibliometrics and visual analysis by CiteSpace software.

Methods

The relevant research articles on SBA from 1923 to 2023 were retrieved from the Web of Science Core Collection database. CiteSpace software was used to form a visual knowledge map and conduct analysis for the countries/regions, journals, authors, keywords, clusters, research hotspots and frontiers of the included articles.

Results

There were 921 articles included, and the number of articles published during 1923-2023 is increasing. The country with the highest number of articles published was the United States (443, 38.76%), followed by Japan (84, 9.12%) and France (72, 7.82%). The author with the highest number of publications is Ansell, Overman MJ (33, 3.58%), and the author with the highest co-citation frequency is Overman MJ (218). Journal of Clinical Oncology is the journal with the highest publication frequency. The top five cluster groups were "chemotherapy", "inflammatory bowel disease", "celiac disease", "tumor" and "small intestine". The related disease, chemotherapy drugs, and treatment regimens of SBA form the main research fields, and prognosis and diagnosis are the research hotspots and trends.

Conclusion

The global research field in SBA has expanded in the past 100 years. The prognosis and new diagnosis of SBA are hotspots in this field and require further study in the future.

Genomic Profiling of Small Intestine Cancers From a Real-World Data Set Identifies Subgroups With Actionable Alterations

PURPOSE

Panel-based comprehensive genomic profiling (CGP) is used in clinical practice worldwide; however, large real-world data (RWD) of patients with advanced small intestine cancer have not been characterized. We investigated differences in the prevalence of clinically relevant alterations across molecularly defined or age-stratified subgroups.

PATIENTS AND METHODS

This was a collaborative biomarker study of RWD from CGP testing (Foundation Medicine, Inc). Hybrid capture was conducted on at least 324 cancer-related genes and select introns from up to 31 genes frequently rearranged in cancer. Overall, 1,364 patients with advanced small intestine cancer were available for analyses and were stratified by age (≥40 years/<40 years), microsatellite instability (MSI) status, tumor mutational burden (TMB) status (high ≥10/low <10 Muts/Mb), and select gene alterations. The frequency of alterations was analyzed using a chi-square test with Yate's correction.

RESULTS

Genes with frequent alterations included TP53 (59.8%), KRAS (54.8%), APC (27.7%), and CDKN2A (22.4%). Frequent genes with amplifications were MYC (6.7%), MDM2 (5.9%), GATA6 (5.5%), and CCND1 (3.4%). Patients younger than 40 years had significantly lower frequency of APC mutations than those 40 years and older (10.4% v 28.7%; P = .0008). Druggable genomic alterations were detected in 22.3% of patients: BRAF V600E (1.2%), BRCA1 (1.8%), BRCA2 (3.2%), ERBB2 amplification (3.2%), KRAS G12C (3.3%), NTRK1/2/3 fusion (0.07%), MSI-high (7.0%), and TMB-high (12.2%), with no significant differences in the frequency according to age (<40 years v ≥40 years; 22.1% v 22.3%). TMB of 10-20 Mut/Mb was observed in 4.8% of patients, and TMB ≥20 Mut/Mb was seen in 7.3% of the cohort.

CONCLUSION

RWD from clinical panel testing revealed the genomic landscape in small intestine cancer by subgroup. These findings provide insights for the future development of treatments in advanced small intestine cancer.

Development and validation of a nomogram for predicting cancer-specific survival in small-bowel adenocarcinoma patients using the SEER database

BACKGROUND

Small bowel adenocarcinoma (SBA) is a rare gastrointestinal malignancy forwhich survival is hampered by late diagnosis, complex responses to treatment, and poor prognosis. Accurate prognostic tools are crucial for optimizing treatment strategies and improving patient outcomes. This study aimed to develop and validate a nomogram based on the Surveillance, Epidemiology, and End Results (SEER) database to predict cancer-specific survival (CSS) in patients with SBA and compare it to traditional American Joint Committee on Cancer (AJCC) staging.

METHODS

We analyzed data from 2,064 patients diagnosed with SBA between 2010 and 2020 from the SEER database. Patients were randomly assigned to training and validation cohorts (7:3 ratio). Kaplan‒Meier survival analysis, Cox multivariate regression, and nomograms were constructed for analysis of 3-year and 5-year CSS. The performance of the nomograms was evaluated using Harrell's concordance index (C-index), the area under the receiver operating characteristic (ROC) curve, calibration curves, decision curve analysis (DCA), net reclassification improvement (NRI), and integrated discrimination improvement (IDI).

RESULTS

Multivariate Cox regression identified sex, age at diagnosis, marital status, tumor site, pathological grade, T stage, N stage, M stage, surgery, retrieval of regional lymph nodes (RORLN), and chemotherapy as independent covariates associated with CSS. In both the training and validation cohorts, the developed nomograms demonstrated superior performance to that of the AJCC staging system, with C-indices of 0.764 and 0.759, respectively. The area under the curve (AUC) values obtained by ROC analysis for 3-year and 5-year CSS prediction significantly surpassed those of the AJCC model. The nomograms were validated using calibration and decision curves, confirming their clinical utility and superior predictive accuracy. The NRI and IDI indicated the enhanced predictive capability of the nomogram model.

CONCLUSION

The SEER-based nomogram offers a significantly superior ability to predict CSS in SBA patients, supporting its potential application in clinical decision-making and personalized approaches to managing SBA to improve survival outcomes.

Synchronous Multiple Primary Malignant Adenocarcinoma of the Descending Colon and Fungating Bleeding Adenocarcinoma of the Terminal Ileum Presenting Massive Rectal Bleeding: A Trap for the Unwary

Primary cancer of the ileum is rare, and when it occurs in conjunction with primary colon cancer, it becomes even more infrequent and challenging to diagnose prior to surgical intervention. Primary small bowel cancers can be overlooked and may be misidentified as small bowel mesenchymal tumours or advanced metastases from colon cancer. We present an exceedingly uncommon case of ruptured primary ileal cancer combined with primary descending colon cancer presenting with gastrointestinal bleeding. Based on our understanding, instances of dual tumours concurrently occurring are exceedingly infrequent. In this patient, there was a preoperative suspicion of bleeding from colon cancer in the descending region. However, intraoperative exploration revealed that the location of the bleeding was a terminal ileal mass. Following the surgical intervention, the patient recovered satisfactorily. Intraoperative exploration of the entire gastrointestinal tract is therefore necessary in patients with gastrointestinal haemorrhage, especially in those who require urgent surgery without adequate preoperative investigations. If a mass is detected at the end of the ileum, intraoperative pathology should be performed if feasible. Subsequently, if the diagnosis reveals an adenocarcinoma, terminal ileocolic resection and right hemicolectomy are necessary for appropriate resection.

Clinical features and prognosis of malignant small bowel tumors: Experience from a university hospital in Chile

BACKGROUND

Small bowel tumors (SBT) are infrequent and represent a small proportion of digestive neoplasms. There is scarce information about SBT in Latin America.

AIM

To describe the epidemiology, clinical characteristics, diagnostic methods, and survival of malignant SBTs.

METHODS

Retrospective observational study of adult patients with histopathological diagnosis of SBT between 2007 and 2021 in a university hospital in Chile.

RESULTS

A total of 104 patients [51.9% men; mean age 57 years] with SBT. Histological type: neuroendocrine tumor (NET) (43.7%, n=38), gastrointestinal stromal tumors (GIST) (21.8%, n=19), lymphoma (17.2%, n=15) and adenocarcinoma (AC) (11.5%, n=10). GIST was more frequent in duodenum (50%; n=12) and NET in the ileum (65.8%; n=25). Metastasis was observed in 17 cases, most commonly from colon and melanoma. Nausea and vomiting were significantly more often observed in AC (p=0.035), as well as gastrointestinal bleeding in GIST (p=0.007). The most common diagnostic tools were CT and CT enteroclysis with an elevated diagnostic yield (86% and 94% respectively). The 5-year survival of GIST, NET, lymphoma and AC were 94.7% (95%CI: 68.1-99.2), 82.2% (95%CI: 57.6-93.3), 40.0% (95%CI: 16.5-82.8) and 25.9% (95%CI: 4.5-55.7%), respectively. NET (HR 6.1; 95%CI: 2.1-17.2) and GIST (HR 24.4; 95%CI: 3.0-19.8) were independently associated with higher survival compared to AC, adjusted for age and sex.

CONCLUSIONS

Malignant SBT are rare conditions and NETs are the most common histological subtype. Clinical presentation at diagnosis, location or complications may suggest a more probable diagnosis. GIST and NET are associated with better survival compared to other malignant subtypes.

Clinicopathological features and prognosis of primary small bowel adenocarcinoma: a large multicenter analysis of the JSCCR database in Japan

BACKGROUND

The clinicopathological features and prognosis of primary small bowel adenocarcinoma (PSBA), excluding duodenal cancer, remain undetermined due to its rarity in Japan.

METHODS

We analyzed 354 patients with 358 PSBAs, between January 2008 and December 2017, at 44 institutions affiliated with the Japanese Society for Cancer of the Colon and Rectum.

RESULTS

The median age was 67 years (218 males, 61.6%). The average tumor size was 49.9 (7-100) mm. PSBA sites consisted of jejunum (66.2%) and ileum (30.4%). A total of 219 patients (61.9%) underwent diagnostic small bowel endoscopy, including single-balloon endoscopy, double-balloon endoscopy, and capsule endoscopy before treatment. Nineteen patients (5.4%) had Lynch syndrome, and 272 patients (76.8%) had symptoms at the initial diagnosis. The rates for stages 0, I, II, III, and IV were 5.4%, 2.5%, 27.1%, 26.0%, and 35.6%, respectively. The 5-year overall survival rates at each stage were 92.3%, 60.0%, 75.9%, 61.4%, and 25.5%, respectively, and the 5-year disease-specific survival (DSS) rates were 100%, 75.0%, 84.1%, 59.3%, and 25.6%, respectively. Patients with the PSBA located in the jejunum, with symptoms at the initial diagnosis or advanced clinical stage had a worse prognosis. However, multivariate analysis using Cox-hazard model revealed that clinical stage was the only significant predictor of DSS for patients with PSBA.

CONCLUSIONS

Of the patients with PSBA, 76.8% had symptoms at the initial diagnosis, which were often detected at an advanced stage. Detection during the early stages of PSBA is important to ensure a good prognosis.

Current Perspectives on Small Bowel Tumors: Overview of Prevalence, Clinical Manifestations, and Treatment Approaches

Small bowel tumors (SBTs) constitute a rare yet increasingly recognized group of gastrointestinal neoplasms, accounting for less than 5% of all gastrointestinal cancers. Despite their infrequency, the incidence of SBTs has exhibited a notable upward trend, underscoring the importance of understanding these diverse and complex tumors. This review consolidates current knowledge on SBTs, encompassing epidemiology, risk factors, clinical manifestations, diagnostic advancements, and treatment modalities. Data from various sources are analyzed to present a comprehensive overview of the evolving landscape of SBTs. Our findings indicate that adenocarcinomas, carcinoid tumors, lymphomas, and gastrointestinal stromal tumors (GISTs) are the common SBTs. While adenocarcinoma and neuroendocrine tumors are the common types of SBTs in the West, GIST and lymphoma are more common in Asia. Common risk factors include genetic syndromes and inflammatory bowel diseases. There is variability in clinical presentations depending on the type of tumors. Although diagnostic challenges persist, advancements in imaging and endoscopic techniques have improved detection rates. Treatment strategies are evolving; surgical resection remains the mainstay for localized disease, augmented by systemic therapies and targeted agents for advanced stages. This review emphasizes the importance of early detection and individualized treatment approaches in improving outcomes for SBT patients. It addresses the need for ongoing research and innovation in managing these tumors.

Immunotherapy in small bowel adenocarcinoma: a potential role?

Small bowel adenocarcinoma (SBA) is a rare tumor with an unfavorable prognosis, and due to its rarity, few studies on its treatment are available. Chemotherapy remains the standard of treatment in advanced disease. Recently immunotherapy has demonstrated to be a valid therapeutic option for many solid tumors. We reviewed the data published in literature to understand the impact of immunotherapy in this cancer.

Outcomes of Metastatic and Unresectable Small Bowel Adenocarcinoma in Japan According to the Treatment Strategy: A Nationwide Observational Study

PURPOSE

Limited information is available regarding the characteristics and outcomes of stage IV small bowel adenocarcinoma (SBA) in Japan. This study examined the clinical and pathological characteristics and outcomes according to the treatment strategies in patients with stage IV SBA.

METHODS

This retrospective observational study used the data of patients with jejunal or ileal adenocarcinoma collected by the Small Bowel Malignant Tumor Project of the Japanese Society for Cancer of the Colon and Rectum. Descriptive statistics were expressed as the mean (standard deviation) or median (range). Survival analysis was performed using Kaplan-Meier curves and pairwise log-rank tests.

RESULTS

Data from 128 patients were analyzed. The treatment strategies were chemotherapy alone (26 of 128, 20.3%), surgery alone (including palliative surgery; 21 of 128, 16.4%), surgery + chemotherapy (74 of 128, 57.8%), and best supportive care (7 of 128, 5.5%). The median (range) overall survival was 16 (0-125) months overall, and 11 (1-38) months, 8 (0-80) months, 18 (0-125) months, and 0 (0-1) months for the chemotherapy, surgery, surgery + chemotherapy, and best supportive care groups, respectively. Three main categories of chemotherapeutic regimen were used: a combination of fluoropyrimidine and oxaliplatin (F + Ox), fluoropyrimidine and irinotecan (F + Iri), and single-agent fluoropyrimidine. Among patients treated with chemotherapy, the median (range) OS was 16 (1-106) months overall, and 17 (1-87) months, 29 (7-39) months, and 16 (1-106) months in patients treated with fluoropyrimidine, F + Iri, and F + Ox, respectively.

CONCLUSION

Patients treated with surgery, chemotherapy, or both had a better prognosis than those who received best supportive care. Among patients who received chemotherapy, survival did not differ according to the chemotherapeutic regimen.

Comprehensive genomic profiling of small bowel adenocarcinoma by tissue and plasma biopsy

Small bowel adenocarcinoma (SBA) is a rare and aggressive malignancy with limited treatment options and poor prognosis. The molecular landscape and immunological characteristics of SBA are poorly understood. Here, we performed comprehensive mutation profiling of tissue and plasma biopsies from 143 and 42 patients with SBA. Analysis showed that SBA had a distinct mutation spectrum from left- and right-sided colorectal carcinoma. Plasma biopsy had high concordance with tissue biopsy for single nucleotide variants and structural variants, but low concordance for copy number variations, which showed that plasma biopsy can be an alternative to tissue biopsy. Moreover, we analyzed the association of TMB with clinical and molecular features, and found that TMB was significantly higher in tumors with DNA damage response alterations. Our findings provide valuable insights into the molecular and immunological features of SBA and demonstrate the potential of plasma biopsy as a non-invasive method for SBA diagnosis and treatment.

Small Bowel Carcinoma in the Setting of Inflammatory Bowel Disease

Small bowel carcinomas are rare in the general population, but the incidence is increasing. Patients with inflammatory bowel diseases (IBDs) are at significantly higher risk of small bowel adenocarcinomas than their non-IBD counterparts, with Crohn's patients having at least a 12-fold increased risk and ulcerative colitis patients with a more controversial and modest 2-fold increased risk compared with the general population. IBD patients with small bowel carcinomas present with nonspecific symptoms that overlap with typical IBD symptoms, and this results in difficulty making a preoperative diagnosis. Cross-sectional imaging is rarely diagnostic, and most cancers are found incidentally at the time of surgery performed for an IBD indication. As such, most small bowel carcinomas are found at advanced stages and carry a poor prognosis. Oncologic surgical resection is the treatment of choice for patients with locoregional disease with little evidence available to guide adjuvant therapy. Patients with metastatic disease are treated with systemic chemotherapy, and surgery is reserved for palliation in this population. Prognosis is poor with few long-term survivors reported.

Adjuvant chemotherapy for resected duodenal adenocarcinoma: a case-matched analysis in nation wide cohort

BACKGROUND

Duodenal adenocarcinoma (DA) is a rare tumor for which survival data on adjuvant chemotherapy in patients after surgical treatment are unclear. This case-matched study in a nationwide cohort aims to investigate the benefit of adjuvant chemotherapy for patients with resectable DA on overall survival.

METHODS

All patients diagnosed with DA and intestinal type periampullary adenocarcinoma (PVA) in the Netherlands between 2000 and 2015 were included (n = 1316). Patients with disease stages II and III who underwent resection and adjuvant chemotherapy were matched (1:2), based on identified covariates associated with OS, with patients who underwent surgery alone. Overall survival was compared using Kaplan-Meier estimates.

RESULTS

The median OS was 49.9 months in patients who underwent curative resection (n = 649). Univariate and multivariate analysis showed a significant influence of age, lymph node involvement, and T- stage on survival. The group of patients receiving adjuvant treatment consisted of 43 patients and the non-adjuvant group of 83 case-matched patients. The median OS of the complete matched cohort (n = 126) was 26.9 months. No statistically significant survival benefit was found for the adjuvant group as compared to the group treated with surgery alone (median OS = 34.4 months and 23.0 months, p = 0.20).

CONCLUSION

This population-based, case-matched analysis demonstrates no statistically significant survival benefit for adjuvant chemotherapy after curative resection in stages II and III patients. Future studies with specified treatment regimens as well as thorough stratification for prognostic factors will be required in order to more definitively determine the role of adjuvant therapy.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of gastrointestinal cancer

Gastrointestinal (GI) cancers, including esophageal, gastroesophageal junction, gastric, duodenal and distal small bowel, biliary tract, pancreatic, colon, rectal, and anal cancer, comprise a heterogeneous group of malignancies that impose a significant global burden. Immunotherapy has transformed the treatment landscape for several GI cancers, offering some patients durable responses and prolonged survival. Specifically, immune checkpoint inhibitors (ICIs) directed against programmed cell death protein 1 (PD-1), either as monotherapies or in combination regimens, have gained tissue site-specific regulatory approvals for the treatment of metastatic disease and in the resectable setting. Indications for ICIs in GI cancer, however, have differing biomarker and histology requirements depending on the anatomic site of origin. Furthermore, ICIs are associated with unique toxicity profiles compared with other systemic treatments that have long been the mainstay for GI cancer, such as chemotherapy. With the goal of improving patient care by providing guidance to the oncology community, the Society for Immunotherapy of Cancer (SITC) convened a panel of experts to develop this clinical practice guideline on immunotherapy for the treatment of GI cancer. Drawing from published data and clinical experience, the expert panel developed evidence- and consensus-based recommendations for healthcare professionals using ICIs to treat GI cancers, with topics including biomarker testing, therapy selection, and patient education and quality of life considerations, among others.

Interventional gastroenterology in oncology

Cancer is one of the foremost health problems worldwide and is among the leading causes of death in the United States. Gastrointestinal tract cancers account for almost one third of the cancer-related mortality globally, making it one of the deadliest groups of cancers. Early diagnosis and prompt management are key to preventing cancer-related morbidity and mortality. With advancements in technology and endoscopic techniques, endoscopy has become the core in diagnosis and management of gastrointestinal tract cancers. In this extensive review, the authors discuss the role endoscopy plays in early detection, diagnosis, and management of esophageal, gastric, colorectal, pancreatic, ampullary, biliary tract, and small intestinal cancers.

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.

Impact of gastric and bowel surgery on gastrointestinal drug delivery

General surgical procedures on the gastrointestinal tract are commonly performed worldwide. Surgical resections of the stomach, small intestine, or large intestine can have a significant impact on the anatomy and physiological environment of the gastrointestinal tract. These physiological changes can affect the effectiveness of orally administered formulations and drug absorption and, therefore, should be considered in rational drug formulation design for specific pathological conditions that are commonly associated with surgical intervention. For optimal drug delivery, it is important to understand how different surgical procedures affect the short-term and long-term functionality of the gastrointestinal tract. The significance of the surgical intervention is dependent on factors such as the specific region of resection, the degree of the resection, the adaptive and absorptive capacity of the remaining tissue, and the nature of the underlying disease. This review will focus on the common pathological conditions affecting the gastric and bowel regions that may require surgical intervention and the physiological impact of the surgery on gastrointestinal drug delivery. The pharmaceutical considerations for conventional and novel oral drug delivery approaches that may be impacted by general surgical procedures of the gastrointestinal tract will also be addressed.

Clinical Outcome of Resected Non-Ampullary Duodenal Adenocarcinoma: A Single Center Experience

(1) Background: This study identified the clinical outcome and prognostic factors of resected non-ampullary duodenal adenocarcinoma (NADA) in a single tertiary cancer center. (2) Methods: The medical records of 109 patients with NADA who underwent curative surgery between 2000 and 2018 were reviewed retrospectively. (3) Results: The mean age was 62.4 years with a male predominance (70.6%). The majority of tumors were located at the 2nd portion (58.7%). Fifty-seven patients (52.3%) had symptoms at diagnosis. CA19-9 was elevated in 32 patients (29.4%). Of this cohort, most patients were diagnosed as stage III (64.2%). The median overall survival was 92.9 months, and the 1-, 3-, and 5-year survival rates were 84.4%, 71.6%, and 53.7%, respectively. In univariate and multivariate analysis, age, symptoms, CA19-9, and margin status were associated with overall survival and symptoms, CA19-9 and margin status were also associated with recurrence. When correlating symptoms with stages, patients with symptoms at diagnosis had more advanced stages (all p < 0.001). (4) Conclusion: Old age, elevated CA19-9, symptoms, and margin status were independent prognostic factors of NADA, and the patients with symptoms at diagnosis tend to have more advanced stages and a poor prognosis.

Case report: Neurofibromatosis type 1 gastrointestinal stromal tumor and small bowel adenocarcinoma with a novel germline NF1 frameshift mutation

A synchronous case of small bowel adenocarcinoma(SAB) is reported, accompanied with gastrointestinal stromal tumor(GIST),and gangliocytomain in an elderly woman with neurofibromatosis type 1 (NF-1). A 67-year-old female was hospitalized with the chief complaint of abdominal pain, the computed tomography scan indicated a large bowel mass. Multiple tumors were found in the small intestine, through which two larger tumors (7 cm and 1.5 cm) were resected. A novel germline NF1 mutation and a PMS2 mutation were identified after genetic testing, followed by the exploration of possible relationship between them in promoting tumorigenesis. Our results suggest multiple gastrointestinal tumors emerging in NF1 patients, and genetic testing can better guide postoperative treatment in a more efficient way.

Potential biomarkers and immune characteristics of small bowel adenocarcinoma

Small bowel adenocarcinoma (SBA) is a gastrointestinal malignancy with low incidence but poor prognosis, and its pathogenesis is still unclear. This study aimed to explore potential disease-causing biomarkers of SBA. The gene expression datasets of SBA and normal samples were downloaded from the Gene Expression Omnibus database. First, differential gene expression analysis and weighted gene coexpression network analysis (WGCNA) were performed. Common genes (CGs) were obtained by intersection of differentially expressed genes (DEGs) and optimal modal genes of WGCNA. Subsequently, a protein‒protein interaction network was established to screen hub genes, and target genes were obtained by Lasso regression analysis of hub genes. An SBA risk prediction model was established based on target genes. The prediction accuracy of the model was evaluated by the area under the receiver operating characteristic curve (AUC). The levels of immune cell infiltration and activation of immune pathways were compared between SBA and normal samples using the "ggpubr" and "reshape2" packages. A total of 1058 DEGs were identified. WGCNA showed that the signature gene in the brown module was significantly associated with SBA (p = 7E−17), and 469 CGs were obtained. Four target genes (APOA4, APOB, COL1A2, FN1) were identified and showed excellent prediction of SBA risk (AUC = 0.965). In addition, active dendritic cells and macrophages showed higher infiltration levels in SBA. Meanwhile, the APC_co_stimulation pathway and parainflammation pathway were strongly active in SBA. Four target genes (APOA4, APOB, COL1A2, FN1) may be involved in the pathogenesis of small bowel adenocarcinoma.

Suppressed Cellular Senescence Mediated by T-box3 in Aged Gastric Epithelial Cells may Contribute to Aging-related Carcinogenesis

Aging is a risk factor for cancers in various organs. Recent advances in the organoid culturing system have made it viable to investigate the influence of aging utilizing these mini organs. In this study, we aimed to examine the implications of aging for gastric carcinogenesis. Gastric organoids established from aged mice grew larger, proliferated vigorously, and survived longer than that from young mice. Because Wnt/β-catenin signaling was intensified in the aged organoids and because removal of Wnt-related factors diminished their proliferation, we investigated for Wnt target gene that contributed to enhanced proliferation and discovered that the aged organoids expressed the transcription factor T-box3 (Tbx3), which has been reported to suppress cellular senescence. Indeed, cellular senescence was suppressed in the aged organoids, and this resulted from enhanced G2-M transition. As for the mechanism involved in the intensified Wnt/β-catenin signaling, we identified that Dickkopf3 (Dkk3) expression was reduced in the aged organoids due to methylation of the Dkk3 gene. Finally, the expression of TBX3 was enhanced in human atrophic gastritis and even more enhanced in human gastric cancers. In addition, its expression correlated positively with patients' age. These results indicated that the emergence of antisenescent property in aged gastric organoids due to enhanced Tbx3 expression led to accelerated cellular proliferation and organoid formation. Because the enhanced Tbx3 expression seen in aged gastric organoids was also observed in human gastric cancer tissues, this Dkk3-Wnt-Tbx3 pathway may be involved in aging-related gastric carcinogenesis.

SIGNIFICANCE

This work provides an insight into the mechanism involved in aging-related gastric carcinogenesis through studies utilizing organoids established from young and aged murine stomachs.

First case report of neoadjuvant gemcitabine and S-1 for locally advanced unresectable duodenal adenocarcinoma

Background

The usefulness of neoadjuvant chemotherapy for patients with duodenal adenocarcinoma remains unclear. We report the case of a successfully resected duodenal adenocarcinoma managed by neoadjuvant chemotherapy using gemcitabine and S-1.

Case presentation

A 72-year-old female presented with a one-week history of abdominal bloating and vomiting after meals. Esophagogastroduodenoscopy revealed a circumferential epithelial lesion in the second portion of the duodenum. Abdominal computed tomography scan revealed thickened walls and narrowing of the duodenum. Further, an adenocarcinoma was noted on biopsy. Though she was diagnosed with duodenal adenocarcinoma, pancreatic cancer could not be completely ruled out. Therefore, she underwent neoadjuvant chemotherapy using gemcitabine and S-1 after bypass surgery. After six chemotherapy cycles, the tumor significantly reduced in size. Further, lymph nodes and distant metastases were not noted on abdominal computed tomography. The patient underwent pancreaticoduodenectomy. Pathological examination revealed a 0.5-mm lesion and surrounding fibrosis at the duodenum, distal from the ampulla of Vater and the pancreas. Her postoperative course was almost uneventful, and she was discharged on the 31st postoperative day. The patient was followed up and had no tumor recurrence at 24 months after surgery.

Conclusion

Neoadjuvant chemotherapy with gemcitabine and S-1 was useful in reducing the size of a duodenal adenocarcinoma. This finding would aid physicians in managing patients that present with a similar presentation.

Fluctuating methylation clocks for cell lineage tracing at high temporal resolution in human tissues

Molecular clocks that record cell ancestry mutate too slowly to measure the short-timescale dynamics of cell renewal in adult tissues. Here, we show that fluctuating DNA methylation marks can be used as clocks in cells where ongoing methylation and demethylation cause repeated 'flip-flops' between methylated and unmethylated states. We identify endogenous fluctuating CpG (fCpG) sites using standard methylation arrays and develop a mathematical model to quantitatively measure human adult stem cell dynamics from these data. Small intestinal crypts were inferred to contain slightly more stem cells than the colon, with slower stem cell replacement in the small intestine. Germline APC mutation increased the number of replacements per crypt. In blood, we measured rapid expansion of acute leukemia and slower growth of chronic disease. Thus, the patterns of human somatic cell birth and death are measurable with fluctuating methylation clocks (FMCs).

Development and validation of prognostic nomograms for patients with metastatic small bowel adenocarcinoma: a retrospective cohort study

We aimed to explore factors associated with prognosis in patients with metastatic small bowel adenocarcinoma (SBA) as well as to develop and validate nomograms to predict overall survival (OS) and cancer-specific survival (CSS). Relevant information of patients diagnosed between 2004 and 2016 was extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Nomograms for predicting 1- and 3-year OS and CSS were established with potential risk factors screened from multivariate cox regression analysis. The discrimination and accuracy of the nomograms were assessed by concordance index (C-index), calibration plots, and the area under receiver operating characteristic curve (AUC). In total, 373 SBA patients with M1 category were enrolled. Multivariate analysis revealed that age, size and grade of primary tumor, primary tumor surgery, and chemotherapy were significant variables associated with OS and CSS. The C-index values of the nomogram for OS were 0.715 and 0.687 in the training and validation cohorts, respectively. For CSS, it was 0.711 and 0.690, respectively. Through AUC, decision curve analysis (DCA) and calibration plots, the nomograms displayed satisfactory prognostic predicted ability and clinical application both in the OS and CSS. Our models could be served as a reliable tool for prognostic evaluation of patients with metastatic SBA, which are favorable in facilitating individualized survival predictions and clinical decision-making.

Microsatellite Instability Analysis and Its Prognostic Value in Invasive Nonampullary Duodenal Adenocarcinoma

PURPOSE

Nonampullary duodenal adenocarcinoma (NADA) is a rare disease. Although several prognostic factors have been reported for this disease, they remain controversial due to their rarity. In this study, we retrospectively analyzed 54 cases of invasive NADA, focusing on the microsatellite instability (MSI) phenotype, programmed cell death-ligand 1 (PD-L1) expression, and prognostic factors.

METHODS

Expression of the PD-L1 protein and cell differentiation markers in tumors was detected by immunohistochemistry. Microsatellite markers (NR-21, NR-22, NR-24, BAT-25, and BAT-26) were amplified for MSI assessment by PCR.

RESULTS

The incidence of MSI in invasive NADA was 35.2%. No significant correlation between the MSI phenotype and clinicopathological factors was observed. Positive expression of PD-L1 by immune cells was common in advanced-stage disease (p = 0.054), and positive expression of PD-L1 in cancer cells correlated significantly with the histologically undifferentiated type (p = 0.016). Kaplan-Meier survival analysis demonstrated a significantly better overall survival (OS) in patients with MSI (p = 0.013) and at early-stage disease (p = 0.000) than in those with microsatellite-stable or at late tumor stages. Univariate and multivariate analyses showed that MSI (hazard ratio [HR]: 0.282, 95% confidence interval [CI]: 0.106-0.751, p = 0.011) and early tumor stage (stage I-II) (HR: 8.81, 95% CI: 2.545-30.500, p = 0.001) were independent better prognostic factors of OS.

CONCLUSIONS

MSI and early tumor stage (stage I-II) were independent better prognostic factors of OS. A high proportion of MSI phenotypes and positive PD-L1 expression may be helpful for identifying immune checkpoint inhibitors as a novel therapeutic strategy.

Molecular Landscape of Small Bowel Adenocarcinoma

Small bowel adenocarcinoma (SBA) is a rare malignancy, with lower incidence, later stage at diagnosis, and poor overall prognosis compared to other cancers of the gastrointestinal tract. Owing to the rarity of the disease along with the paucity of high-quality tissue samples and preclinical models, little is known about the molecular alterations characteristic of SBA. This is reflected by the fact that the clinical management of SBA is primarily extrapolated from colorectal cancer (CRC). Recent advances in genomic profiling have highlighted key differences between these tumors, establishing SBA as a molecularly unique intestinal cancer. Moreover, comprehensive molecular analysis has identified a relatively high incidence of potentially targetable genomic alterations in SBA, predictive of response to targeted and immunotherapies. Further advances in our knowledge of the mutational and transcriptomic landscape of SBA, guided by an increased understanding of the molecular drivers of SBA, will provide opportunities to develop novel diagnostic tools and personalized therapeutic strategies.

Therapeutic Strategies for Patients with Advanced Small Bowel Adenocarcinoma: Current Knowledge and Perspectives

Small bowel adenocarcinoma (SBA) is diagnosed at an advanced (unresectable or metastatic) tumor stage in approximately one-third of cases. This is partly due to the non-specific symptomatology and limitations in endoscopic and radiologic detection methods. In this context, the prognosis remains poor and systemic chemotherapy appears to benefit patients when compared to best supportive care alone, despite the absence of randomized controlled trials. The results of a recent large prospective cohort (ARCAD-NADEGE) reported that the absence of chemotherapy was a predictive factor for a lower overall survival (OS) even though poor differentiation and SBA associated with Crohn's disease correlate with poor prognosis. In retrospective series, the median OS ranges from approximately 9 to 18 months with current treatment approaches. A combination of a fluoropyrimidine and oxaliplatin (FOLFOX or CAPOX) appears to be the most utilized and effective first-line chemotherapy regimen. Other front-line alternatives are the combination of 5-FU and cisplatin or fluoropyrimidine and irinotecan (FOLFIRI). In second-line, FOLFIRI is an effective option after progression on platinum-based therapy. Taxane-based therapy appears to be an alternative option, but further evaluation in larger series is needed. To a limited extent, the role of surgical resection for metastatic disease appears to be a valid option, though this approach has not been evaluated in prospective clinical studies. Due to the rareness of the disease, inclusion in clinical trials should be prioritized, and there is hope that targeted therapies and immunotherapy may enter the therapeutic arsenal for these patients.

Gall Bladder Disease and the Risk of Small Bowel Cancer-Results from a Nationwide Swedish Cohort Study

BACKGROUND AND AIMS

Small bowel cancer is a rare but rising malignancy. The etiology is poorly understood and there is a need for large-scale studies. Gallbladder disease (GBD), inducing localized inflammation, has been suggested to increase small bowel cancer risk.

METHODS

We retrieved nationwide data from Sweden's 28 pathology departments on all adults (age 20-79) with pathology-confirmed GBD diagnosed in 1965-2017. In total 156,390 GBD patients were matched with up to 5 matched comparators from the general population and follow-up started one year after GBD diagnosis. We used stratified Cox regression to calculate hazard ratios (HRs) for small bowel adenocarcinoma, adenomas, and carcinoids.

RESULTS

During a median follow-up of 12 years, we identified 92 small bowel adenocarcinomas, 132 adenomas, and 81 carcinoid tumors in the GBD cohort. Corresponding incidence rates were 4.8, 6.9, and 4.2 per 100,000 person-years (PY), compared to 3.2, 3.2, and 1.8 in matched comparators. The adjusted HR was 1.42 (95% CI = 1.08-1.87) for small bowel adenocarcinoma, 1.79 (95% CI = 1.41-2.27) for adenoma, and 2.07 (95% CI = 1.52-2.81) for carcinoid. The excess cancer risk was most pronounced during the first year of follow-up for adenocarcinomas and during the first six years for adenomas while for carcinoids the HR peaked 10-15 years after start of follow-up.

CONCLUSIONS

In this nationwide cohort study, GBD was associated with an increased risk of small bowel cancer. The excess risk of small bowel adenocarcinoma was mainly seen during the first years of follow-up while small bowel carcinoid risk peaked 11-16 years after GBD diagnosis.

Prognostic Factors and Clinical Characteristics of Duodenal Adenocarcinoma With Survival: A Retrospective Study

Background

To evaluate the clinical risk factors that influence the overall survival in patients with duodenal adenocarcinoma (DA) after tumor resection.

Methods

This study retrospectively analyzed 188 patients who underwent tumor resection for DA between January 2005 and June 2020 at Xiangyang Central Hospital.

Results

The median survival of the patients who underwent resectional operation was 54 months, longer than of those who underwent palliative surgery (20.8 months) (2,916.17; 95% CI, 916.3−9,280.5; p < 0.001). Survival of non-ampullary duodenal carcinoma patients (50.3 months; 95% CI, 39.7−61.8) was similar to that of ampullary duodenal carcinoma patients (59.3 months; 95% CI, 38.6−66.7) but was significantly better than that of papillary adenocarcinoma patients (38.9 months; 95% CI, 29.8−54.8; p = 0.386). Those with intestinal-type ductal adenocarcinomas had a longer median overall survival than those with the gastric type (61.8 vs. 46.7 months; p < 0.01) or pancreatic type (32.2 months; p < 0.001). Clinical DA samples had significantly diverse expressions of ATG12, IRS2, and IGF2. Higher expressions of the ATG12 and IRS2 proteins were significantly correlated with worse survival. Multivariate Cox regression analysis revealed that lymph node metastasis (hazard ratio (HR), 6.44; 95% CI, 3.68−11.27; p < 0.0001), margin status (HR, 4.94; 95% CI, 2.85−8.54; p < 0.0001), and high expression of ATG12 (HR, 1.89; 95% CI, 1.17−3.06; p = 0.0099) were independent prognostic factors negatively associated with survival in patients undergoing curative resection. There was no survival difference between the groups with ampullary, non-ampullary, and papillary adenocarcinomas treated with adjuvant chemotherapy (p = 0.973).

Conclusion

Gastric/pancreatic type, high expression of ATG12, lymph node metastases, and margin status were negative prognosticators of survival in patients with DAs than in those with tumor anatomical location. Curative resection is the best treatment option for appropriate patients.

OLFM4-RET fusion is an oncogenic driver in small intestine adenocarcinoma

Small intestine adenocarcinoma is a rare intestinal malignancy with distinct clinical, pathological, and molecular characteristics. Recently, a fusion of the intestinal stem-cell marker olfactomedin 4 (OLFM4) and the proto-oncogene RET has been identified in a small intestine adenocarcinoma patient. Here we investigated the biological effects of OLFM4-RET fusion and whether it can initiate tumorigenesis in small intestine. OLFM4 expression was found to be frequently lost or reduced in human small intestine adenocarcinoma, and its downregulation correlated with high tumor grade and advanced tumor stage. Expression of OLFM4-RET fusion-induced cellular transformation in HEK293 cells and blocked RET-induced inhibition of colony growth in HuTu 80 small intestine adenocarcinoma cells. Further, expression of OLFM4-RET activated the RAS-RAF-MAPK and STAT3 cell signaling pathways in both HEK293 cells and HuTu 80 cells. OLFM4-RET expression in HEK293 cells upregulated multiple families of genes related to carcinogenesis, cancer progression, and metastasis. Targeted expression of OLFM4-RET in the small intestine led to the development of hyperplasia, adenoma, or adenocarcinoma in transgenic mice. Our study suggests that OLFM4-RET is an oncogenic driver of small intestine tumorigenesis. Therefore, the small intestine adenocarcinoma patients with OLFM4-RET fusion may benefit from treatment with RET kinase inhibitor.

Histopathologic discrepancies between endoscopic forceps biopsy and endoscopic resection specimens in nonampullary duodenal epithelial tumors

For patients with nonampullary duodenal epithelial tumors (NADETs), endoscopic forceps biopsy results that reflect the final histopathologic results of the entire lesion are indispensable for accurate diagnosis and appropriate treatment modality selection. This study aimed to investigate the histopathologic discrepancies between endoscopic forceps biopsy and endoscopic resection specimens in NADETs and to elucidate the factors contributing to such discrepancies.This retrospective observational study included 105 patients (105 lesions) who underwent endoscopic resection for NADETs at the Pusan National University Hospital between May 2006 and October 2019. NADETs were classified as low-grade intraepithelial neoplasms (LGINs), high-grade intraepithelial neoplasms (HGINs), or adenocarcinomas. Following slide reviews, the histopathologic concordance between endoscopic forceps biopsy and endoscopic resection specimens was assessed for each case.The histopathologic discrepancy rate between endoscopic forceps biopsy and endoscopic resection specimens was 19.0% (20/105 lesions). Among the 20 diagnostically discordant lesions, up- and downgrade of the histopathologic diagnosis occurred in 17 and 3 lesions, respectively. The predominant discrepancies involved upgrades from LGIN to HGIN (n = 14) and upgrades from LGIN to adenocarcinomas (n = 2). The 3 downgraded cases included 2 from LGIN to inflammation and 1 from HGIN to LGIN. In the multivariate analyses, the old age (>67 years) was the only factor significantly associated with histopathologic upgrade (odds ratio 4.553, 95% confidence interval 1.291-15.939; P = .018).Considerable histopathologic discrepancies were observed between endoscopic forceps biopsy and endoscopic resection specimens in NADETs. Older age was significantly associated with these discrepancies.

Impact of Tumor Location on Patient Outcomes in Small Bowel Cancers

BACKGROUND

Small bowel cancers are rare gastrointestinal malignancies and tumor location impact on outcomes is unclear.

MATERIAL AND METHODS

A retrospective review was performed on stage I to IV small bowel cancer cases from 2000 to 2017 in British Columbia, Canada. Baseline patient characteristics, disease-free survival (DFS) and overall survival (OS) were evaluated by tumor location and systemic therapy use patterns were summarized.

RESULTS

Of 340 patients included, primary tumor distribution was: duodenum (51.2%), ileum (19.1%), jejunum (18.5%), and unspecified (11.2%). Median DFS for stage I to III disease was 37.7, 49.1, and 26.7 months for duodenal, jejunal, and ileal tumors (P = .018). Median OS was 9.6, 35.2, and 20.1 months for duodenal, jejunal, and ileal tumors (P < .0001). Compared to duodenal primaries, both jejunal and ileal tumors were associated with significantly improved OS (HR 0.43, P < .001 for jejunal; HR 0.71, P = .035 for ileal). Adjuvant therapy was given to 21.6% of stage II and 50.6% of stage III cancers. Among patients with metastatic disease, median OS was 4.2, 11.4, and 6.9 months for duodenal, jejunal, and ileal tumors (P = .0019). Jejunal tumors had the best prognosis (HR 0.48, P = .001 vs. duodenum).

CONCLUSION

Survival differences exist when small bowel cancers were assessed by tumor location, and jejunal tumors portended better prognosis overall.

Lower Extremity Varicose Veins: An Unusual Presentation of Small Bowel Leiomyosarcoma

Leiomyosarcomas (LMSs) are extremely rare and comprise only 1.2% of small bowel malignancies. Advancements in immunohistochemical techniques have allowed for the differentiation between LMSs and gastrointestinal stromal tumors. LMSs remain difficult to detect via endoscopy and require a more intricate diagnostic approach. The staging and sizing of these tumors are important prognostic indicators. We report a case of a 67-year-old male who presented with bulging lower extremity veins, abdominal bloating, and weight loss. A CT of the abdomen and pelvis revealed a pelvic mass arising from the small bowel and a metastatic hepatic lesion, which was found to be compressing the inferior vena cava. A biopsy of the hepatic lesion confirmed the diagnosis of metastatic LMS.

The Risk of Malignancies in Celiac Disease-A Literature Review

Celiac disease (CeD) is an immune-mediated enteropathy precipitated by ingestion of gluten in genetically predisposed individuals. Considering that CeD affects approximately 1% of the Western population, it may be considered a global health problem. In the large majority of cases, CeD has a benign course, characterized by the complete resolution of symptoms and a normal life expectancy after the beginning of a gluten-free-diet (GFD); however, an increased risk of developing malignancies, such as lymphomas and small bowel carcinoma (SBC), has been reported. In particular, enteropathy-associated T-cell lymphoma (EATL), a peculiar type of T-cell lymphoma, is characteristically associated with CeD. Moreover, the possible association between CeD and several other malignancies has been also investigated in a considerable number of studies. In this paper, we aim to provide a comprehensive review of the current knowledge about the associations between CeD and cancer, focusing in particular on EATL and SBC, two rare but aggressive malignancies.

Medullary Carcinoma of the Gastrointestinal Tract: Report on Two Cases with Immunohistochemical and Molecular Features

Medullary carcinoma of the colon is a rare histological variant characterized by a poorly differentiated morphology, an aberrant immunophenotype, and microsatellite instability. Despite the lack of glandular differentiation, medullary carcinoma is reported to have a good prognosis. It is typically located in the right colon and frequently affects older women. Due to its clinical, histological, biological, and genetic peculiarity, medullary carcinoma requires an accurate diagnosis and the awareness of this diagnostic possibility. We describe the morphological, immunohistochemical, and molecular findings of two interesting cases, the first one in the right colon of a patient and the second one in the terminal ileum of a patient with Crohn's disease. Deeper knowledge of all the biological and clinical features will allow appropriate and specific treatment of this tumor in the future.

Small bowel adenocarcinoma: Case reports and review of the literature

Small bowel adenocarcinomas (SBAs) are rare tumors of the gastrointestinal tract. Patients often present with advanced disease due to nonspecific symptoms and delayed diagnoses. In combination with non-uniform treatment paradigms, patients who present with SBA often have poor prognoses. In this case series, we present four cases of SBA and review the most recent literature with regard to diagnosis and management. One patient presented with iron-deficient anemia (IDA), and three patients presented with clinical obstruction. The patient with IDA was subjected to protracted investigations, whereas the three patients with obstruction were diagnosed quickly after presentation. All four patients underwent surgical resection, and one patient was eligible for post-operative adjuvant chemotherapy. SBA should be highly suspected in patients who present with occult gastrointestinal bleeds, and appropriate investigations must be initiated. Following diagnosis, surgical resection is the mainstay of treatment for this disease. Our review supports the use of both neoadjuvant and adjuvant chemotherapy in localized disease.

Association between intestinal neoplasms and celiac disease: A review

Celiac disease (CD) is a chronic immune-mediated intestinal disease with genetic susceptibility. It is characterized by inflammatory damage to the small intestine after ingestion of cereals and products containing gluten protein. In recent years, the global prevalence rate of CD has been approximately 1%, and is gradually increasing. CD patients adhere to a gluten-free diet (GFD) throughout their entire life. However, it is difficult to adhere strictly to a GFD. Untreated CD may be accompanied by gastrointestinal symptoms, such as diarrhea, abdominal pain, and extraintestinal symptoms caused by secondary malnutrition. Many studies have suggested that CD is associated with intestinal tumors such as enteropathy-associated T-cell lymphoma (EATL), small bowel cancer (SBC), and colorectal cancer. In this study, we reviewed related studies published in the literature to provide a reference for the prevention and treatment of intestinal tumors in patients with CD. Compared with the general population, CD patients had a high total risk of SBC and EATL, but not colorectal cancer. The protective effect of GFD on CD-related malignancies is controversial. Further studies are needed to confirm whether GFD treatment can reduce the risk of intestinal neoplasms in CD.

Gastrointestinal cancer characteristics in Lebanon

BACKGROUND AND STUDY AIMS

Gastrointestinal (GI) cancer is one of the top five common cancers in Lebanon. To implement a strategy for screening and early diagnosis through the initiation of prevention programs, a detailed study of GI cancers in Lebanon was conducted by focusing on the frequency and characteristics of each type.

PATIENTS AND METHODS

This retrospective study was conducted in Lebanon between 2001 and 2015 and included patients diagnosed with different GI cancer types. Data were collected from the registry of the National Institute of Pathology (NIP). The frequency of each type was calculated according to sex, age at diagnosis, anatomic location, histological type, and stage.

RESULTS

The total number of patients diagnosed with GI cancers who had their histology done at the NIP between 2001 and 2015 was 5239. The sex (male/female) ratio was 1.016, with a mean age of 62.2 years. Colorectal cancer ranked first among GI cancers, with more than half of the cases (53.4%). More than 70% of the cases were located on the left side, followed by gastric (15.5%) and pancreatic (12.7%) cancers. Regarding gastric cancer, cardia became the dominant location. A shift from squamous cell carcinoma to adenocarcinoma in esophageal cancer was found during this period. Also, most GI cancers in Lebanon were diagnosed in the late stages.

CONCLUSION

This study is the first to evaluate GI cancers in Lebanon, which will help in screening strategies and burden studies.

Molecular profiling and identification of prognostic factors in Chinese patients with small bowel adenocarcinoma

Small bowel adenocarcinoma (SBA) is a rare malignancy with a poor prognosis and limited treatment options. Despite prior studies, molecular characterization of this disease is not well defined, and little is known regarding Chinese SBA patients. In this study, we conducted multigene next-generation sequencing and 16S ribosomal RNA gene sequencing on samples from 76 Chinese patients with surgically resected primary SBA. Compared with colorectal cancer and Western SBA cohorts, a distinctive genomic profile was revealed in Chinese SBA cohorts. According to the levels of clinical actionability to targetable alterations stratified by OncoKB system, 75% of patients harbored targetable alterations, of which ERBB2, BRCA1/2, and C-KIT mutations were the most common targets of highest-level actionable alterations. In DNA mismatch repair-proficient (pMMR) patients, significant associations between high tumor mutational burden and specific genetic alterations were identified. Moreover, KRAS mutations/TP53 wild-type/nondisruptive mutations (KRAS^mut /TP53^wt/non-dis ) were independently associated with an inferior recurrence-free survival (hazard ratio [HR] = 4.21, 95% confidence interval [CI] = 1.94-9.14, P < .001). The bacterial profile revealed Proteobacteia, Actinobacteria, Firmicutes, Bacteroidetes, Fusobacteria, and Cyanobacteria were the most common phyla in SBA. Furthermore, patients were clustered into three subgroups based on the relative abundance of bacterial phyla, and the distributions of the subgroups were significantly associated with the risk of recurrence stratified by TP53 and KRAS mutations. In conclusion, these findings provided a comprehensive molecular basis for understanding SBA, which will be of great significance in improving the treatment strategies and clinical management of this population.

Early detection of duodenal cancer by upper gastrointestinal-endoscopy in Lynch syndrome

Small bowel cancer (SBC) is the malignancy with the highest standardized incidence ratio in Lynch syndrome (LS) patients. Of all SBCs, about 50% are duodenal cancers (DCs), therefore being accessible by esophago-gastro-duodenoscopy (EGD) for surveillance. We asked whether early detection of DC is possible for LS patients undergoing surveillance by EGD and if surveillance should be limited to specific subgroups. Data for LS patients with DC were retrieved from the registry of the German Consortium for Familial Intestinal Cancer. Patients undergoing active surveillance by EGDs (surveillance group) were compared to those who did not (nonsurveillance group) regarding tumor stage at diagnosis. Union for International Cancer Control stages I-IIA were defined as early stage disease and IIB-IV as advanced stage disease. Statistical analysis was performed using Fisher's exact test. Among 2015 patients with pathogenic variants in any mismatch-repair-gene, 47 patients with 49 DCs were identified. In 10% of cases, patients were under 35 years at diagnosis; family and personal tumor history did not correlate with DC diagnosis. Pathogenic germline variants in MSH6, PMS2 or EPCAM were present in 10% of patients. Statistical analysis could be performed on 13 DC patients in the surveillance group and 14 in the nonsurveillance group. Early detection was possible for 71% of patients in the surveillance group and 29% of patients in the nonsurveillance group (P = .021). Early detection of DC by EGD in LS patients is feasible regardless of family history, mutational status and should start no later than 25 years of age.

Adenocarcinoma of the Jejunum: A Case Report and Literature Review

Small intestine cancers account for 1-3% of all gastrointestinal tumors, with only 11-25% of these tumors located in the jejunum. We report the case of a woman who has been experiencing abdominal pain for the last six months, accompanied by nausea, vomiting and appearance of dark-colored stools, who has lost 20 kg in weight during the last few months. Laboratory findings indicated anemia and no significant changes were identified in the abdominal ultrasound. By endoscopic examination of the stomach and duodenum and by colonoscopy, no infiltrations were found. Serum markers were elevated and CT scan of the abdomen showed thickening of a part of the jejunum wall with swollen lymph nodes in the mesentery, along the inferior vena cava and abdominal aorta, in the retroperitoneal space. By opening the abdominal cavity, we observed an infiltration in the initial part of the jejunum with an infiltration of the entire wall. Resection of the jejunum with related mesenthery, vessels and lymph nodes therein was performed. Histopathology revealed an invasive adenocarcinoma of the small intestine, with an invasion of all layers of the wall and mesentery. Adjuvant FOLFOX chemotherapy was introduced, 6 cycles in total, and following each cycle, tumor markers have been constantly decreasing. No relapse has been identified after nine months. Due to often deep position in the small intestine, atypical symptomatology and lack of screening, an early diagnosis is difficult. Surgical resection of the affected small intestine followed by an additional chemotherapy is the optimal treatment strategy.

Prognostic implication of SOX2 expression in small intestinal adenocarcinoma

The presence of KRAS mutation enhances the stem cell features of colorectal carcinoma cells containing mutant adenomatous polyposis coli (APC). However, their potential role in small intestinal adenocarcinoma remains elusive. Here, we aimed to investigate the clinical significance of cancer stem cell markers expression in the context of small intestinal adenocarcinoma with the KRAS genotype. SOX2, NANOG, and OCT4 expression were assessed by immunohistochemistry and digital image analysis, and their potential association with KRAS was further examined in 185 Korean patients with small intestinal adenocarcinomas, which were collected from 22 institutions in South Korea. Positive expression of SOX2, NANOG, and OCT4 was detected in 65 (35.1%), 94 (50.8%), and 82 (44.3%) of patients, respectively. Patients with high SOX2 (SOX2+) expression displayed worse overall survival compared to those with low SOX2 (SOX2-) expression (P < 0.001). Patients with SOX2+/mutant KRAS (KRAS^MT) (11.1 months) had significantly shorter overall survival than those with SOX2-/KRAS^WT (53.6 months) (P < 0.001). In multivariate analysis, SOX2+, distal location, high pT and pN categories, microsatellite stable, and absence of predisposing diseases were independent prognostic factors for worse overall survival. These results suggest that SOX2 expression has the potential to predict clinical outcomes in patients with small intestinal adenocarcinomas.