Investigations on the significance of the adenoma-carcinoma sequence in the small bowel

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

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

Endoscopic resection of sporadic duodenal adenomas: comparison of endoscopic mucosal resection (EMR) with hybrid endoscopic submucosal dissection (ESD) techniques and the risks of late delayed bleeding

BACKGROUND

Endoscopic resection (ER) of sporadic duodenal adenomas (SDAs) is an alternative treatment strategy to surgical excision but carries substantial risks of bleeding. Endoscopic submucosal dissection (ESD) of SDAs has a high rate of perforation. This study aimed to examine the outcome for ER of SDAs in two large UK centers, both using a novel hybrid endoscopic mucosal resection (EMR) with ESD.

METHODS

Prospective endoscopy databases of ER cases were examined for the period January 2005 to December 2012. Records were analyzed for patient demographics, lesion size and morphology, staging investigations, procedural technique, outcomes, histology, complications, and follow-up assessments.

RESULTS

The study included 34 patients. The mean adenoma size was 25 mm. Of the 34 cases, 21 (62 %) were managed by the traditional snare EMR technique, 12 (35 %) by the hybrid EMR-ESD technique, and 1 by full en bloc ESD. Successful resection was achieved in 33 (97 %) of the 34 cases. En bloc resection and recurrence rates did not differ significantly between the cases treated by EMR and those treated by hybrid EMR-ESD. Three episodes of significant delayed bleeding occurred 1-18 days after the procedure. No perforations or deaths occurred. The risk of delayed bleeding was higher for the lesions 30 mm in diameter or larger than for the lesions smaller than 30 mm (33% vs. 0 %; p = 0.003). The risk of delayed bleeding was not related to the ER technique used (EMR, 9.5 %; ESD/hybrid, 7.7 %; p = 0.855).

CONCLUSIONS

Endoscopic resection is an effective treatment for SDAs and can avoid the need for open surgery. This is the first series to report the use of a hybrid EMR-ESD technique for the treatment of SDAs in a Western setting. However, this technique did not confer any major outcome benefits over EMR. The risk of delayed bleeding is substantial, and bleeding may occur up to 18 days after the procedure. The risk of delayed bleeding was increased with lesions larger than 30 mm but was not influenced by the endoscopic technique.

Efficacy and safety of endoscopic treatment for nonampullary sporadic duodenal adenomas

BACKGROUND

Nonampullary sporadic duodenal adenomas (NSDAs) are uncommon mucosal neoplasms with malignant potential. Recently, endoscopic treatment is used for NSDA with increasing frequency.

AIMS

This study therefore aimed to evaluate the efficacy and safety of endoscopic treatment for NSDA.

METHODS

A total of 36 NSDAs in 35 consecutive patients were endoscopically eradicated at Samsung Medical Center between October 1994 and May 2011. Data on patient demographics, tumor characteristics, and endoscopic treatment outcomes were obtained and retrospectively analyzed.

RESULTS

Of all patients, 19 (52.8 %) were male. The mean age was 56.0 ± 12.2 (SD) years. Of the 36 NSDAs, 23 lesions were removed by endoscopic resection (ER) including endoscopic mucosal resection (EMR, n = 20) and snare polypectomy (n = 3). In the 23 cases treated with ER, en bloc resection was achieved in 20 (87.0 %). All cases undergoing en bloc resection showed tumor-free resection margins. Thirteen lesions were ablated by argon plasma coagulation (APC). During EMR, bleeding occurred in two cases and perforation occurred in one case. One patient bled during APC. All complications were successfully managed with endoscopic treatment without surgical intervention. During a median follow-up period of 11.4 months (range, 1.8-182.4 months), local recurrence occurred in one patient treated with APC (1/10, 10.0 %). Among patients undergoing ER, no local recurrence occurred but one patient treated with EMR experienced metachronous recurrence.

CONCLUSIONS

Endoscopic treatment, including EMR, snare polypectomy, and APC, was an effective and safe treatment for NSDA. Further multi-center large prospective studies are warranted to establish appropriate treatment guidelines for NSDA.

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.

A large prospective study of risk factors for adenocarcinomas and malignant carcinoid tumors of the small intestine

PURPOSE

Small intestinal cancer is increasing in the U.S.A, yet little is known about its etiology. Our aim was to prospectively evaluate risk factors for this malignancy by the two main histologic subtypes (adenocarcinomas and carcinoids).

METHODS

Hazard ratios and 95% confidence intervals (CI) were estimated for all incident small intestinal cancers (n = 237), adenocarcinomas (n = 84), and malignant carcinoids (n = 124), by demographic and lifestyle factors among 498,376 men and women.

RESULTS

Age was the only risk factor for adenocarcinomas (HR for ≥ 65 vs. 50-55 years = 3.12, 95% CI 1.33, 7.31). Age (HR for ≥ 65 vs. 50-55 years = 3.31, 95% CI 1.51, 7.28), male sex (HR = 1.44, 95% CI 1.01, 2.05), body mass index (BMI, HR for ≥ 35 vs. 18.5-< 25 kg/m2 = 1.95, 95% CI 1.06, 3.58), and current menopausal hormone therapy use (HR = 1.94, 95% CI 1.07, 3.50) were positively associated with malignant carcinoids. A family history of any cancer or colorectal cancer (HR = 1.42, 95% CI 0.99, 2.03; 1.61, 0.97, 2.65, respectively), or a personal history of colorectal polyps (HR = 1.51, 95% CI 0.92, 2.46) produced elevated, but not statistically significant, risks for malignant carcinoids. Race, education, diabetes, smoking, physical activity, and alcohol intake were not associated with either histologic subtype.

CONCLUSIONS

Risk factors differed according to cancer subtype; only age was associated with adenocarcinomas, whereas age, male sex, BMI, and menopausal hormone therapy use were positively associated with malignant carcinoids.

"Underwater" EMR of sporadic laterally spreading nonampullary duodenal adenomas (with video)

BACKGROUND

EMR for the treatment of duodenal adenomas is challenging due to a thin wall and rich vascularity.

OBJECTIVE

To evaluate a novel technique of "underwater" EMR without prior submucosal injection for the removal of large (≥2 cm) laterally spreading nonampullary duodenal adenomas.

DESIGN

Prospective, observational study.

SETTING

Tertiary academic referral center.

PATIENTS

Twelve patients (median age, 60 years) meeting the inclusion criteria.

INTERVENTIONS

Piecemeal EMR technique after sterile water submersion when using a double-channel endoscope.

MAIN OUTCOME MEASUREMENTS

Technical success, adverse events, completeness of resection on follow-up endoscopy.

RESULTS

Median adenoma size was 35 mm (25% greater than one-half circumference, 50% equal to one-third to one-half circumference, and 25% less than one-third circumference). Median procedure time was 65 minutes (range, 32-151). Final histology was tubular adenoma (7), tubulovillous adenoma (1), villous adenoma (3), and high-grade dysplasia (1). Eleven patients (92%) met the primary endpoint (technical success) and all patients met the secondary endpoint (completeness of resection). Median interval until follow-up endoscopy was 16 weeks (range, 11-56). Adverse events were as follows: delayed bleeding (3 patients, of whom 2 required transfusions), water intoxication syndrome manifested by altered mental status and hyponatremia (1), and stricture formation (1) that responded to balloon dilation. No perforation or postresection abdominal pain was found.

LIMITATIONS

Single operator, single center, small sample size, limited follow-up.

CONCLUSION

Underwater EMR for large sessile duodenal adenomas has high success rates for complete removal. The risk of delayed bleeding is significant, and precautions are needed when infusing a large volume of fluid into the GI tract.

Familial risk of small intestinal carcinoid and adenocarcinoma

BACKGROUND & AIMS

Small intestinal cancer (SIC) is rare, and its etiology is poorly understood. We compared clusters of families with SICs of different histologic subtypes.

METHODS

By using the nationwide family cancer data sets of Sweden and Finland, we identified a cohort of 9964 first-degree relatives of 1799 patients with SIC, diagnosed from 1961 through 2009. Data were collected from time periods as long as 47 years (mean, 35.4 y), and cancer incidence was determined. Standardized incidence ratios (SIRs) were calculated and stratified by sex, age, time period, and cancer type, using the incidence rates for the entire national population as the reference.

RESULTS

Among the 1799 SIC cases, 1.1% had a sibling with SIC, so the SIR was 11.8 (95% confidence interval [CI], 7.2-18.2); 1.1% had a parent or child with SIC (SIR, 3.5; 95% CI, 2.0-5.6). The SIR of concordant carcinoid histology of SIC among siblings was 28.4 (95% CI, 14.7-49.6; n = 12) and in parent-child pairs was 9.9 (95% CI, 5.4-16.6; n = 14). The familial risk of concordant histologic subtypes increased for siblings diagnosed with adenocarcinoma, but only 2 familial cases were identified. In family members of patients with SIC of the adenocarcinoma subtype, risks of colorectal and bladder cancer were modestly but significantly increased compared with the general population. Family members of patients with SIC of the carcinoid subtype had an increased risk for kidney cancer and polycythemia vera.

CONCLUSIONS

Based on data from our population-based study, first-degree relatives of patients with small intestinal carcinoid tumors have developed these tumors with high incidence. Because of the rareness of this tumor, the absolute risk remains moderate even within families. Gastroenterologists could inform patients with small intestinal carcinoids about the familial risk and encourage counseling for their first-degree relatives. Studies are needed to identify genetic factors that affect susceptibility to SIC.

Jejunal tubulovillous adenocarcinoma in adenoma presenting with entero-enteric intussusception

A 73-year-old male was admitted to our institution with complaints of nausea, vomiting, and abdominal distension. Plain abdominal computed tomography (CT) suggested intussusception in the jejunum. Enhanced abdominal CT revealed the 'target-like' sign and ultrasonography revealed the 'multiple concentric ring' sign; therefore, a diagnosis of entero-enteric intussusception was made. The small intestinal obstruction and cause of the intussusception were not evident. The patient was treated conservatively with fasting and transfusion therapy to prevent intestinal obstruction. However, with no spontaneous resolution of intussusception, surgical treatment was decided. The operative findings revealed a jejunal tumor about 30 cm from the Treiz ligament, and the jejunum including the tumor with a 5 cm margin were partially resected. The resected tumor was a 35 × 50 mm soft mass spreading laterally with nodules. The pathological examinations revealed tubulovillous adenocarcinoma in the adenoma. Intussusception is rare in adults compared to children. About 45 % of cases of intussusception in adults are due to small intestinal tumors such as malignant lymphoma or lipoma, but a tubulovillous adenocarcinoma with adenoma is a rare cause of intussusception. We present a rare case of jejunal tubulovillous adenocarcinoma in adenoma presenting with entero-enteric intussusception.

Cap-assisted EMR of large, sporadic, nonampullary duodenal polyps

BACKGROUND

EMR is an effective alternative to surgery for the removal of nonampullary duodenal polyps (NADPs). Cap-assisted EMR (EMR-C) has been rarely performed in the duodenum because of the risk of perforation.

OBJECTIVE

To evaluate the safety and effectiveness of EMR-C for the removal of large (≥ 15 mm) NADPs.

DESIGN

Retrospective study.

SETTING

Tertiary-care referral center.

PATIENTS

Between 2000 and 2010, 26 consecutive patients with sporadic NADPs underwent EMR-C.

INTERVENTION

EMR with the cap technique.

MAIN OUTCOME MEASUREMENTS

Complete eradication of polyps, complications, and recurrence.

RESULTS

A total of 14 sessile polyps (53.8%), 7 lateral spreading type nongranular tumors (26.9%), and 5 lateral spreading type granular tumors (19.2%) were treated. The median size of lesions was 15 mm. Five lesions involved one-half of the luminal circumference. Post-EMR histologic assessment showed low-grade dysplasia in 5 patients (19.2%) and high-grade dysplasia in 18 patients (69.2%). Three patients (11.5%) had well-differentiated endocrine tumors. Complete eradication was obtained in 25 of 26 (96%) patients. No perforations occurred. Three cases of intraprocedural bleeding were managed endoscopically. Median follow-up was 6 years (range 1-10 years). Residual adenomatous tissue was observed in 3 patients in lesions of 50 mm. In one of these cases, an adenocarcinoma occurred after 8 months, which was managed surgically.

LIMITATIONS

Retrospective design, single center.

CONCLUSION

This study supports the efficacy and safety of EMR-C for removing NADPs. Regular follow-up is mandatory because of the high risk of residual or recurrent adenomatous tissue and even cancer.

Small bowel adenocarcinoma - report of two cases and review of literature

Although accounting for 90 % of the intestinal surface area, small bowel adenocarcinomas are not common. The majority of these lesions are incidentally detected during laparotomy for intestinal obstruction or perforation. The symptoms associated with these lesions are not very specific and preoperative diagnosis is rare. We report two cases of jejunal adenocarcinomas detected in patients undergoing laparotomy for acute abdomen and review the literature for small bowel adenocarcinomas.

Small bowel endoscopy in familial adenomatous polyposis and Lynch syndrome

Patients with familial adenomatous polyposis (FAP) and patients with Lynch syndrome have an increased risk of developing small intestinal neoplasia. In both conditions, the lifetime risk to develop small bowel cancer is estimated to be around 5%. In FAP, this risk is associated with the degree of duodenal polyposis, classically assessed by the Spigelman classification. For this reason, gastroduodenal surveillance with forward-viewing and side-viewing endoscopy is generally recommended. Studies using video capsule endoscopy and balloon-assisted enteroscopy in FAP patients have revealed that jejunal and ileal polyps occur frequently in FAP, especially in those with extensive duodenal polyposis. Nevertheless, the clinical relevance of small bowel polyps beyond the duodenum appears to be limited. Compared to FAP, little is known about the prevalence and natural history of small bowel neoplasia in Lynch syndrome. Surveillance of the small bowel is not recommended in Lynch syndrome, although recent data using capsule endoscopy provided promising results.

Management of sporadic duodenal adenomas and the association with colorectal neoplasms: a retrospective cohort study

GOALS

To evaluate management, outcome, and follow-up of patients with sporadic duodenal adenomas and assess the presence of colorectal neoplasms.

BACKGROUND

With the widespread use of esophagogastroduodenoscopy, an increasing number of sporadic duodenal adenomas are diagnosed. An optimal algorithm for management has not been fully defined. Accumulating data suggest an association with colorectal neoplasms.

STUDY

Patients diagnosed with sporadic duodenal adenomas at our institute from 1986 until 2008 were retrospectively reviewed. Data were collected from medical records.

RESULTS

Fifty-four patients (28 men, 52%) were diagnosed with a sporadic duodenal adenoma at a median age of 59 years (range, 27 to 84 y); 33 patients (61%) underwent endoscopic or surgical intervention, 5 (9%) were only followed endoscopically, and 16 (30%) underwent no intervention or follow-up. Complete endoscopic removal was accomplished in at least 81% of cases, and no complications were reported; surgical intervention was complicated in 4 patients, with 1 resulting in death. Adenoma recurrence was 20% at a median follow-up of 18 months (range, 4 to 54 mo), but no carcinoma developed. Colorectal neoplasms were found in 16 of 29 patients (55%) who underwent colonoscopy, including 2 cancers (7%), 7 advanced adenomas (24%), and 7 nonadvanced adenomas (24%).

CONCLUSIONS

Although no consistent approach to management of sporadic duodenal adenomas was followed, no duodenal carcinoma developed during the follow-up. Endoscopic intervention is preferred over surgical intervention, whenever possible. Once complete removal is ascertained, there is no strict indication for regular follow-up esophagogastroduodenoscopy, especially in elderly patients or patients with relevant comorbidity. Colonoscopic assessment is warranted in all patients diagnosed with sporadic duodenal adenomas.

Endoscopic management of nonampullary duodenal polyps

Duodenal polyps are a rare finding in patients presenting for gastroscopy, being found in 0.3-4.6% of cases. The majority of patients are asymptomatic. The most common lesions necessitating removal are duodenal adenomas which should be differentiated from other mucosal lesions such as ectopic gastric mucosa, and submucosal lesions such as carcinoids and gastrointestinal stromal tumours (GISTs). Adenomas can occur sporadically or as part of a polyposis syndrome. Both groups carry malignant potential but this is higher in patients with a polyposis syndrome. The majority of sporadic duodenal adenomas are flat or sessile and occur in the second part of the duodenum. Historically duodenal adenomas have been managed by radical surgery, which carried significant mortality and morbidity, or more conservative local surgical excision which resulted in high local recurrence rates. There is growing evidence for the use of endoscopic mucosal resection (EMR) techniques for treatment of sporadic nonampullary duodenal adenomas, with good outcomes and low complication rates. Endoscopic submucosal dissection (ESD) carries greater risk of complications and should be reserved for experts in this technique. Patients with sporadic duodenal adenomas carry an increased risk of colonic neoplasia and should be offered colonoscopy. The impact of endoscopic resection on the course of polyposis syndromes such as familial adenomatous polyposis (FAP) needs further study.

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.

Pancreaticoduodenectomy for advanced duodenal and ampullary adenomatosis in familial adenomatous polyposis

BACKGROUND

Patients with familial adenomatous polyposis (FAP) develop duodenal and ampullary polyps that may progress to malignancy via the adenoma-carcinoma sequence.

OBJECTIVE

The aim of this study was to review a large series of FAP patients undergoing pancreaticoduodenectomy for advanced duodenal and ampullary polyposis.

METHODS

A retrospective case notes review of all FAP patients undergoing pancreaticoduodenectomy for advanced duodenal and ampullary adenomatosis was performed.

RESULTS

Between October 1993 and January 2010, 38 FAP patients underwent pancreaticoduodenectomy for advanced duodenal and ampullary polyps. Complications occurred in 29 patients and perioperative mortality in two. Postoperative histology revealed five patients to have preoperatively undetected cancer (R = 0.518, P < 0.001).

CONCLUSIONS

Pancreaticoduodenectomy in FAP is associated with significant morbidity, but low mortality. All patients under consideration for operative intervention require careful preoperative counselling and optimization.

Epidemiology of cancer of the small intestine

Cancer of the small intestine is very uncommon. There are 4 main histological subtypes: adenocarcinomas, carcinoid tumors, lymphoma and sarcoma. The incidence of small intestine cancer has increased over the past several decades with a four-fold increase for carcinoid tumors, less dramatic rises for adenocarcinoma and lymphoma and stable sarcoma rates. Very little is known about its etiology. An increased risk has been noted for individuals with Crohn’s disease, celiac disease, adenoma, familial adenomatous polyposis and Peutz-Jeghers syndrome. Several behavioral risk factors including consumption of red or smoked meat, saturated fat, obesity and smoking have been suggested. The prognosis for carcinomas of the small intestine cancer is poor (5 years relative survival < 30%), better for lymphomas and sarcomas, and best for carcinoid tumors. There has been no significant change in long-term survival rates for any of the 4 histological subtypes. Currently, with the possible exceptions of obesity and cigarette smoking, there are no established modifiable risk factors which might provide the foundation for a prevention program aimed at reducing the incidence and mortality of cancers of the small intestine. More research with better quality and sufficient statistical power is needed to get better understanding of the etiology and biology of this cancer. In addition, more studies should be done to assess not only exposures of interest, but also host susceptibility.

Small Bowel Adenocarcinoma in a Patient with Coeliac Disease: Case Report and Review of the Literature

Coeliac disease (CD) is an autoimmune disorder which leads to chronic inflammation of the gut. Furthermore, CD is associated with upper gastrointestinal malignancies, particularly lymphoma of the small intestine. Besides lymphoma, an increased frequency of associated small bowel carcinoma has been described. Here we report the case of a 70-year-old male suffering from CD who was treated with a gluten-free diet presenting with complaints of nausea, vomiting and weight loss of about 8 kg in two months. He underwent esophagogastroduodenoscopy, which identified distention of the stomach and duodenum and in the pars horizontalis a distinct obstruction was suggestive. However, histopathological examination showed a normal mucosal membrane. Additionally, a computed tomography scan of the abdomen was performed which showed an expanded stomach and duodenum up to the ligament of Treitz. During an explorative laparotomy a small tumor was palpated near the ligament of Treitz. Subsequently, a duodenal segment resection was performed. After surgery, the patient recovered well and left our hospital in good condition.

Efficacy and long-term outcome of endoscopic treatment of sporadic nonampullary duodenal adenoma

BACKGROUND/AIMS

Endoscopic resection has proven to be a safe and effective alternative to surgery for duodenal adenomas. However, few data are available on the adequacy of resection and long-term outcomes. This study evaluated the efficacy and longterm endoscopic findings in a cohort of Korean patients who underwent endoscopic mucosal resection (EMR) of sporadic duodenal adenomas.

METHODS

Seventeen patients with nonampullary duodenal adenomas without familial polyposis syndrome and who were treated by EMR between January 2001 and December 2007 were evaluated retrospectively. Their management, follow-up, and outcomes were reviewed.

RESULTS

In total, seventeen lesions were removed from EMR in 17 patients (mean age, 59.3 years; 6 women, 11 men). The mean size of the tumors was 15.1 mm (median, 13 mm, range, 8-27 mm). Of these 17 adenomas, 16 adenomas were tubulous and 1 was tubulovillous. The EMR was performed successfully in all 17 patients in a single session. After a median follow-up period of 29 months (range, 13-72 months), all patients remained in remission. One patient had bleeding at the site of the EMR. There were no perforations after the EMR.

CONCLUSIONS

EMR for sporadic duodenal adenomas seemed to be a safe and effective treatment modality.

Adenocarcinoma of the small intestine: a multi-institutional study of 197 surgically resected cases

Small intestinal adenocarcinoma is a rare malignant neoplasm, and its clinicopathologic characteristics have not been well elucidated. A total of 197 small intestinal adenocarcinoma cases were collected from 22 institutions in South Korea and were evaluated for clinicopathologic factors that affect the prognosis of small intestinal adenocarcinoma patients using univariate and multivariate analyses. The mean patient age was 59 years, and the male-to-female ratio was 1.7:1. Tumors were located in the duodenum of 108 cases (55%), the jejunum in 59 (30%), and the ileum in 30 (15%). Predisposing conditions were observed in 23 cases (12%), including 17 cases with sporadic adenomas, 3 with Peutz-Jeghers syndrome, 2 with Meckel diverticulum, and 1 with Crohn disease. Synchronous or metachronous malignant tumors were identified in 31 cases (16%), including 13 colorectal and 10 stomach cancers. About 90% of tumors were classified as either pT3 (63 cases) or pT4 (112 cases). The median survival time for all small intestinal adenocarcinoma patients was 39.7 months. Compared with small intestinal adenocarcinomas without accompanying sporadic adenomas, small intestinal adenocarcinomas with accompanying adenomas were more well differentiated (P < .0001), with a more polypoid growth pattern (P < .0001), a lower pT classification (P < .0001), less perineural invasion (P = .01), and less lymphatic invasion (P = .03). Small intestinal adenocarcinoma patients with associated sporadic adenomas (77%) had a significantly better 5-year survival rate than those without sporadic adenomas (38%, P = .02). By univariate analysis, small intestinal adenocarcinoma patients had significantly different survival based on pT classification (P = .003), lymph node metastasis (P < .0001), distal location (jejunal and ileal carcinomas) (P = .003), retroperitoneal tumor seeding (P < .0001), vascular invasion (P = .007), lymphatic invasion (P = .001), peritumoral dysplasia (P = .004), and radiation therapy (P = .006). By multivariate analysis, lymph node metastasis (P = .01) and distal location (P = .003) were independent predictors of a worse prognosis. In conclusion, (1) small intestinal adenocarcinomas are diagnosed at an advanced disease stage; therefore, the development of strategies for detection at an earlier stage is needed. (2) Small intestinal adenocarcinoma patients with an adenomatous component had a better survival than those without an adenomatous component. (3) Lymph node metastasis and distal location (jejunum and ileum) of tumor are the most important independent prognostic factors.

High-resolution array comparative genomic hybridization in sporadic and celiac disease-related small bowel adenocarcinomas

PURPOSE

The molecular pathogenesis of small intestinal adenocarcinomas is not well understood. Understanding the molecular characteristics of small bowel adenocarcinoma may lead to more effective patient treatment.

EXPERIMENTAL DESIGN

Forty-eight small bowel adenocarcinomas (33 non-celiac disease related and 15 celiac disease related) were characterized for chromosomal aberrations by high-resolution array comparative hybridization, microsatellite instability, and APC promoter methylation and mutation status. Findings were compared with clinicopathologic and survival data. Furthermore, molecular alterations were compared between celiac disease-related and non-celiac disease-related small bowel adenocarcinomas.

RESULTS

DNA copy number changes were observed in 77% small bowel adenocarcinomas. The most frequent DNA copy number changes found were gains on 5p15.33-5p12, 7p22.3-7q11.21, 7q21.2-7q21.3, 7q22.1-7q34, 7q36.1, 7q36.3, 8q11.21-8q24.3, 9q34.11-9q34.3, 13q11-13q34, 16p13.3, 16p11.2, 19q13.2, and 20p13-20q13.33, and losses on 4p13-4q35.2, 5q15-5q21.1, and 21p11.2-21q22.11. Seven highly amplified regions were identified on 6p21.1, 7q21.1, 8p23.1, 11p13, 16p11.2, 17q12-q21.1, and 19q13.2. Celiac disease-related and non-celiac disease-related small bowel adenocarcinomas displayed similar chromosomal aberrations. Promoter hypermethylation of the APC gene was found in 48% non-celiac disease-related and 73% celiac disease-related small bowel adenocarcinomas. No nonsense mutations were found. Thirty-three percent of non-celiac disease-related small bowel adenocarcinomas showed microsatellite instability, whereas 67% of celiac disease-related small bowel adenocarcinomas were microsatellite unstable.

CONCLUSIONS

Our study characterized chromosomal aberrations and amplifications involved in small bowel adenocarcinoma. At the chromosomal level, celiac disease-related and non-celiac disease-related small bowel adenocarcinomas did not differ. A defect in the mismatch repair pathways seems to be more common in celiac disease-related than in non-celiac disease-related small bowel adenocarcinomas. In contrast to colon and gastric cancers, no APC nonsense mutations were found in small bowel adenocarcinoma. However, APC promoter methylation seems to be a common event in celiac disease-related small bowel adenocarcinoma. Clin Cancer Res; 16(5); 1391-401.

Loss of carbamoyl phosphate synthetase I in small-intestinal adenocarcinoma

Carbamoyl phosphate synthetase I (CPS1), normally found in hepatocytes and small-intestine (SI) enterocytes, is the antigen of Hep Par 1 antibody. Expression of CPS1 in invasive SI adenocarcinoma seems to be lost. We retrospectively collected 36 total specimens, which included 31 SI adenomas and 21 adenocarcinomas. We used 34 cases of duodenitis as a control group. Immunohistochemical and Western blot analyses were performed to determine CPS1 expression. The normal SI mucosa, all 34 cases of duodenitis, and all 29 adenomas with low-grade dysplasia demonstrated diffuse Hep Par 1 expression. Of the 21 invasive adenocarcinomas, 15 lost antigen expression (71%). These data are statistically significant (P < .05). Western blot analysis confirmed the immunohistochemical findings, with strong CPS1 expression within the normal mucosa and adenoma and complete loss in the invasive tumor. The differential expression of Hep Par 1 in dysplastic vs malignant tumors of the SI may be diagnostically useful in difficult cases.

Small bowel tumors

Although rare, small bowel tumors may cause significant morbidity and mortality if left undetected. New endoscopic modalities allow full examination of the small bowel with improved diagnosis. However, isolated mass lesions may be missed by capsule endoscopy or incomplete balloon-assisted enteroscopy. Therefore the use of radiologic imaging and intraoperative enteroscopy for diagnosis should not be forgotten. Endoscopic resection of small bowel polyps and certain vascular tumors is possible but requires proper training. Advances in endoscopic tools are likely to broaden the endoscopic management of small bowel tumors. This article describes the general features of small bowel tumors, clinical presentation, and diagnostic tests followed by a description of the more common tumor types and their management.

Enteroscopy and its relationship to radiological small bowel imaging

The field of radiological small bowel imaging is changing rapidly, as is small bowel enteroscopy. New techniques allow the depiction of intraluminal, mural, and extraintestinal features of various small bowel disorders, such as Crohn disease, small bowel polyposis syndromes, small intestinal malignancies, and celiac disease. For patients requiring repeated small bowel imaging, modalities that do not use ionizing radiation, such as ultrasound or magnetic resonance imaging, should be considered.

Increased prevalance of colorectal adenoma in patients with sporadic duodenal adenoma

OBJECTIVES

Duodenal adenomas are common in familial adenomatous polyposis (FAP). It is, however, not known whether patients with duodenal adenomas without FAP should undergo routine colonoscopy for detection of colorectal neoplasia. The aim of this study was to evaluate the correlation between the incidence of sporadic duodenal adenomas and colorectal neoplasias.

METHODS

Patients with sporadic duodenal adenomas and without FAP were retrospectively evaluated for the existence of colorectal neoplasia. Each patient was compared with three randomly selected age and sex-matched controls.

RESULTS

Sporadic duodenal adenomas were diagnosed by endoscopy in 51 patients, of whom 48 underwent additional colonoscopy. The mean age of the 48 analysed patients was 66 (40-83) years (women:men=23 : 25). Colorectal neoplasia was significantly more common among patients with duodenal adenomas (75% vs. 27.7%; P<0.05; odds ratio=7.80 [95% confidence interval 3.48-17.72]).

CONCLUSION

In this case control study, the prevalence of colorectal adenomas in patients with sporadic duodenal adenomas without FAP was significantly increased compared with the average population. Therefore, patients with duodenal adenomas should be screened for the occurrence of colorectal adenomas.

The epidemiology and pathogenesis of neoplasia in the small intestine

PURPOSE

The mucosa of the small intestine encompasses about 90% of the luminal surface area of the digestive system, but only 2% of the total annual gastrointestinal cancer incidence in the United States.

METHODS

The remarkable contrast in age-standardized cancer incidence between the small and large intestine has been reviewed with respect to the cell type patterns, demographic features, and molecular characteristics of neoplasms.

RESULTS

Particularly noteworthy is the predominance of adenocarcinoma in the colon, which exceeds 98% of the total incidence by cell type, in contrast to that of 30% to 40% in the small intestine, resulting in an age-standardized ratio of rates exceeding 50-fold. The prevalence of adenomas and carcinomas is most prominent in the duodenum and proximal jejunum. The positive correlation in global incidence rates of small and large intestinal neoplasms and the reciprocal increases in risk of second primary adenocarcinomas suggest that there are common environmental risk factors. The pathophysiology of Crohn inflammatory bowel disease and the elevated risk of adenocarcinoma demonstrate the significance of the impaired integrity of the mucosal barrier and of aberrant immune responses to luminal indigenous and potentially pathogenic microorganisms.

CONCLUSION

In advancing a putative mechanism for the contrasting mucosal susceptibilities of the small and large intestine, substantial differences are underscored in the diverse taxonomy, concentration and metabolic activity of anaerobic organisms, rate of intestinal transit, changing pH, and the enterohepatic recycling and metabolism of bile acids. Experimental and epidemiologic studies are cited that suggest that the changing microecology, particularly in the colon, is associated with enhanced metabolic activation of ingested and endogenously formed procarcinogenic substrates.

Expression of CD24, P-cadherin and S100A4 in tumors of the ampulla of Vater

Carcinomas of the Vaterian system are rare and presumably arise from preexisting adenomas (adenoma-carcinoma-sequence). Usually, biopsies are obtained to confirm and specify endoscopic findings, but differentiating reactive atypia from dysplasia or dysplasia from invasive carcinoma can sometimes be difficult or even impossible on morphological criteria alone. In case of invasive carcinoma, furthermore, the precise classification of carcinoma subtypes needs to be established since the distinct subtypes differ significantly in terms of clinical outcome. The cell adhesion proteins CD24, P-cadherin and S100A4 were shown to be expressed in several carcinomas and in dysplastic epithelium but only rarely in normal mucosa. We therefore investigated their expression in 177 carcinoma, 114 adenoma and 152 normal mucosa specimens of the ampulla of Vater. Although the expression of the cell adhesion proteins did not differ between the carcinoma subtypes, marked differences between normal mucosa, adenoma and carcinoma samples were observed. All marker proteins were expressed in less than 7% of normal mucosa samples (S100A4 in only 1% of cases) and showed an increasing expression from adenoma to invasive carcinoma. Our findings suggest that P-cadherin and S100A4 are helpful in discriminating normal mucosa or reactive atypia from neoplastic lesions. CD24 and S100A4, furthermore, can assist in the differential diagnosis of dysplasia vs invasive carcinoma.

A prospective study of meat and fat intake in relation to small intestinal cancer

Diets high in red and processed meats are associated with carcinogenesis of the large intestine, but no prospective study has examined meat and fat intake in relation to cancer of the small intestine. We prospectively investigated meat and fat intakes, estimated from a food frequency questionnaire, in relation to small intestinal cancer among half a million men and women enrolled in the NIH-AARP Diet and Health Study. We used Cox proportional hazards regression to estimate hazard ratios (HR) and 95% confidence intervals (95% CI). During up to 8 years of follow-up, 60 adenocarcinomas and 80 carcinoid tumors of the small intestine were diagnosed. Despite slightly elevated HRs for red meat, there were no clear associations for red or processed meat intake and either adenocarcinoma or carcinoid tumors of the small intestine. In contrast, we noted a markedly elevated risk for carcinoid tumors of the small intestine with saturated fat intake in both the categorical (highest versus lowest tertile: HR, 3.18; 95% CI, 1.62-6.25) and continuous data (HR, 3.72; 95% CI, 1.79-7.74 for each 10-g increase in intake per 1,000 kcal). Our findings suggest that the positive associations for meat intake reported in previous case-control studies may partly be explained by saturated fat intake.

Primary adenocarcinoma of the small intestine: presentation, prognostic factors and clinical outcome

BACKGROUND

Malignant small intestine tumor accounts for 0.1-0.3% of all malignancies. Although primary adenocarcinoma is the most common histologic subtype, there is no report of the clinical characteristics and natural history in the Asian population.

METHODS

We conducted retrospective analysis for the patients with the small intestine adenocarcinoma to explore the clinical characteristics and prognosis. All patients with adenocarcinoma of small intestine diagnosed between March 1997 and March 2007 in the Catholic Medical Center in Korea were identified through the cancer registry. The medical records were reviewed for patient characteristics, treatment and outcome data.

RESULTS

Data on 53 patients were available. Twenty-six patients (49.0%) underwent curative resection and 13 patients receiving adjuvant chemotherapy. Fifteen patients received palliative chemotherapy. Median of overall survival of all patients was 12 months (95% confidence interval (CI): 8.5-15.1 months). Three-year survival and relapse-free survival rates after curative resection was 66.1 and 50.8%, respectively. Median survival of patients received palliative chemotherapy was 8.0 months (95% CI: 3.5-12.4).

CONCLUSIONS

The prognosis of primary adenocarcinoma of small intestine was poor, especially in cases where curative resection could not to be performed. Further study on the methods for early detection and effective systemic chemotherapy should be investigated.

Immunophenotyping and oncogene amplifications in tumors of the papilla of Vater

Carcinomas of the ampulla of Vater are rare and assumed to generally arise from preexisting adenomas (adenoma-carcinoma sequence). Histologically, distinct subtypes can be distinguished that were shown to differ significantly in terms of clinical outcome. Since pathologists usually receive bioptic tissue samples of ampullary tumors obtained during endoscopy, accurate classification of carcinoma subtypes can sometimes be difficult on morphological criteria alone. We therefore performed immunohistochemistry using a panel of established marker proteins (CK7, CK20, p21, p27, ESA, bax, and ephrin-B2) on 175 carcinoma, 111 adenoma, and 152 normal mucosa specimens of the ampulla of Vater and identified distinct immunoprofiles for every carcinoma subtype. Fluorescence in situ hybridization analyses of therapeutic target genes (c-myc, EGFR1, CCND1, HER2) found CCND1 to represent the most frequently amplified gene in our series (7.5%).

Hereditary colorectal cancer syndromes: familial adenomatous polyposis and lynch syndrome

Familial colorectal cancer (CRC) accounts for 10% to 20% of all cases of CRC. Two major autosomal dominant forms of heritable CRC are familial adenomatous polyposis (FAP) and Lynch syndrome (also known as hereditary nonpolyposis colorectal cancer). Along with the risk for CRC, both syndromes are associated with elevated risk for other tumors. Improved understanding of the genetic basis of these diseases has not only facilitated the identification and screening of at-risk individuals and the development of prophylactic or early-stage intervention strategies but also provided better insight into sporadic CRC. This article reviews the clinical and genetic characteristics of FAP and Lynch syndrome, recommended screening and surveillance practices, and appropriate surgical and nonsurgical interventions.

Immunohistochemical and molecular features of sporadic and FAP-associated duodenal adenomas of the ampullary and nonampullary mucosa

The pathogenesis of duodenal adenomas is not well elucidated. Much of the literature pertains to ampullary adenomas and those associated with familial adenomatous polyposis (FAP). In this study, we evaluated the molecular features of a series of sporadic duodenal adenomas (n=22) that developed distal to the ampulla, and compared them with the features of sporadic ampullary adenomas (n=9) and FAP-related polyps (n=12). Using a combination of immunohistochemical studies [cytokeratins 7 and 20, E-cadherin, beta-catenin, p53, MLH-1, MSH-2, MSH-6, and O6-methylguanine methyltransferase (MGMT)], DNA sequencing [beta-catenin, adenomatous polyposis coli (APC), p53, KRAS, and BRAF], and a polymerase chain reaction-based microsatellite instability assay; we assessed each case for abnormalities in the Wnt signaling and mitogen-activated protein kinase pathways and DNA repair mechanisms. Wnt signaling pathway abnormalities occurred in sporadic, nonampullary (82%), and ampullary (77%) adenomas at comparable rates, usually reflecting nuclear beta-catenin immunostaining (64% and 44%, respectively), and APC rather than beta-catenin, mutations. KRAS mutations were infrequent in sporadic, nonampullary adenomas (18%), and FAP-related adenomas (9%); moderately frequent in ampullary adenomas (44%); and none of the cases harbored BRAF mutations. Only 4 (13%) sporadic adenomas showed nuclear p53 staining, but no p53 mutations were detected in exons 5 to 8. Loss of O-methylguanine methyltransferase immunostaining was identified in 1 sporadic, nonampullary adenoma, and none of the polyps in any group showed loss of MLH-1, MSH-2, or MSH-6 staining, or high-frequency microsatellite instability. We conclude that sporadic and FAP-related adenomas show similar molecular features, regardless of their anatomic location. Similar to colorectal adenomas, they harbor APC and KRAS mutations; but BRAF mutations, p53 alterations, and DNA mismatch repair abnormalities are rare.

Prognostic factors in primary adenocarcinoma of the small intestine: 13-year single institution experience

Background

Adenocarcinoma of the small bowel is a relatively rare malignancy as compared to the other malignancies of the gastrointestinal tract. Nonspecific presentation and infrequent occurrence often leads to a delay in diagnosis and consequent poor prognosis. Various other factors are of prognostic importance while managing these tumors.

Methods

The medical records of a total of 27 patients treated for adenocarcinoma of the small bowel at Providence Hospital and Medical Centers from year 1990 through 2003 were reviewed retrospectively. Data were analyzed using SPSS software (version 10.0; SPSS, Inc., Chicago, IL). Survival analyses were calculated using the Kaplan Meier method with the log rank test to assess the statistical significance. The socio-demographics (age, gender) were calculated using frequency analyses.

Results

The patients included nine males and eighteen females with a median age at diagnosis of 62 years. Only 48% of the patients had an accurate preoperative diagnosis while another 33% had a diagnosis suspicious of small bowel malignancy. None of the patients presented in stage 1. The cumulative five-year survival was 30% while the median survival was 3.3 years. There was no 30-day mortality in the postoperative period in our series.

Conclusion

The univariate analysis demonstrated that tumor grade, stage at presentation, lymph nodal metastasis and resection margins were significant predictors of survival.

Two separated ileal adenocarcinomas in neurofibromatosis type 1

Patients with neurofibromatosis-1 (NF-1) have increased susceptibility to a variety of malignancies. Here, we document a rare case of two separated ileal adenocarcinomas in NF-1. The adenocarcinomas were surrounded by a diffuse tubular adenomatous lesion of the mucosa, and ganglion cells were scattered in the NF background. We found this case meaningful for several reasons: two separated adenocarcinomas arising in an unusual ileal segment, the association with precancerous tubular adenoma, and the presence of ganglion cells, which suggests ganglioneuromatosis in NF-1.

Expression of mucins, SIMA, villin, and CDX2 in small-intestinal adenocarcinoma

Expression of gastrointestinal biomarkers MUC1, MUC2, MUC5AC, small-intestinal mucin antigen (SIMA), villin, and CDX2 has been studied in colorectal adenocarcinoma (CRC). Little is known, however, about their expression in small-intestinal adenocarcinoma (SIA). We immunohistochemically compared 30 SIAs with 48 CRCs for the expression of these biomarkers. The results showed that all 6 proteins were variably expressed in SIA, but the frequencies of expression were significantly lower than those for CRC with the exception of MUC1. Specifically, positive staining for MUC1, MUC2, MUC5AC, SIMA, villin, and CDX2 was observed in 16 (53%), 17 (57%), 12 (40%), 15 (50%), 20 (67%), and 18 (60%) of SIAs and 25 (52%), 43 (90%), 39 (81%), 45 (94%), 47 (98%), and 47 (98%) of CRCs, respectively. In addition, SIAs more frequently exhibited a focal staining pattern for MUC2, MUC5AC, SIMA, and villin, whereas more diffuse immunoreactivity was evident in CRCs. Focal staining for MUC1 and diffuse staining for CDX2 were common for SIAs and CRCs. Furthermore, poorly differentiated SIAs tended to express MUC1 more frequently when compared with well- and moderately differentiated SIAs. These observations further support the notion that SIA is immunophenotypically distinct from CRC despite their morphologic similarity.

The APC E1317Q and I1307K polymorphisms in non-colorectal cancers

Mutation of the adenomatous polyposis coli (APC) gene is an important initiating factor in the early stages of the multi-step colorectal cancer (CRC) carcinogenesis. APC E1317Q and I1307K variants have been linked to CRC. The aim of this study was to examine the association of these variants with non-colorectal cancers. Mutation screening was performed using real-time PCR. The APC E1317Q variant was detected in 1.25% individuals undergoing testing. Among 2076 patients that were analyzed for this mutation, 404 had cancer outside of the colon. None of the non-colorectal cancer patients was a carrier of the E1317Q polymorphism. The I1307K variant was found in 32 subjects with non-CRC (7.9%). We conclude herein that the E1317Q gene variant in the APC gene is not found in cancers outside of the colon. The prevalence of the more common I1307K variant is similar to that of CRC.

Small bowel tumors

WCE is a noninvasive diagnostic technique that visualizes the entire small intestine and identifies lesions in parts of the small bowel not reached by traditional endoscopy. Although further studies are needed to define the exact role of WCE for diagnosing and managing small bowel tumors, its sensitivity has been shown to be superior to PE and small bowel follow-through in regard to diagnosing patients who have obscure GI bleeding, the most common indication for capsule endoscopy in the authors' series of patients with documented small bowel tumors. As more material is published, capsule endoscopy likely will be confirmed to be the diagnostic procedure of choice in patients with suspected small bowel tumors.

Associations between small intestine cancer and other primary cancers: an international population-based study

Cancer of the small intestine is a rare neoplasm, and its etiology remains poorly understood. Analysis of other primary cancers in individuals with small intestine cancer may help elucidate the causes of this neoplasm and the underlying mechanisms. We included 10,946 cases of first primary small intestine cancer from 13 cancer registries in a pooled analysis. The observed numbers of 44 types of second primary cancer were compared to the expected numbers derived from the age-, gender- and calendar period-specific cancer incidence rates in each registry. We also calculated the standardized incidence ratios (SIR) for small intestine cancer as a second primary after other cancers. There was a 68% overall increase in the risk of a new primary cancer after small intestine carcinoma (SIR = 1.68, 95% confidence interval [CI] = 1.47-1.71), that remained constant over time. The overall SIR was 1.18 (95% CI = 1.05-1.32) after carcinoid, 1.29 (1.01-1.63) after sarcoma, and 1.27 (0.78-1.94) after lymphoma. Significant (p < 0.05) increases were observed for cancers of the oropharynx, colon, rectum, ampulla of Vater, pancreas, corpus uteri, ovary, prostate, kidney, thyroid gland, skin and soft tissue sarcomas. Small intestine cancer as a second primary was increased significantly after all these cancers, except after oropharyngeal and kidney cancers. Although some of the excess may be attributable to overdiagnosis, it is plausible that most additional cases of second primary cancers were clinically relevant and were due to common genetic (e.g., defects in mismatch or other DNA repair pathways) and environmental (e.g., dietary) factors.

Initial experience of videocapsule endoscopy for diagnosing small-bowel tumors in patients with GI polyposis syndromes

BACKGROUND

Small-bowel tumors frequently occur in familial adenomatous polyposis and other GI polyposis syndromes. These tumors are difficult to detect with conventional techniques. Our aim was to assess the utility of videocapsule endoscopy in the detection of small-bowel tumors in this setting.

METHODS

We examined 19 familial adenomatous polyposis patients and 3 patients with either Peutz-Jeghers syndrome, hyperplastic polyposis, or Cowden disease.

OBSERVATIONS

Prevalence of small-bowel polyps on videocapsule endoscopy was 59% in all patients, 52.6% in familial adenomatous polyposis patients, and 75% in a subgroup of familial adenomatous polyposis patients with exon 15 mutations. Videocapsule endoscopy was safe and well tolerated in all patients.

CONCLUSIONS

Videocapsule endoscopy has a high yield in detecting small-bowel tumors in patients with GI polyposis syndromes. It may be especially indicated in familial adenomatous polyposis patients with the aggressive phenotype of the disease, e.g., mutations in exon 15.

Incidence of Small Bowel Cancer in the United States and Worldwide: Geographic, Temporal, and Racial Differences

OBJECTIVE

To examine the demographic and geographic patterns of small bowel cancer incidence in the United States and worldwide.

METHODS

Incidence data from the Surveillance, Epidemiology, and End Results (SEER) program between 1973 to 2000 were used to analyze the four histologic types of small bowel cancer, adenocarcinomas, carcinoid tumors, lymphomas, and sarcomas. International comparisons were made using data from Cancer Incidence in Five Continents (CIVIII). Geographic correlations between small bowel and both large bowel and stomach cancer incidence, were performed.

RESULTS

Men had higher rates than women for all types of small bowel cancer. Blacks had almost double the incidence of carcinomas and carcinoid tumors compared to whites (10.6 vs. 5.6 per million people; 9.2 vs. 5.4 per million people, respectively). Small bowel cancer incidence has risen, with the greatest increase for carcinoid tumors (21%) and black men (120%). A geographic correlation between small and large bowel cancer incidence, but not small bowel and stomach cancer, were observed.

CONCLUSIONS

Small bowel cancer incidence in the U.S. is higher in blacks compared to whites, particularly for carcinomas and carcinoid tumors. Small bowel cancer incidence is rising, particularly in black men. The geographic correlation between large and small bowel cancer suggests shared etiologies.

Small bowel adenocarcinoma in patients with Crohn's disease compared with small bowel adenocarcinoma de novo

BACKGROUND

Data concerning small bowel adenocarcinoma (SBA) in Crohn's disease (CD) come from case reports and small retrospective series. The aim of this study was to further describe SBA in patients with CD and compare it with SBA de novo.

METHODS

Twenty patients with CD with SBA recruited in French university hospitals were studied and compared with 40 patients with SBA de novo recruited from a population-based registry. SBA occurred after a median time of 15 years of CD and was located within the inflamed areas of the ileum (n=19) or jejunum (n=1), whereas in patients with SBA de novo, it was distributed all along the small intestine. Median age at diagnosis of SBA was 47 years (range, 33-72 yr) in patients with CD and 68 years (range, 41-95 yr) in those with SBA de novo.

RESULTS

The cumulative risk of SBA, assessed in a subgroup of patients, was 0.2% and 2.2% after 10 and 25 years of ileal CD, respectively. SBA accounted for 25% and 45% of the risk of gastrointestinal carcinoma after 10 and 25 years of CD, respectively. Diagnosis was made preoperatively in 1/20 patients with CD and 22/40 patients with SBA de novo. Signet ring cells were found in 35% of patients with CD but not in patients with SBA de novo. Relative survival was not significantly different in these 2 categories of patients (54 versus 37% and 35 versus 30% in patients with and without CD at 2 and 5 yr, respectively).

CONCLUSIONS

SBA in CD is different from SBA de novo. It arises from longstanding ileal inflammation and is difficult to diagnose. SBA cumulative risk increases after 10 years of CD and is likely to cause premature mortality in patients with early-onset CD.

'Metachronous' adenocarcinoma of the small intestine

Adenocarcinoma of the small intestine accounts for less than 1% of primary gastrointestinal malignancies (1). Small intestine contains 75% of the length of the gastrointestinal tract with 90% of the surface mucosal area, and yet carcinoma is rare. Symptoms of small bowel adenocarcinoma are vague and non-specific, and this region is relatively inaccessible which together contributes to their late diagnosis and poor prognosis. The authors report a case of two primary adenocarcinomas of the small intestine in the same patient.

Differential Expression of α-Methylacyl Coenzyme A Racemase in Adenocarcinomas of the Small and Large Intestines

Alpha-methylacyl coenzyme A racemase (AMACR), a novel immunomarker for prostatic adenocarcinoma, has recently been shown to be expressed in a number of malignancies including colorectal adenocarcinoma. In the current study, 59 surgically resected primary small intestinal adenocarcinomas (34 ampullary and 25 non-ampullary) were immunohistochemically examined for AMACR expression and compared with 66 colorectal adenocarcinomas (including 24 secondary tumors involving the small intestine by direct extension or metastasis). The results show that no AMACR immunoreactivity was detected in normal-appearing small and large intestinal mucosa. While 41 of 66 (62%) colorectal adenocarcinomas exhibited a variable degree of cytoplasmic staining, only 1 of 25 (4%) non-ampullary and 2 of 34 (6%) ampullary small intestinal adenocarcinomas showed positive AMACR immunoreactivity (P < 0.0001). Interestingly, AMACR appeared to be less frequently expressed in mucinous or poorly differentiated colorectal adenocarcinomas when compared with non-mucinous or better-differentiated counterparts, suggesting an association with microsatellite instability status. These results extend our previous observations that small intestinal adenocarcinomas differ markedly from colorectal adenocarcinomas despite their morphologic similarity. The different AMACR expression patterns may not only provide an additional diagnostic tool in the distinction between adenocarcinomas of the small and large intestinal origins but may also shed light on further understanding of intestinal tumorigenesis.

Pathogenesis and risk factors of small bowel adenocarcinoma: a colorectal cancer sibling?

Small bowel adenocarcinoma (SBA) is a very rare entity accounting for one-fourth of the small intestine neoplasms. Usually accompanied by nonspecific symptoms occurring late in the course of the disease, they are associated with a dismal prognosis. It appears that SBA shares several genetic characteristics with large bowel tumors, but also has unique features. The purpose of this article is to review pathogenesis and risks factors of SBA to better understand its molecular features as well as its resemblances and dissimilarities with colorectal cancer (CRC). Better understanding of sporadic and hereditary genetic pathways potentially involved will undoubtedly lead to better prevention and therapeutic management of this rare but aggressive disease.

Die Technik der pankreaserhaltenden Duodenektomie

Even in pancreatic surgery, as in other organs, there is a tendency towards subtle organ-preserving techniques. Benign duodenal tumors which cannot be resected transduodenally or multiple dysplastic duodenal adenomas in patients with familial adenomatous polyposis (FAP) usually require partial pancreaticoduodenectomy. However, pancreas-preserving duodenectomy may represent a viable alternative. This technique allows for the resection of the entire duodenum without resection of the pancreatic head. Large duodenal adenomas, multiple adenomas with dysplasia in patients with FAP, and based on the literature extended duodenal injury after trauma may represent indications for this surgical technique. Compared with duodenopancreatectomy, this intervention can be performed with a comparably low morbidity and leads to good functional results. Beside the preservation of pancreatic parenchyma and the reduction of the number of anastomoses, this technique offers the advantage of uncomplicated endoscopic follow-up. In this article we describe the surgical technique of pancreas-preserving duodenectomy and our experience with this intervention.