Immunophenotype and molecular characterisation of adenocarcinoma of the small intestine. Br J Cancer. 2010;102:144-150. [PMID: 19935793 PMCID: PMC2813754 DOI: 10.1038/sj.bjc.6605449]

Phase II Study of Panitumumab in RAS Wild-Type Metastatic Adenocarcinoma of Small Bowel or Ampulla of Vater

Lessons Learned.

Panitumumab has no clinical activity in metastatic RAS wild‐type small bowel adenocarcinoma (SBA) and ampullary adenocarcinoma (AAC), possibly due to the foregut and midgut derivation of small bowel and ampulla.

These results, along with findings from genomic characterization of SBA, suggest that SBA represents a unique intestinal malignancy and treatments should not be habitually extrapolated from colorectal cancer.

Further studies evaluating the benefit of targeted therapies exclusively in SBA and AAC are warranted.

Background.

Given the benefit of epidermal growth factor receptor (EGFR) monoclonal antibodies in colorectal cancer (CRC), we sought to evaluate the efficacy of panitumumab in metastatic RAS wild‐type small bowel adenocarcinoma (SBA) and ampullary adenocarcinoma (AAC).

Methods.

We conducted a single‐center, open‐label, single‐arm, Bayesian phase II trial. The primary objective was response rate (RR). Panitumumab was administered at a dose of 6 mg/kg intravenously (IV) every 14 days.

Results.

Nine patients (male/female 7:2, median age: 61 years [range: 40–74], Eastern Cooperative Oncology Group [ECOG] performance status 0/1: 2/7) were enrolled from September 2013 to October 2015. One patient had AAC (pancreaticobiliary subtype) and eight patients had SBA (three duodenal, five jejunal/ileal). Acneiform rash was the most common toxicity. The study was stopped early due to futility with no responses, stable disease (SD) in two patients, and progression of disease (PD) in seven patients. Median progression‐free survival (PFS) and overall survival (OS) were 2.4 and 5.7 months, respectively. No patients had extended RAS mutations (exons 2/3/4), but two patients had BRAF G469A and one patient had PIK3CA H1074R mutations.

Conclusion.

Panitumumab had no clinically meaningful activity in patients with metastatic RAS wild‐type SBA and AAC. Our findings may relate to the primarily midgut and foregut derivation of the small bowel and ampulla.

Practical Immunohistochemistry in Neoplastic Pathology of the Gastrointestinal Tract, Liver, Biliary Tract, and Pancreas

CONTEXT

- Immunomarkers with diagnostic, therapeutic, or prognostic values have been increasingly used to maximize the benefits of clinical management of patients with neoplastic diseases of the gastrointestinal tract, liver, biliary tract, and pancreas.

OBJECTIVES

- To review the characteristics of immunomarkers that are commonly used in surgical pathology practice for neoplasms of the gastrointestinal tract, liver, biliary tract, and pancreas, and to summarize the clinical usefulness of immunomarkers that have been discovered in recent years in these fields.

DATA SOURCES

- Data sources include literature review, authors' research data, and personal practice experience.

CONCLUSIONS

- Immunohistochemistry is an indispensable tool for the accurate diagnosis of neoplastic diseases of the gastrointestinal tract, liver, biliary tract, and pancreas. Useful immunomarkers are available to help distinguish malignant neoplasms from benign conditions, determine organ origins, and subclassify neoplasms that are morphologically and biologically heterogeneous. Specific immunomarkers are also available to help guide patient treatment and assess disease aggressiveness, which are keys to the success of personalized medicine. Pathologists will continue to play a critical role in the discovery, validation, and application of new biomarkers, which will ultimately improve patient care.

Lynch syndrome-related small intestinal adenocarcinomas

Lynch syndrome is an autosomal-dominant disorder caused by defective DNA mismatch repair (MMR) genes and is associated with increased risk of malignancies in multiple organs. Small-intestinal adenocarcinomas are common initial manifestations of Lynch syndrome. To define the incidence and characteristics of Lynch syndrome-related small-intestinal adenocarcinomas, meticulous familial and clinical histories were obtained from 195 patients with small-intestinal adenocarcinoma, and MMR protein immunohistochemistry, microsatellite instability, MLH1 methylation, and germline mutational analyses were performed. Lynch syndrome was confirmed in eight patients (4%), all of whom had synchronous/metachronous malignancies without noticeable familial histories. Small-intestinal adenocarcinomas were the first clinical manifestation in 37% (3/8) of Lynch syndrome patients, and second malignancies developed within 5 years in 63% (5/8). The patients with accompanying Lynch syndrome were younger (≤50 years; P=0.04) and more likely to have mucinous adenocarcinomas (P=0.003), and tended to survive longer (P=0.11) than those with sporadic cases. A meticulous patient history taking, MMR protein immunolabeling, and germline MMR gene mutational analysis are important for the diagnosis of Lynch syndrome-related small-intestinal adenocarcinomas. Identifying Lynch syndrome in patients with small-intestinal adenocarcinoma can be beneficial for the early detection and treatment of additional Lynch syndrome-related cancers, especially in patients who are young or have mucinous adenocarcinomas.

Clinical use of molecular targeted agents for primary small bowel adenocarcinoma: A multicenter retrospective cohort study by the Osaka Gut Forum

Primary small bowel adenocarcinoma (SBA) is a rare cancer for which effective treatment strategies have not yet been established. The results of previous retrospective studies suggest that chemotherapy contributes to a longer survival time in patients with SBA. However, there are few case reports about the efficacy of molecular targeted agent-containing chemotherapy for SBA. In the present study, the treatment and follow-up data of patients with SBA who received chemotherapy with or without molecular targeted agents were retrospectively analyzed. Each patient was treated in one of ten hospitals participating in the Osaka Gut Forum between April 2006 and March 2014. The following factors were evaluated: Age, sex, Eastern Cooperative Oncology Group performance status (PS), tumor location, tumor differentiation, chemotherapy regimen, resection of primary tumor, tumor biomarker expression, distant metastasis, best response under chemotherapy, time to disease progression, subsequent treatments, survival status and treatment toxicity. A total of 27 patients (17 males and 10 females; mean age, 63.4 years old; range, 36-83 years old) received chemotherapy due to non-curative tumor resection, unresectable tumor or post-operative recurrence. The median overall survival time was 14.8 months (range, 2-58 months). A univariate analysis revealed a PS of 0 (P=0.0228) and treatment with platinum-based chemotherapy (P=0.0048) were significant factors for an improved prognosis. An age-adjusted multivariate analysis also revealed that a platinum-based regimen was a significant positive prognostic factor (P=0.0373). Molecular targeted agents were administered to 8 patients, for whom it was their first- or second-line therapy. Among the 17 patients who received oxaliplatin-based chemotherapy as a first-line chemotherapy, a PS of 0 (P=0.0255) and treatment with bevacizumab (P=0.0121) were significant positive prognostic factors. Toxicities higher than Grade 3 occurred in 8/27 patients with SBA; however, serious side effects due to the molecular targeted agents were not experienced. The results of the present study indicate that chemotherapy containing molecular targeted agents is a well-tolerated and effective treatment option for SBA.

Suggestion of added value by bevacizumab to chemotherapy in patients with unresectable or recurrent small bowel cancer

PURPOSE

Standard therapy for advanced small bowel adenocarcinoma (SBA) has not yet been established. The present study assessed the efficacy and safety of chemotherapy (CT) in association with molecular targeting approaches for SBA.

METHODS

The histories of 33 advanced SBA patients from six different institutions in Japan, who received CT from 2008 to 2016, were retrospectively examined for background, clinical course and outcome.

RESULTS

Median patient age was 65 years (range 39-83). Primary tumor was located in the duodenum in 21 patients (67%), the ampulla of Vater in three patients (9%), the jejunum in seven patients (21%) and the ileum in one patient (3%). Histologically, well-to-moderately and poorly differentiated adenocarcinoma were identified in 20 (61%) and nine (27%) patients, respectively. Thirteen patients received a single CT regimen, seven patients received two types of CT regimen, and 13 patients received three or more CT regimens. As first-line CT, modified FOLFOX6, capecitabine plus oxaliplatin, and S-1 plus cisplatin were employed in 13, 1, and 4 patients, respectively. The response rate (RR) and median progression-free survival (PFS) were 25% and 6.0 months, respectively. Median overall survival (OS) was 13.0 months. Nine out of the 33 patients received bevacizumab-containing CT and three received cetuximab-containing CT. Median OS of bevacizumab-containing CT patients was 21.9 months. No unexpected serious adverse events were observed.

CONCLUSIONS

The analysis indicates that combination CT for advanced SBA is associated with modest efficacy and safety, and bevacizumab-containing CT may contribute to favorable outcome in these patients.

A phase II study of 5-fluorouracil/L-leucovorin/oxaliplatin (mFOLFOX6) in Japanese patients with metastatic or unresectable small bowel adenocarcinoma

BACKGROUND

Several studies have suggested that chemotherapy prolonged survival in patients with metastatic or recurrent small bowel adenocarcinoma (SBA); however, there is still no standard chemotherapy regimen. Here, we evaluated the efficacy and safety of a 5-fluorouracil (5-FU)/L-leucovorin (l-LV)/oxaliplatin (mFOLFOX6) protocol as a first-line therapy for patients with SBA.

PATIENTS AND METHODS

This was a multicenter, single-arm, open-label phase II study. Eligibility criteria included histologically confirmed adenocarcinoma, age 20-80 years, and an Eastern Cooperative Oncology Group performance status (PS) of 0-2. The primary endpoint was 1-year progression-free survival (PFS). The secondary endpoints included overall response rate (ORR), overall survival (OS), overall PFS, and safety.

RESULTS

Between April 2010 and November 2012, 24 patients were enrolled from 12 institutions. The median age of the patients was 63 years (range 31-79) and there was a male/female ratio of 18/6. The number of PS 0/1 patients was 17/7 and locally advanced/metastatic disease was seen in 2/22 patients, respectively. The primary tumor site was the duodenum in 14 patients (58%) and jejunum in 10 patients (42%). The median follow-up time was 14.7 months (3.7-40.3). The 1-year PFS was 23.3%. The ORR was 9/20 (45%). The median PFS and OS times were 5.9 months (95% confidence interval [CI] 3.0-10.2) and 17.3 months (95% CI 11.7-19.0), respectively. Major grade 3/4 toxicities were neutropenia (38%), anemia/peripheral neuropathy (25%), and stenosis (17%). There were no treatment-related deaths.

CONCLUSIONS

Although the primary endpoint was not met, mFOLFOX6 showed effective and good tolerance as a first-line treatment for SBA.

Non-ampullary-duodenal carcinomas: clinicopathologic analysis of 47 cases and comparison with ampullary and pancreatic adenocarcinomas

Literature on non-ampullary-duodenal carcinomas is limited. We analyzed 47 resected non-ampullary-duodenal carcinomas. Histologically, 78% were tubular-type adenocarcinomas mostly gastro-pancreatobiliary type and only 19% pure intestinal. Immunohistochemistry (n=38) revealed commonness of 'gastro-pancreatobiliary markers' (CK7 55, MUC1 50, MUC5AC 50, and MUC6 34%), whereas 'intestinal markers' were relatively less common (MUC2 36, CK20 42, and CDX2 44%). Squamous and mucinous differentiation were rare (in five each); previously, unrecognized adenocarcinoma patterns were noted (three microcystic/vacuolated, two cribriform, one of comedo-like, oncocytic papillary, and goblet-cell-carcinoid-like). An adenoma component common in ampullary-duodenal cancers was noted in only about a third. Most had plaque-like or ulcerating growth. Mismatch repair protein alterations were detected in 13% (all with plaque-like growth and pushing-border infiltration). When compared with ampullary (n=355) and pancreatic ductal (n=227) carcinomas, non-ampullary-duodenal carcinomas had intermediary pathologic features with mean invasive size of 2.9 cm (vs 1.9, and 3.3) and 59% nodal metastasis (vs 45, and 77%). Its survival (3-, 5-year rates of 57 and 57%) was similar to that of ampullary-duodenal carcinomas (59 and 52%; P=0.78), but was significantly better than the ampullary ductal (41 and 29%, P<0.001) and pancreatic (28 and 18%, P<0.001) carcinomas. In conclusion, non-ampullary-duodenal carcinomas are more histologically heterogeneous than previously appreciated. Their morphologic versatility (commonly showing gastro-pancreatobiliary lineage and hitherto unrecognized patterns), frequent plaque-like growth minus an adenoma component, and frequent expression of gastro-pancreatobiliary markers suggest that many non-ampullary-duodenal carcinomas may arise from Brunner glands or gastric metaplasia or heterotopic pancreatobiliary epithelium. The clinical behavior of non-ampullary-duodenal carcinoma is closer to that of ampullary-duodenal subset of ampullary carcinomas, but is significantly better than that of ampullary ductal and pancreatic cancers. The frequency of mismatch repair protein alterations suggest that routine testing should be considered, especially in the non-ampullary-duodenal carcinomas with plaque-like growth and pushing-border infiltration.

Bevacizumab combined with capecitabine and oxaliplatin in patients with advanced adenocarcinoma of the small bowel or ampulla of vater: A single-center, open-label, phase 2 study

BACKGROUND

Capecitabine with oxaliplatin (CAPOX) has previously demonstrated clinical activity in patients with small bowel adenocarcinoma (SBA) and ampullary adenocarcinoma (AAC). Herein, the authors conducted a phase 2 trial to evaluate the benefit of adding bevacizumab to CAPOX.

METHODS

In this phase 2, single-arm, single-center, open-label study, patients aged ≥18 years with untreated, advanced SBA or AAC were recruited. Patients received capecitabine at a dose of 750 mg/m² orally twice daily on days 1 to 14, oxaliplatin at a dose of 130 mg/m² intravenously on day 1, and bevacizumab at a dose of 7.5 mg/kg intravenously on day 1 of a 21-day cycle. The primary endpoint was progression-free survival (PFS) at 6 months. Secondary objectives included response rate, overall PFS, overall survival, and toxicity.

RESULTS

Between August 2011 and November 2014, a total of 30 patients were enrolled into the study (male/female ratio of 13/17; median age of 63 years [range, 33-78 years]; and 7 patients with an Eastern Cooperative Oncology Group performance status [ECOG PS] of 0, 20 patients with an ECOG PS of 1, and 3 patients with an ECOG PS of 2). Of the 30 patients, 23 (77%) had SBA (18 of duodenal origin and 5 of jejunal/ileal origin) and 7 patients (23%) had AAC (5 of pancreaticobiliary subtype, 1 of mixed subtype, and 1 of intestinal subtype). The most common grade 3 toxicities observed were fatigue and hypertension (7 patients each [23%]), neutropenia (6 patients [20%]), and diarrhea (3 patients [10%]) (toxicity was graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events [version 4.0]). The probability of PFS at 6 months was 68% (95% confidence interval [95% CI], 52% to 88%). The response rate was 48.3%, with 1 complete response and 13 partial responses; 10 patients achieved stable disease. At a median follow-up of 25.9 months, the median PFS was 8.7 months (95% CI, 4.9-10.5 months) and the median overall survival was 12.9 months (95% CI, 9.2-19.7 months).

CONCLUSIONS

The results of the current study indicate that CAPOX with bevacizumab is an active and well-tolerated regimen for patients with SBA and AAC. These findings support the need for further investigation into the clinical benefit of targeting angiogenesis in patients with SBA and AAC. Cancer 2017;123:1011-17. © 2016 American Cancer Society.

Methylation of MGMT Is Associated with Poor Prognosis in Patients with Stage III Duodenal Adenocarcinoma

BACKGROUND

O6-methylguanine-DNA methyltransferase (MGMT) methylation status has not been extensively investigated in duodenal adenocarcinoma (DA). The aim of this study was to evaluate the MGMT methylation status and examine its possible prognostic value in patients with stage III DA.

METHODS

Demographics, tumor characteristics and survival were available for 64 patients with stage III DA. MGMT methylation was detected by using MethyLight. A Cox proportional hazard model was built to predict survival, adjusted for clinicopathological characteristics and tumor molecular features, including the CpG island methylator phenotype (CIMP), microsatellite instability (MSI), and KRAS mutations.

RESULTS

MGMT methylation was detected in 17 of 64 (26.6%) patients, and was not correlated with sex, age, tumor differentiation, CIMP, MSI, or KRAS mutations. MGMT methylation was the only one factor associated with both overall survival (OS) and disease-free survival (DFS) on both univariate and multivariate analyses. In patients treated with surgery alone, MGMT-methylated group had worse OS and DFS when compared with MGMT-unmethylated group. However, in patients treated with chemotherapy/radiotherapy, outcomes became comparable between the two groups.

CONCLUSIONS

Our results demonstrate MGMT methylation is a reliable and independent prognostic factor in DAs. Methylation of MGMT is associated with poor prognosis in patients with stage III DAs.

Small Bowel Adenocarcinoma

Small bowel adenocarcinomas (SBAs) are rare tumors, but their incidence is increasing. The most common primary location is the duodenum. Even though SBAs are more often sporadic, some diseases are risk factors. Early diagnosis of small bowel adenocarcinoma remains difficult, despite significant radiologic and endoscopic progress. After R0 surgical resection, the main prognostic factor is lymph node invasion. An international randomized trial (BALLAD [Benefit of Adjuvant Chemotherapy For Small Bowel Adenocarcinoma] study) will evaluate the benefit of adjuvant chemotherapy. For metastatic disease, retrospectives studies suggest that platinum-based chemotherapy is the most effective treatment. Phase II studies are ongoing to evaluate targeted therapy in metastatic SBA.

Comprehensive molecular pathology analysis of small bowel adenocarcinoma reveals novel targets with potential for clinical utility

Small bowel accounts for only 0.5% of cancer cases in the US but incidence rates have been rising at 2.4% per year over the past decade. One-third of these are adenocarcinomas but little is known about their molecular pathology and no molecular markers are available for clinical use.

Using a retrospective 28 patient matched normal-tumor cohort, next-generation sequencing, gene expression arrays and CpG methylation arrays were used for molecular profiling.

Next-generation sequencing identified novel mutations in IDH1, CDH1, KIT, FGFR2, FLT3, NPM1, PTEN, MET, AKT1, RET, NOTCH1 and ERBB4. Array data revealed 17% of CpGs and 5% of RNA transcripts assayed to be differentially methylated and expressed respectively (p < 0.01). Merging gene expression and DNA methylation data revealed CHN2 as consistently hypermethylated and downregulated in this disease (Spearman −0.71, p < 0.001). Mutations in TP53 which were found in more than half of the cohort (15/28) and Kazald1 hypomethylation were both were indicative of poor survival (p = 0.03, HR = 3.2 and p = 0.01, HR = 4.9 respectively).

By integrating high-throughput mutational, gene expression and DNA methylation data, this study reveals for the first time the distinct molecular profile of small bowel adenocarcinoma and highlights potential clinically exploitable markers.

Clinicopathologic and prognostic associations of KRAS and BRAF mutations in small intestinal adenocarcinoma

Activating KRAS and/or BRAF mutations have been identified as predictors of resistance to anti-epidermal growth factor receptor (EGFR) chemotherapy in colorectal cancer. But the status of KRAS and BRAF mutations and their clinicopathologic and prognostic significance has not been extensively evaluated in small intestinal adenocarcinomas. In this work, the KRAS and BRAF genes in 190 surgically resected small intestinal adenocarcinoma cases were sequenced and their association with various clinicopathologic variables, including survival of the patients, was analyzed. KRAS or BRAF mutations were observed in 63 (33%) cases. Sixty-one cases had KRAS mutations and 2 had BRAF mutations and the two types of mutation were mutually exclusive. The majority of KRAS mutations were G>A transition (43/61 cases, 71%) or p.G12D (31/61 cases, 51%). The patients with mutant KRAS tended to have higher pT classifications (P=0.034) and more frequent pancreatic invasion (P=0.020) than those with wild-type KRAS. Multivariate logistic regression analysis showed that certain mutated KRAS subtypes (G>A transitions and G12D mutations) were significantly correlated with higher pT classification (P=0.015 and 0.004, respectively) than wild-type KRAS and other KRAS mutations. The patients with KRAS or BRAF mutation had a tendency to shorter overall survival than those with wild-type KRAS and BRAF (P=0.148), but subgroup analysis demonstrated the patients with KRAS mutations showed worse survival (median, 46.0 months; P=0.046) than those with wild-type KRAS (85.4 months) in lower pT classification (pT1-pT3) group. In summary, KRAS and, infrequently, BRAF mutations are observed in a subset of small intestinal adenocarcinomas, and are associated with higher pT classification and more frequent pancreatic invasion. KRAS mutation is a poor prognostic predictor in patients with lower pT classification tumors. Anti-EGFR targeted therapy could be applied to about two-thirds of small intestinal adenocarcinoma patients, namely those with wild-type KRAS and BRAF if they have metastatic disease, similar to colorectal cancer patients.

Advanced small bowel adenocarcinoma: Molecular characteristics and therapeutic perspectives

Small bowel cancer represents less than 5% of all gastrointestinal cancers, while small bowel adenocarcinoma (SBA) accounts for about one third of all cancers of the small bowel. Although SBA frequently appears sporadically, some diseases are risk factors, such as Crohn's disease and some genetic predispositions to cancer. Progress in the identification of molecular alterations suggests some similarities in carcinogenesis between SBA and colorectal cancer. Evidence levels for the treatment and prognosis of these tumors are insufficient because of the scarcity of this disease and the absence of randomized trials. Chemotherapy based on fluoropyrimidine plus a platinum salt appears to be the most effective treatment regimen in non-randomized prospective trials for advanced SBA. Targeted therapy, against the angiogenic pathway or the epidermal growth factor receptor (EGFR) pathway, for example, is not yet established, but seems promising given the over-expression of vascular epithelial growth factor (VEGF)-A or EGFR observed in SBA. Phase I and II studies are currently evaluating the safety and efficacy of these targeted therapies in SBA treatment. The low incidence of SBA should promote the development of international collaborations to improve our knowledge of the biological mechanisms underlying these tumors and to set up therapeutic trials.

Duodenal adenocarcinoma: Advances in diagnosis and surgical management

Duodenal adenocarcinoma is a rare but aggressive malignancy. Given its rarity, previous studies have traditionally combined duodenal adenocarcinoma (DA) with either other periampullary cancers or small bowel adenocarcinomas, limiting the available data to guide treatment decisions. Nevertheless, management primarily involves complete surgical resection when technically feasible. Surgery may require pancreaticoduodenectomy or segmental duodenal resection; either are acceptable options as long as negative margins are achievable and an adequate lymphadenectomy can be performed. Adjuvant chemotherapy and radiation are important components of multi-modality treatment for patients at high risk of recurrence. Further research would benefit from multi-institutional trials that do not combine DA with other periampullary or small bowel malignancies. The purpose of this article is to perform a comprehensive review of DA with special focus on the surgical management and principles.

Reduction of p53 by knockdown of the UGT1 locus in colon epithelial cells causes an increase in tumorigenesis

BACKGROUND & AIMS

The UDP-glucuronosyltransferases (UGTs) are part of the cells machinery that protects the tissues from a toxicant insult by environmental and host cell metabolites. We have investigated the mechanism behind tumor growth and UGT repression.

METHODS

We initially silenced the Ugt1 locus in human colon cell lines and investigated markers and responses linked to p53 activation. To examine the role of the Ugt1 locus in p53-directed apoptosis and tumorigenesis, experiments were conducted to induce acute colon inflammation and chemical induced colon cancer in mice where we have selectively deleted the Ugt1 locus in the intestinal epithelial cells (Ugt1^ΔIEC mice).

RESULTS

Knockdown of the UGT1A proteins by RNAi in human colon cancer cells and knockout of the Ugt1 locus in intestinal crypt stem cells reduces phosphorylated p53 activation and compromises the ability of p53 to control apoptosis. Targeted deletion of intestinal Ugt1 expression in Ugt1^ΔIEC mice represses colon inflammation-induced p53 production and pro-apoptotic protein activation. When we induced colon cancer, the size and number of the tumors were significantly greater in the Ugt1^ΔIEC mice when compared to wild type mice. Furthermore, analysis of endoplasmic reticulum (ER) stress-related markers indicated that lack of UGT1A expression causes higher ER stress in intestinal epithelial cells and tissue, which may account for the lower expression of p53.

CONCLUSIONS

Our results demonstrate that UGT1A expression is required to maintain and sustain p53 activation in stress-induced colon epithelial cells and has a significant impact on p53-mediated apoptosis and tumor suppression, thus protecting the colon tissue from neoplastic transformation.

Human Epidermal Growth Factor Receptor 2-Positive Duodenal Adenocarcinoma: A Case Report and Review of the Literature

Duodenal adenocarcinoma is a rare malignancy and carries a poor prognosis. The role of adjuvant therapy and the optimal chemotherapy regimen remain largely unclear. Treatment with trastuzumab results in prolonged survival in gastroesophageal cancer if human epidermal growth factor receptor 2 (HER2) is overexpressed or amplified in tumor cells. However, unlike gastric adenocarcinomas, duodenal cancers seem to rarely harbor HER2 amplification or overexpression. We report the case of a patient with HER2-positive stage III duodenal adenocarcinoma who has received adjuvant chemotherapy including trastuzumab.

Prognostic implications of thymidylate synthase gene polymorphisms in patients with advanced small bowel adenocarcinoma treated with first-line fluoropyrimidine-based chemotherapy

Thymidylate synthase (TS) gene polymorphisms such as tandem repeat (TR) polymorphisms and single-nucleotide polymorphisms (SNPs) affect transcriptional efficiency of the TS gene and may be prognostic markers for fluoropyrimidine-based therapy in various gastrointestinal cancers. However, data for TS polymorphisms on clinical outcomes in advanced small bowel adenocarcinoma (SBA) are limited. We retrospectively enrolled 58 locally advanced/metastatic SBA patients treated with first-line fluoropyrimidine-based chemotherapy and analyzed the relationship between TS genotypes and clinical outcomes in 30 patients who were available for tumor tissue. Based on TR polymorphisms and a G>C SNP in the promoter region of the TS gene, 74% of patients had high TS expression genotypes (2R/3RG, 3RG/3RC, 3RG/3RG); the remainder had low TS expression genotypes (2R/2R, 2R/3RC, 3RC/3RC). After a median follow-up of 48.8 months, median progression-free survival (PFS) and overall survival (OS) in all patients were 6.0 and 11.3 months, respectively. However, patients with low TS expression genotypes had better median PFS (12.8 vs. 4.3 months, P=0.027) and OS (28.8 vs. 8.9 months, P=0.025) than those with high TS expression genotypes. In multivariate analysis, poor Eastern Cooperative Oncology Group performance status [hazard ratio (HR), 2.85; 95% CI, 1.02-7.93] and high TS expression genotypes (HR, 3.49; 95% CI, 1.13-10.78) were independent prognostic factors for worse OS. Therefore, TS genotypes, based on a G>C SNP in the TR sequence of the TS gene, may be a useful biomarker for predicting outcomes for fluoropyrimidine-based chemotherapy in patients with locally advanced/metastatic SBA.

[Primary adenocarcinoma of the terminal ileum, synchronous]

BACKGROUND

Among the rarest types of cancer found are the small intestine malignancies, representing only 2% of all gastrointestinal cancer and 0.1-0.3% of all malignancies. The most common subtype of this tumour is the adenocarcinoma, which is located mainly in the duodenum, jejunum and, rarely, in ileum.

CLINICAL CASE

A 75 year-old male, with no any surgical history, who in the previous three months, referred to two clinical episodes of partial bowel obstruction and unquantified weight loss. When admitted into the surgical service, the patient referred to a partial bowel obstruction of more than one week onset. A laparotomy was performed, finding 3 stenosis rings at the ileum end portion, carrying out an intestinal resection and enteral-enteral anastomosis. On the seventh day there was dehiscence of the anastomosis and abdominal sepsis. New surgery was performed with the resection of the intestinal anastomosis and an ileostomy. The pathologist report indicated a small bowel adenocarcinoma moderately differentiated, ulcerated, and multifocal. It was classified as stage III or T3N1M0. The patient progress was satisfactorily, managed as outpatient with postoperative chemotherapy with 5 fluorouracil and cisplatin. The patient died a year later due to liver metastases.

CONCLUSIONS

Due to the extreme rarity of the case, is very likely that general surgeons may find one or two cases of adenocarcinoma of the ileum in their professional career. Thus, they must suspect this pathology when faced with an episode of intestinal obstruction in the adult.

Extra-ampullary duodenal adenocarcinoma

Extra-ampullary duodenal adenocarcinomas are rare, and when studied, frequently have been grouped with jejunoileal adenocarcinomas. Nevertheless, anecdotal experiences suggest that these neoplasms may present 2 or more distinct phenotypes. To better characterize these neoplasms, we performed a retrospective review of 38 cases with a special focus on the morphologic and immunophenotypic characteristics and their clinicopathologic significance. Our cohort of extra-ampullary duodenal adenocarcinomas was classified on the basis of the morphologic features into gastric type (n=19, 50%), intestinal type (n=14, 37%), pancreaticobiliary type (n=2, 5%), and others (n=3, 8%). Most gastric-type adenocarcinomas (n=18, 95%) developed in the proximal duodenum, whereas the other types were located equally in the proximal and distal duodenum. Intestinal-type dysplasia was present at the periphery of 8 (57%) intestinal-type adenocarcinomas, and 8 (42%) gastric-type adenocarcinoma were associated with gastric-type dysplasia. Gastric foveolar metaplasia (n=12) and Brunner gland hyperplasia (n=10) were exclusively recognized adjacent to gastric-type adenocarcinomas. Notably, intestinal-type histology and the absence of lymph node metastasis were significantly associated with favorable disease-free survival in univariate and multivariate analyses. In summary, this study demonstrated that 2 major subsets of extra-ampullary duodenal adenocarcinoma, intestinal type and gastric type, are associated with distinct histopathologic features and clinical behavior.

Characterization of a new small bowel adenocarcinoma cell line and screening of anti-cancer drug against small bowel adenocarcinoma

Small bowel adenocarcinoma (SBA) is a rare, aggressive malignancy with a poor prognosis, and the mechanisms of carcinogenesis in SBA remain unclear. Our aims were to investigate the molecular mechanisms underlying SBA and to identify treatments by establishing and characterizing an SBA cell line and performing anti-cancer drug screening. SIAC1 cells, established from jejunal SBA, showed epithelial characteristics and formed organoids in 3D culture. SIAC1 cells had a heterozygous β-catenin deletion mutation, resulting in a stable β-catenin protein with enhanced Wnt/β-catenin activity. SIAC1 cells lacked MLH1 and MSH6 expression, and target genes such as TGFBR2 and ACVR2 showed frameshift mutations. Among 10 clinical SBA samples, 2 (20%) had interstitial deletions in β-catenin, expression of mismatch repair protein was aberrant in 4 (40%), and heterozygous frameshift mutations of three target genes were found in all 10 samples. On screening assay using 140 compounds, eribulin significantly inhibited SIAC1 cell growth both in vitro and in vivo by inhibition of the Wnt/β-catenin pathway via enhanced degradation of β-catenin. In conclusion, we established an SBA cell line with molecular characteristics similar to those of clinical SBA samples, including β-catenin deletion and mismatch repair protein deficiency, that will be useful for SBA research. Eribulin might be a candidate for SBA treatment due to its inhibitory effect on Wnt/β-catenin signaling.

Primary small-bowel malignancy: update in tumor biology, markers, and management strategies

PURPOSE

Primary small-bowel malignancies (SBM) are rare tumors but their incidence is rising. An estimated 9160 new cases and 1210 deaths due to SBM may occur in the USA in 2014. We review advances made in tumor biology, immunohistochemistry, and discuss treatment strategies for these malignancies.

METHODS

Relevant articles from PubMed/Medline and Embase searches were collected using the phrases "small-bowel adenocarcinoma, gastrointestinal carcinoids, gastrointestinal stromal tumors, small-bowel leiomyosarcoma, and small-bowel lymphoma".

RESULTS

Advances in imaging techniques such as wireless capsule endoscopy, CT and MRI enterography, and endoscopy (balloon enteroscopy) along with discovery of molecular markers such as c-kit and PDGFRA for GIST tumors have improved our ability to diagnose, localize, and treat these patients. Early detection and surgical resection offers the best chance for long-term survival in all tumors except bowel lymphoma where chemotherapy plays the main role. Adjuvant therapy with imatinib has improved overall survival for GIST tumors, somatostatin analogs have improved symptoms and also inhibited tumor growth and stabilized metastatic disease in carcinoid disease, but chemotherapy has not improved survival for adenocarcinoma.

CONCLUSIONS

Recent advances in molecular characterization holds promise in novel targeted therapies. Currently ongoing trials are exploring efficacy of targeted therapies and role of adjuvant therapy for adenocarcinoma and results are awaited. Early detection and aggressive surgical therapy for all localized tumors and lymph node sampling particularly for adenocarcinoma remains the main treatment modality.

Prognostic significance of CDX2 and mucin expression in small intestinal adenocarcinoma

The clinicopathological and prognostic significance of CDX2 and mucin expression have not been comprehensively evaluated in small intestinal adenocarcinoma. Immunohistochemical microarray analyses of CDX2, MUC1, MUC5AC, and MUC6 protein expressions in 189 surgically resected small intestinal adenocarcinoma cases were examined and compared with various clinicopathologic variables, including survival. CDX2, MUC1, MUC5AC, and MUC6 expressions were observed in 43.4% (82 patients), 37.6% (71), 31.7% (60), and 21.7% (41) of patients, respectively. Whereas CDX2 expression was found to be associated with low-grade tumors (P=0.034), fewer nodal metastases (P=0.019), and less perineural invasion (P=0.049) in small intestinal adenocarcinoma patients, patients expressing MUC1 tended to demonstrate high-grade (P=0.021) and nodular or infiltrative (P=0.020) tumors. On the basis of the combined CDX2, MUC1, MUC5AC, and MUC6 expression patterns, small intestinal adenocarcinoma patients were further classified as intestinal (CDX2+/MUC1-; 29.6%), pancreatobiliary (CDX2-/MUC1+; 23.8%), mixed (CDX2+/MUC1+; 13.8%), gastric (CDX2-/MUC1-/MUC5AC+ or MUC6+; 13.8%), or null (CDX2-/MUC1-/MUC5AC-/MUC6-; 19.0%). Among these immunophenotypes, intestinal-type patients demonstrated more frequent distal (jejunal or ileal; P=0.033), tubular (P=0.039), and low-grade tumors (P=0.004) and significantly better survival according to univariate (P<0.0001) and multivariate (P=0.001) analyses. In summary, intestinal immunophenotype adenocarcinomas are associated with distal (jejunal or ileal), tubular, and low-grade tumors and better survival outcomes. Hence, CDX2 and mucin immunohistochemical staining may provide better estimations of survival after surgical resection and intestinal immunophenotype could therefore be used as a better prognostic indicator of small intestinal adenocarcinoma.

The analysis of microsatellite instability in extracolonic gastrointestinal malignancy

Microsatellite instability (MSI) is a genetic feature of sporadic and familial cancers of multiple sites and is related to defective mismatch repair (MMR) protein function. Lynch syndrome (LS) is a familial form of MMR deficiency that may present with a spectrum of MSI positive cancers including gastrointestinal (GI) malignancies. The incidence of high level MSI (MSI-H) in colorectal carcinoma is well defined in both familial and sporadic cases and these tumours portend a better overall prognosis in colorectal carcinoma (CRC). There are certain morphological features that suggest MSI-H CRC and international guidelines have been established for the evaluation of MSI in CRC. The prevalence and morphological features of extracolonic GI MSI-H tumours are less well documented. Furthermore, it is unclear whether the guidelines for the assessment of MSI in CRC are appropriate for application to extracolonic GI malignancies. This review aims to summarise the recent literature on MSI in extracolonic LS-related GI tract malignancies with special attention to the assessment of the MMR system by evaluation of specific microsatellite markers and/or immunohistochemical evaluation of MMR protein expression. The reported prevalence of sporadic and LS-related MSI-H tumours along with their associated unique morphological patterns and related prognostic or therapeutic implications will be discussed.

Complete response and prolonged disease-free survival in a patient with recurrent duodenal adenocarcinoma treated with bevacizumab plus FOLFOX6

Small bowel adenocarcinoma is an uncommon gastrointestinal malignancy with limited data on effective chemotherapy in the adjuvant setting, as well as for advanced disease. We present a case report of a patient with recurrent duodenal adenocarcinoma after resection and adjuvant chemotherapy who experienced a complete response to bevacizumab with oxaliplatin and 5FU (FOLFOX) followed by bevacizumab/capecitabine maintenance therapy for 2 years. The patient continues to be disease-free 8 years after his recurrence. This case highlights the potential of vascular endothelial growth factor (VEGF) inhibitors to enhance chemotherapeutic regimens for advanced small bowel adenocarcinoma.

Small bowel adenocarcinoma: epidemiology, risk factors, diagnosis and treatment

Small bowel adenocarcinomas are rare tumours, but their incidence is increasing. Their most common primary location is the duodenum. The few studies that have collected data regarding small bowel adenocarcinoma are not homogeneous and are widely spread over time. Even though these tumours are most often sporadic, some predisposing diseases have been identified, among which Crohn's disease and genetic syndromes. Early diagnosis of small bowel adenocarcinoma remains difficult despite significant radiological and endoscopic progress. After surgical resection the main prognostic factor is node invasion; in this case, adjuvant chemotherapy can be expected to be beneficial, although this has not been established by randomised trials. For metastatic disease, platinum-based chemotherapy seems to be the most effective treatment. Targeted therapies have not yet been evaluated in this type of cancer.

Molecular diagnostics in the neoplasms of small intestine and appendix

Adenocarcinoma of the small intestine is relatively rare in comparison to colorectal carcinoma. Adenocarcinoma of the small intestine arises through the adenoma-carcinoma sequence in the colon. However, adenocarcinomas arising in the background of inflammatory bowel disease develop through the dysplasia-carcinoma sequence. Most of the cases occur in the duodenum; however, adenocarcinoma occurring in association with Crohn disease is more common in the ileum.

Small bowel adenocarcinoma phenotyping, a clinicobiological prognostic study

BACKGROUND

Small bowel adenocarcinoma (SBA) is a rare tumour with a poor prognosis. Molecular biology data on SBA carcinogenesis are lacking.

METHODS

Expression of HER2, β-catenin, p53 and mismatch repair (MMR) protein was assessed by immunohistochemistry. KRAS, V600E BRAF mutations and microsatellite instability were investigated.

RESULTS

We obtained samples from 63 SBA patients (tumour stages: I-II: 30%; III: 35%; IV: 32%; locally advanced: 3%). HER2 overexpression (3+) was observed in 2 out of 62 patients, overexpression of p53 in 26 out of 62, abnormal expression of β-catenin in 12 out of 61, KRAS mutation in 21 out of 49, BRAF V600E mutation in 1 out of 40 patients, MMR deficiency (dMMR) in 14 out of 61 and was consistent with Lynch syndrome in 9 out of 14 patients. All of the dMMR tumours were in the duodenum or jejunum and only one was stage IV. Median overall survival (OS) was 36.6 months (95% CI, 26.9-72.2). For all patients, in univariate analysis, stages I-II (P<0.001), WHO PS 0-1 (P=0.01) and dMMR phenotype (P=0.02) were significantly associated with longer OS. In multivariate analysis, disease stage (P=0.01) and WHO PS 0-1 (P=0.001) independently predicted longer OS. For stage IV patients, median OS was 20.5 months (95% CI: 14.6; 36.6 months). In multivariate analysis, WHO PS 0-1 (P=0.0001) and mutated KRAS status (P=0.02) independently predicted longer OS.

CONCLUSION

This large study suggests that molecular alterations in SBA are closer to those in colorectal cancer (CRC) than those in gastric cancer, with low levels of HER 2 overexpression and high frequencies of KRAS mutations. The seemingly higher frequency of dMMR than in CRC may be explained by the higher frequency of Lynch syndrome in SBA patients. A dMMR phenotype was significantly associated with a non-metastatic tumour (P=0.02). A trend for a good prognosis and a duodenum or jejunum primary site was associated with dMMR.

Clinicopathologic features and prognosis of duodenal adenocarcinoma and comparison with ampullary and pancreatic ductal adenocarcinoma

Because of the rarity of duodenal adenocarcinoma (DAC), the clinicopathologic features and prognostication data for DAC are limited. There are no published studies directly comparing the prognosis of DAC to that of ampullary adenocarcinoma (AA) and of pancreatic ductal adenocarcinoma (PDA) after resection. In this study, we examined the clinicopathologic features of 68 patients with DAC, 92 patients with AA, and 126 patients with PDA who underwent resection. Patient clinicopathologic and survival information were extracted from medical records. Statistical analysis was performed using Statistical Package for the Social Sciences with 2-sided significance level of .05. Patients with DAC had higher American Joint Committee on Cancer (AJCC) stage than AA patients (P = .001). Lymph node metastasis (P = .013) and AJCC stage (P = .02) correlated with overall survival in DAC patients. Patients with DAC or AA had lower frequencies of lymph node metastasis and positive margin and better survival than those with PDA (P < .05). However, no differences in nodal metastasis, margin status, or survival were observed between DAC patients and those with AA. Our study showed that lymph node metastasis and AJCC stage are important prognostic factors for overall survival in DAC patients. Patients with DAC had less frequent nodal metastasis and better prognosis than those with PDA. There was no significant difference in prognosis between DAC and AA.

Molecular alterations of EGFR in small intestinal adenocarcinoma

BACKGROUND AND AIMS

Molecular testing for epidermal growth factor receptor (EGFR) mutations has recently become a standard practice for the management of patients with non-squamous none small cell lung cancer. Primary small intestine adenocarcinoma (SIA) is an uncommon malignancy, and EGFR mutation in the cancer has not been well characterized due to its rarity.

METHODS

A micro-tissue array with 53 SIAs and 24 surgically resected primary non-ampullary SIAs were studied. EGFR mutations were analyzed by DNA sequencing in 24 cases with formalin-fixed paraffin-embedded blocks. All 77 cases were examined by immunohistochemistry (IHC) using antibodies specific for the EGFR E746-A750 deletion in exon 19 (DEL), L858R point mutation in exon 21 (L858R), and total EGFR. EGFR amplifications were detected by fluorescence in situ hybridization.

RESULTS

A positive reaction of DEL-specific, L858R-specific, and total EGFR antibodies was detected in seven (9.1%), 5 (6.5%) and 35 (45.5%) of 77 SIAs by IHC, respectively. Positive reaction of the three antibodies was not significantly correlated with patient's age, gender, differentiation, and stage. EGFR gene amplification was assayed in 77 SIAs in micro-tissue array. Of 24 SIA samples that had DNA sequencing, two (8.3%) harbored exon 19 deletion and one (4.2%) harbored L858R point mutation. Only one case with EGFR amplification and two cases with polysomy were shown.

CONCLUSIONS

Our findings suggested that mutations and amplification in EGFR genes are minor events, and most of SIAs may be unsuitable to EGFR-TKIs treatment.

Small bowel adenocarcinomas--existing evidence and evolving paradigms

Small bowel cancers account for 3% of all gastrointestinal malignancies and small bowel adenocarcinomas represent a third of all small bowel cancers. Rarity of small bowel adenocarcinomas restricts molecular understanding and presents unique diagnostic and therapeutic challenges. Better cross-sectional imaging techniques and development of enteroscopy and capsule endoscopy have facilitated earlier and more-accurate diagnosis. Surgical resection remains the mainstay of therapy for locoregional disease. In the metastatic setting, fluoropyrimidine and oxaliplatin-based chemotherapy has shown clinical benefit in prospective non-randomized trials. Although frequently grouped under the same therapeutic umbrella as large bowel adenocarcinomas, small bowel adenocarcinomas are distinct clinical and molecular entities. Recent progress in molecular characterization has aided our understanding of the pathogenesis of these tumours and holds potential for prospective development of novel targeted therapies. Multi-institutional collaborative efforts directed towards cogent understanding of tumour biology and designing sensible clinical trials are essential for developing improved therapeutic strategies. In this Review, we endeavour to outline an evidence-based approach to present-day management of small bowel adenocarcinoma, describe contemporary challenges and uncover evolving paradigms in the management of these rare 'orphan' neoplasias.

The effects of chemotherapy on primary small bowel cancer: A retrospective multicenter observational study in Japan

Small bowel cancer is relatively rare among gastrointestinal tract cancers, including esophageal, gastric and colorectal cancers. The majority of cases of small bowel cancer are diagnosed at an advanced stage, resulting in poor outcomes. The clinical effects of chemotherapy on small bowel cancer have been investigated in a limited number of studies from Europe and the USA. However, they have not yet been fully investigated in Asian countries, including Japan. This retrospective multicenter observational study was designed to investigate the efficacy of chemotherapy on small bowel cancer. A questionnaire survey was conducted in 28 hospitals affiliated with the Osaka University Hospital. We retrospectively reviewed the medical records of 61 patients with small bowel cancer (32 patients who were unable to undergo curative resection or had unresectable distant metastases and 29 who underwent curative resection), treated between 1996 and 2009, to evaluate the outcomes and the efficacy of chemotherapy. There was no significant difference in the overall survival between the patients undergoing curative resection with postoperative adjuvant chemotherapy and those without postoperative adjuvant chemotherapy. In patients with non-curative resection or unresectable distant metastases, the response rate to chemotherapy was 31.6% and the overall survival was significantly higher compared to that without chemotherapy (P=0.008). The study results suggested that chemotherapy is effective for Japanese patients with small bowel cancer who cannot undergo curative resection or have unresectable distant metastases.

Demonstration of CDX2 is highly antibody dependant

OBJECTS

CDX2 is a widely used immunohistochemical marker for intestinal differentiation in neoplasms. In the Nordic Immunohistochemical Quality Control external quality assessment scheme, only 45% of the laboratories participating in the CDX2 challenge in 2009 produced sufficient staining. A major cause of insufficient staining results appeared to be less successful primary antibody (Ab) clones. To evaluate the Ab performance in a standardized way, a comparative study was carried out.

MATERIALS AND METHODS

Tissue microarrays containing 309 non-neoplastic tissues and tumor samples with expected high, low, and no CDX2 expression were used. Five Abs were selected for comparison: EPR2764Y concentrated (Conc), EPR2764Y in a ready-to-use format, and DAK-CDX2, AMT28, and CDX2-88, all Conc. The CDX2 stains were scored blindly using the H-score method. Tissue/tumor samples with a maximum H-score of 150 to 300 (on the basis of the staining giving the highest score) were classified as CDX2 high expressors, samples with a maximum H-score of 10 to 149 as low expressors, and samples with a maximum H-score <10 as negative.

RESULTS AND CONCLUSIONS

A total of 106 tumors were CDX2 positive with at least one of the Abs. For 56 high-expressor tumors, the mean H-scores with EPR2764Y Conc, EPR2764Y ready-to-use, DAK-CDX2, AMT28, and CDX2-88 were 262, 236, 234, 167, and 149, respectively, and the percentage of positive tumors 100, 100, 100, 98, and 93, respectively. For 50 low-expressor tumors, the mean H-scores with the same Abs were 59, 26, 28, 7, and 5, respectively, and the percentage of positive tumors 98, 58, 64, 18, and 14, respectively. With EPR2764Y Conc, CDX2 was demonstrated in 5/19 (26%) urothelial carcinomas, 7/64 (11%) lung adenocarcinomas, 5/30 (17%) large cell/sarcomatoid lung carcinomas, and 4/19 (21%) esophagus squamous cell carcinomas. In-house optimized protocols gave for all 4 Conc Abs better staining results than the vendors' recommended protocols. The sensitivity of CDX2 Abs and protocols must be taken into consideration when classifying neoplasms of unknown origin.

Challenging diagnosis of a jejunal adenocarcinoma with ovarian metastasis: report of an unusual case

We report the first documented case of ovarian metastasis from a jejunal primary adenocarcinoma in an Australian patient. The presentation was unusual, initially a suspicious abdominal nodule in the epigastric area, which turned out to be an adenocarcinoma of possible intestinal origin. Gastroscopy and colonoscopy were performed with no suspicious lesion identified. Abdominal and pelvic ultrasound imaging showed a complex pelvic mass suspicious of ovarian cancer. Laparoscopy was performed to exclude possibility of ovarian cancer and small bowel cancer. The ovarian mass showed similar features from the epigastric nodule, again suggestive of intestinal primary. Definitive diagnosis was obtained when the patient represented 2 months later with malignant bowel obstruction requiring palliative resection of the proximal jejunum. This case demonstrates the difficulty in diagnosing ovarian metastasis from a small bowel primary, which has the potential to mimic an ovarian primary tumour clinically, and a large bowel or ovarian primary pathologically.

Loss of S100A14 expression is associated with the progression of adenocarcinomas of the small intestine

OBJECTIVES

Small intestinal adenocarcinoma (SIAC) is an exceedingly rare human malignant tumor, and its association with the S100A14 gene is not known yet. We aimed to investigate the clinicopathological correlations between S100A14 expression and SIAC.

METHODS

Immunohistochemical analyses of S100A14, p21 and p53 were performed using tissue microarray analysis of 175 surgically resected SIACs.

RESULTS

Of 175 SIACs, loss of S100A14 expression was observed in 128 cases (73.1%). Loss of S100A14 expression was associated with lymph node metastasis (p = 0.009) and advanced disease stage (p = 0.013), and was more frequently observed in distal than duodenal tumors (p = 0.043). The majority of SIACs lost p21 expression (93.7%), and significant loss of p21 expression was observed in cancers with high pT stages (pT(3) and pT(4); p = 0.011), lymph node metastasis (p = 0.029) and advanced cancer stage defined by the American Joint Committee on Cancer (p = 0.005). Overexpression of p53 was found in 23.4% of cases. Positive expression of p53 was associated with distally located SIACs (jejunum or ileum; p = 0.006). There was no association between the expression of S100A14 and p21 or p53.

CONCLUSION

Loss of S100A14 in SIAC is common and is associated with higher metastatic potential and advanced clinical stage.

Multicenter retrospective study of 132 patients with unresectable small bowel adenocarcinoma treated with chemotherapy

BACKGROUND

No standard chemotherapy regimen has been established for unresectable or recurrent small bowel adenocarcinoma (SBA).

METHODS

Clinical courses of 132 patients with unresectable or recurrent SBA who received chemotherapy at 41 institutions in Japan were reviewed retrospectively. Patients were classified into five groups according to first-line chemotherapy regimens: fluoropyrimidine monotherapy (group A), fluoropyrimidine-cisplatin (group B), fluoropyrimidine-oxaliplatin (group C), fluoropyrimidine-irinotecan (group D), and other regimens (group E).

RESULTS

The number of patients in each group was as follows: groups A, 60 patients; group B, 17 patients; group C, 22 patients; group D, 11 patients; and group E, 22 patients. Median progression-free survival (PFS) times were as follows: group A, 5.4 months; group B, 3.8 months; group C, 8.2 months; group D, 5.6 months; and group E, 3.4 months. Median overall survival (OS) times were as follows: group A, 13.9 months; group B, 12.6 months; group C, 22.2 months; group D, 9.4 months; and group D, 8.1 months. Patients in group C achieved significantly longer PFS times and substantially (but not significantly) longer OS times than patients in group A. After adjusting for clinical background characteristics, fluoropyrimidine-oxaliplatin therapy was a significant positive prognostic factor for PFS and OS times.

CONCLUSION

The results suggest that fluoropyrimidine-oxaliplatin combination therapy is the most promising first-line chemotherapy regimen for unresectable or recurrent SBA.

A population-based comparison of adenocarcinoma of the large and small intestine: insights into a rare disease

BACKGROUND

Because of its rarity, adenocarcinoma of the small intestine is frequently compared to adenocarcinoma of the colon, although the validity of this comparison is not known.

METHODS

Patients with small and large bowel adenocarcinoma (SBA and LBA) diagnosed between 1988 and 2007 were identified from the Surveillance, Epidemiology, and End Results registry. Age-standardized incidence and mortality rates were determined. Cancer-specific survival (CSS) stratified by stage and by number of assessed lymph nodes was calculated.

RESULTS

A total of 4518 and 261,521 patients with SBA and LBA, respectively, were identified. In comparison to LBA, patients with SBA were younger and presented with disease of higher stage and histologic grade. The age-standardized incidence rates decreased for LBA (-1.24% per year) but increased for SBA (+1.47% per year). Although age-standardized mortality rates decreased for both LBA and SBA, the decreases were more pronounced for LBA. Five-year CSS was worse for resected SBA compared with resected LBA, although this difference diminished when comparing cases having eight or more lymph nodes assessed. The relative reduction in CSS when selecting eight or more lymph nodes was much greater for duodenal as opposed to jejunal/ileal subsite of the small bowel. With nodal selection the absolute difference in CSS between LBA and SBA for stages I, II, and III was 13, 15.9, and 18.5%, respectively.

CONCLUSIONS

Adequate nodal assessment is much less common in SBA than LBA; and it appears that SBA, in particular duodenal adenocarcinoma, is understaged. Even after corrections to minimize the effect of stage migration and inadequate lymph node evaluation, SBA demonstrated distinctly worse CSS than LBA.

Small bowel adenocarcinoma copy number profiles are more closely related to colorectal than to gastric cancers

BACKGROUND

Small bowel adenocarcinoma (SBA) is a rare cancer and consequently, the options for clinical trials are limited. As they are treated according to either a colorectal or a gastric cancer regimen and the molecular biology of a tumor is a pivotal determinant for therapy response, chromosomal copy number aberrations were compared with the colorectal and gastric adenocarcinomas.

MATERIALS AND METHODS

A total of 85 microsatellite stable (MSS) adenocarcinomas from the stomach, colorectum and small bowel were selected from existing array comparative genomic hybridization (aCGH) datasets. We compared the aCGH profiles of the three tumor sites by supervised analysis and hierarchical clustering.

RESULTS

Hierarchical clustering revealed substantial overlap of 27 SBA copy number profiles with matched colorectal adenocarcinomas but less overlap with profiles of gastric adenocarcinomas. DNA copy number aberrations located at chromosomes 1p36.3-p34.3, 4p15.3-q35.2, 9p24.3-p11.1, 13q13.2-q31.3 and 17p13.3-p13.2 were the strongest features discriminating SBAs and colorectal adenocarcinomas from gastric adenocarcinomas.

CONCLUSIONS

We show that MSS SBAs are more similar to colorectal than to gastric cancer, based on the 27 genome-wide DNA copy number profiles that are currently available. These molecular similarities provide added support for treatment of MSS small bowel cancers according to colorectal cancer regimens.

Second-line chemotherapy with fluorouracil, leucovorin, and irinotecan (FOLFIRI regimen) in patients with advanced small bowel adenocarcinoma after failure of first-line platinum-based chemotherapy: a multicenter AGEO study

BACKGROUND

Small bowel adenocarcinoma (SBA) is a rare tumor with poor prognosis. First-line platinum-based chemotherapy is active in patients with advanced SBA, but data regarding second-line chemotherapy are lacking. The aim of this study was to evaluate the efficacy and tolerability of fluorouracil, leucovorin, and irinotecan (FOLFIRI regimen) as second-line chemotherapy in patients with advanced SBA.

METHODS

We analyzed all consecutive patients who received second-line chemotherapy with FOLFIRI among 93 patients with advanced SBA included from 1996 to 2008 in a previous retrospective multicenter study. Progression-free survival (PFS) and overall survival (OS) were estimated from the start of second-line chemotherapy using the Kaplan-Meier method. Cox models were applied for multivariate analyses.

RESULTS

Among 51 patients who received second-line chemotherapy, 28 patients (male, 57%; median age, 54 years; metastatic disease, 96%) were treated with FOLFIRI after progression (n = 24) or limiting toxicity (n = 4) to first-line FOLFOX (n = 19) or LV5FU2-cisplatin (n = 9). Grade 3-4 toxicity was observed in 48% of patients (grade 3-4 neutropenia, 37%). After a median follow-up of 21.5 months, all patients had tumor progression, and 22 patients died. Objective response rate was 20%, and disease control rate was 52%. Median PFS and OS were 3.2 and 10.5 months, respectively. No clinical, biological, or tumor characteristics were associated with PFS or OS by multivariate analysis.

CONCLUSIONS

Second-line chemotherapy with FOLFIRI produced disease control in half of patients with advanced SBA after failure with first-line platinum-based chemotherapy. Nevertheless, the short median PFS warrants the evaluation of other treatments including targeted therapies.

Lack of HER2 overexpression and amplification in small intestinal adenocarcinoma

HER2 overexpression and amplification have been studied as a therapeutic and prognostic target in a number of human cancers, including esophageal, gastric, and colorectal adenocarcinomas. However, HER2 status has not been well investigated in primary small intestinal adenocarcinoma, probably because of its rarity. In this study, we conducted immunohistochemical analysis and fluorescence in situ hybridization (FISH) for HER2 on 49 primary nonampullar small intestinal adenocarcinomas. The results showed a complete lack of HER2 protein expression in 47 cases (96%) by immunohistochemical analysis. Only 2 cases (4%) showed a 1+ staining pattern. No tumors exhibited 2+ or 3+ HER2 immunoreactivity. By FISH, none of the tumors, including those with 1+ HER2 immunoreactivity, exhibited HER2 gene amplification. These observations demonstrate that HER2 protein overexpression and gene amplification are infrequent events, if they occur at all, in small intestinal adenocarcinoma. Thus, routine immunohistochemical and/or FISH testing for HER2 for potential targeted anti-HER2 therapy may not be beneficial for patients with primary small intestinal adenocarcinoma.