Adenocarcinoma of the small bowel: a 60-yr perspective derived from M. D. Anderson Cancer Center Tumor Registry

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Risk factors for small intestinal adenocarcinomas that are common in the proximal small intestine

The frequency of primary small intestinal adenocarcinoma is increasing but is still low. Its frequency is approximately 3% of that of colorectal adenocarcinoma. Considering that the small intestine occupies 90% of the surface area of the gastrointestinal tract, small intestinal adenocarcinoma is very rare. The main site of small intestinal adenocarcinoma is the proximal small intestine. Based on this characteristic, dietary animal proteins/lipids and bile concentrations are implicated and reported to be involved in carcinogenesis. Since most nutrients are absorbed in the proximal small intestine, the effect of absorbable intestinal content is a suitable explanation for why small intestinal adenocarcinoma is more common in the proximal small intestine. The proportion of aerobic bacteria is high in the proximal small intestine, but the absolute number of bacteria is low. In addition, the length and density of villi are greater in the proximal small intestine. However, the involvement of villi is considered to be low because the number of small intestinal adenocarcinomas is much smaller than that of colorectal adenocarcinomas. On the other hand, the reason for the low incidence of small intestinal adenocarcinoma in the distal small intestine may be that immune organs reside there. Genetic and disease factors increase the likelihood of small intestinal adenocarcinoma. In carcinogenesis experiments in which the positions of the small and large intestines were exchanged, tumors still occurred in the large intestinal mucosa more often. In other words, the influence of the intestinal contents is small, and there is a large difference in epithelial properties between the small intestine and the large intestine. In conclusion, small intestinal adenocarcinoma is rare compared to large intestinal adenocarcinoma due to the nature of the epithelium. It is reasonable to assume that diet is a trigger for small intestinal adenocarcinoma.

Chemotherapy for patients with unresectable or metastatic small bowel adenocarcinoma: a systematic review

BACKGROUND

There is no standard chemotherapy available for unresectable or metastatic small bowel adenocarcinoma (SBA) because of its rarity. This systematic review aims to assess the efficacy and safety of chemotherapy for patients with unresectable or metastatic SBA.

METHODS

In accordance with the PRISMA statements, literature search was conducted using PubMed, Scopus, and the Cochrane Central Register of Controlled Trials. The included studies were prospective randomized, nonrandomized, or observational studies. Risk of bias was assessed the ROBINS-I tool.

RESULTS

Seven prospective single-arm Phase II studies were included in this review. Six of them were assessed as having a moderate risk of bias and one as having a serious risk of bias. A meta-analysis was not performed, because the studies were single-arm. Systemic chemotherapy based on fluoropyrimidine regimens achieved favorable outcomes with acceptable adverse effects as a first therapy; however, the regimens differed in each study. The object response rate was 18-50%, and the disease control rate was 29-87%. With 5-fluorouracil, adriamycin, and mitomycin-C regimen, one treatment-related death occurred. A second line of therapy including chemotherapy with nab-paclitaxel also showed favorable efficacy. The object response rate was 20%, and the disease control rate was 50%.

CONCLUSIONS

Systemic chemotherapy based on fluoropyrimidine regimens was mainly used for unresectable or metastatic SBA. While it may achieve favorable outcomes with acceptable adverse effects, further evidence is needed.

Spectral CT Imaging in the Differential Diagnosis of Small Bowel Adenocarcinoma From Primary Small Intestinal Lymphoma

PURPOSE

To investigate the value of dual-energy spectral computed tomography (CT) imaging in the differential diagnosis of small bowel adenocarcinoma (SBA) from primary small intestinal lymphoma (PSIL).

MATERIALS AND METHODS

We retrospectively analyzed the images of 27 SBA cases and 15 PSIL cases. These patients underwent spectral CT imaging in the arterial phase (AP) and venous phase (VP). CT attenuation values of tumors at different energy levels were measured to generate spectral attenuation curve and to calculate curve slope (λ_HU). Iodine concentration (IC) in tumors at AP and VP were measured and normalized to that of aorta as normalized iodine concentration (NIC). Independent samples t test was used to analyze the spectral CT parameters; Receiver operating characteristic curves were generated to evaluate the diagnostic efficacy of each parameter.

RESULTS

There were significant differences between SBA and PSIL in IC (2.09 ± 0.71 vs 1.33 ± 0.15 mg/ml), NIC (0.20 ± 0.06 vs 0.13 ± 0.02) and slope (λ_HU) (2.78 ± 1.06 vs 1.86 ± 0.30) in AP and (1.86 ± 0.68 vs 1.37 ± 0.18 mg/ml for IC; 0.47 ± 0.13 vs 0.33 ± 0.02 for NIC and 2.00 ± 0.56 vs 1.50 ± 0.26 for λ_HU) in VP (all p < 0.05). For the CT value measurement, there were significant differences between SBA and PSIL in the 40-60keV energy range (p < 0.05), but not in the 70-140keV range (p > 0.05). Using 1.38 mg/ml as a threshold value for iodine concentration at AP, one could obtain the area-under-curve of 0.93 for receiver operating characteristic study and sensitivity of 94% and specificity of 85% for differentiating SBA from PSIL. The sensitivity and specificity values were significantly higher than the respective values of 62% and 60% with the conventional CT numbers at 70keV.

CONCLUSION

Quantitative parameters obtained in spectral CT, especially iodine concentration in AP, provide high accuracy for differentiating SBA from PSIL.

Molecular Diagnostics in the Neoplasms of Small Intestine and Appendix: 2018 Update

Neoplasms of the small intestine are rare in comparison with colorectal tumors. The most common tumor types arising in the small intestine are adenocarcinomas, well-differentiated neuroendocrine tumors, gastrointestinal stromal tumors, and lymphoma. Primary appendiceal neoplasms are rare and found in less than 2% of appendectomy specimens with an incidence of approximately 1.2 cases per 100,000 people per year in the United States. This article explores molecular diagnostics in the neoplasms of small intestine and appendix.

Treatment results of small bowel perforations due to unusual causes

Objectives:

Although non-traumatic Small Bowel Perforations (SBPs) are rare, they have high rates of morbidity and mortality in case of late presentation. Aetiological factors vary across different geographical regions. In this paper, SBPs caused by anything other than trauma and other well-known causes are presented and the current literature is reviewed.

Methods:

The study was conducted at General Surgery Clinics of two different tertiary university hospitals between January 2008 and September 2016. The authors directly involved in managing the patients. This study was approved by the ethical institutional board and was performed at the Department of General Surgery, School of Medicine, Sakarya University. The medical records of patients retained in both hospitals are electronic. Medical records of subjects who had undergone emergency operations with a prediagnosis of acute abdomen in single center, and were determined to have SBPs due to unusual causes, were investigated retrospectively. Patients with aetiological factors such as trauma, mesenteric vascular disease, internal and external hernias, intra abdominal adhesions, inflammatory bowel diseases, and iatrogenic causes were excluded.

Results:

In total, 35 patients were evaluated, 20 (57.1%) males and 15 (42.9%) females. The mean age of the cases was 51.6 (18–88) years. Mean time until admission at the hospital was 1.4 days (range 0.25–7 days). The most frequent aetiological factors were various malignancies (10 cases, 28.5%) and perforation of Meckel’s diverticulum (8 cases, 22.8%). It was surprising to detect a considerable rate of perforation due to bezoars (6 patients, 17.1%).

Conclusions:

Post-operative consequences of SBPs due to unusual causes are similar with those related to common, known causes. Factors affecting the clinical course are presentation time and patients’ clinical status in admission, not aetiology.

Adenocarcinoma of jejunum

Although gastrointestinal malignancy is still the major concern of health problems in Worldwide and Thailand, but small intestinal malignancy is extremely rare. The location of small intestinal malignancy is duodenum (73.6%), jejunum (13.2%) and ileum (13.2%). The diagnosing of small intestinal malignancy usually delays due to inaccessible of esophagogastroduodenoscopy especially jejunum and ileum causing poor prognostic outcomes. We reported our case of jejunal adenocarcinoma.

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.

Role of computed tomography angiography in detection and staging of small bowel carcinoid tumors

Small-bowel carcinoid tumors are the most common form (42%) of gastrointestinal carcinoids, which by themselves comprise 70% of neuroendocrine tumors. Although primary small bowel neoplasms are overall rare (3%-6% of all gastrointestinal neoplasms), carcinoids still represent the second most common (20%-30%) primary small-bowel malignancy after small bowel adenocarcinoma. Their imaging evaluation is often challenging. State-of-the-art high-resolution multiphasic computed tomography together with advanced postprocessing methods provides an excellent tool for their depiction. The manifold interactive parameter choices however require knowledge of when to use which technique. Here, we discuss the imaging appearance and evaluation of duodenal, jejunal and ileal carcinoid tumors, including the imaging features of the primary tumor, locoregional mesenteric nodal metastases, and distant metastatic disease. A protocol for optimal lesion detection is presented, including the use of computed tomography enterography, volume acquisition, computed tomography angiography and three-dimensional mapping. Imaging findings are illustrated with a series of challenging cases which illustrate the spectrum of possible disease in the small bowel and mesentery, the range of possible appearances in the bowel itself on multiphase data and extraluminal findings such as the desmoplastic reaction in mesentery and hypervascular liver metastases. Typical imaging pitfalls and pearls are illustrated.

Lifestyle factors and small intestine adenocarcinoma risk: A systematic review and meta-analysis

BACKGROUND

Although the incidence of small intestinal adenocarcinoma (SIA) is low, rates are increasing and little information regarding modifiable lifestyle risk factors is available.

AIM

To provide a systematic review of lifestyle factors and SIA risk.

METHODS

Ovid MEDLINE, EMBASE and Web of science were searched from inception to week 1 October 2013. Nine publications that reported on SIA risk in relation to alcohol intake (n=6), tobacco smoking (n=6), diet (n=5), body mass (n=3), physical activity (n=1), hormone use (n=1) and/or socio-economic status (n=3) were retrieved. Results for alcohol, smoking and SIA risk were pooled using random-effects meta-analyses to produce relative risks (RR) and 95% confidence intervals (CI).

RESULTS

The summary RR for individuals consuming the highest versus lowest category of alcohol intake was 1.51 (95% CI 0.83-2.75; n=5 studies) with significant increased risks emerging in sensitivity analysis with reduced heterogeneity (RR: 1.82, 95% CI: 1.05-3.15; n=4 studies). The pooled SIA RR for individuals in the highest versus lowest category of smoking was 1.24 (95% CI 0.71-2.17; n=5 studies). In relation to dietary factors, high fibre intakes and normal body weight may be protective, while high intakes of red/processed meat and sugary drinks may increase SIA risk. Evidence on socio-economic status and SIA risk was equivocal. Data on other factors were too sparse to draw any conclusions.

CONCLUSIONS

Alcohol may be associated with an increased risk of SIA. Further investigation of lifestyle factors, particularly alcohol, smoking and diet, in the aetiology of this cancer is warranted in large consortial studies.

Adenocarcinoma with adenoma in the jejunum suggesting an adenoma-carcinoma sequence in the small bowel: A case report

Other than that in the duodenum, adenocarcinoma in the small bowel is rare. The present study describes a case of adenocarcinoma with adenoma in the jejunum. A 70-year-old male was admitted to hospital due to dehydration induced by abdominal discomfort and difficulty with oral intake. Computed tomography revealed a tumor in the upper side of the jejunum, which was subsequently resected. The tumor contained adenocarcinoma and adenoma. The protein expression of p53 and Ki-67 was analyzed in the normal mucosa, adenoma and adenocarcinoma. The number of epithelial cells expressing p53 and Ki-67 was found to increase in the adenoma tissue compared with that in the normal mucosa. In the adenocarcinoma tissue, the number of cells expressing p53 and Ki-67 further increased, suggesting that an adenoma-adenocarcinoma sequence may occur in the small bowel, similar to that observed in the large bowel.

The clinical pathological features, diagnosis, treatment and prognosis of small intestine primary malignant tumors

The aim of the study was to describe and analyze the clinicopathological features and diagnosis of Chinese patients with small intestine primary malignant tumors and to explore the best therapy to small bowel adenocarcinoma (SBA). More than 26,000 patients with digestive tract malignant tumors received treatment in PLA hospital from 2000 to 2011, and among them, there were 887 patients who had small intestine primary malignant tumors, and 666 of 887 patients had the completed basic clinical documents. We retrospectively analyzed the correlation between clinical and pathological features of the 666 patients and analyzed the survival and prognosis of 173 SBA patients with follow-up data. Both the number of patients with primary malignant tumors of the small intestine and the number of patients who received chemotherapy showed an increasing trend. The ratio of male to female was 1.58:1. The male patients significantly exceed the female patients with tumors of non-ampullary duodenum, jejunum and duodenal ampulla; and most of the patients are over 60 years of age. For patients burdened with either of the pathological types of tumors, the males exceeded the females, but there was no significant difference. Abdominal pain was the main clinical manifestation for patients with tumors of non-ampullary duodenum, jejunum and ileum, and the most common clinical manifestations were jaundice and abdominal pain for patients with ampullary duodenal tumors, adenocarcinoma, neuroendocrine tumors and sarcoma. In addition, patients with stromal tumors were prone to gastrointestinal bleeding. Gastrointestinal endoscopy was the most common examinational procedure. Patients under 60 years of age were prone to surgery and chemotherapy after surgery, and patients over 60 years of age were prone to supportive treatment and chemotherapy without surgery. The medium overall survival of patients who received surgery without chemotherapy, chemotherapy after surgery, chemotherapy without surgery and supportive treatment were 40.0, 35.0, 9.0 and 7.5 months, respectively. For the 173 SBA patients with follow-up data, treatment, age and distant metastasis were important prognostic factors; 149 of 173 SBA patients received only surgery, and the depth of tumor invasion, lymph node metastasis and surgical approach were important prognostic factors. Adjuvant chemotherapy had not provided significant benefit to prolong OS in patients with adenocarcinoma. The incidence of small intestine primary malignant tumors is very low, and it is difficult to diagnose. The patients should be aggressively treated and regularly followed up with related clinical and pathological features. Currently, surgery is the most effective treatment, and the role of chemotherapy needs further large-scale clinical studies.

Racial and ethnic variation in the incidence of small-bowel cancer subtypes in the United States, 1995-2008

BACKGROUND

Small-bowel cancer is uncommon and, accordingly, little is known about the epidemiology of this malignancy, especially by race and subtype.

OBJECTIVE

The objective of this analysis was to describe the distribution of small-bowel cancer in the United States by demographic, pathological, and clinical features.

DESIGN

This study was retrospective in design.

SETTING

Data from 26 population-based cancer registries in the United States from 1995 to 2008 were used.

PATIENTS

Patients diagnosed with small-bowel cancer (topography codes C17.0-17.3 and C17.8-17.9) were included.

MAIN OUTCOME MEASURES

The primary outcomes measured were race- and histology-specific incidence (age-adjusted rate trends and age-specific rates) of small-bowel cancer.

RESULTS

A total of 56,223 men and women diagnosed with small-bowel cancer were identified. The overall age-adjusted incidence rates for small-bowel cancer were 26.1 in men and 17.7 in women. Neuroendocrine tumors were the most common histological types of small-bowel cancer in men and women, followed by carcinoma, lymphoma, and sarcoma. In comparison with whites, the rate of small-bowel cancer was 42% greater in black men, 46% greater in black women, 34% lower in Asian-Pacific Islander men, and 37% lower in Asian-Pacific Islander women. Rates of small-bowel cancer were 24% lower in Hispanic men and 15% lower in Hispanic women than rates in non-Hispanics. The excess of small-bowel cancer in blacks and the deficit in Asian-Pacific Islanders were attributable mainly to the incidence of adenocarcinoma and carcinoid tumors. The incidence of GI stromal tumor was significantly higher among Asian-Pacific Islanders.

CONCLUSIONS

This is one of the largest studies of small-bowel cancer to date. These cancer registry data showed substantial racial and ethnic variation in the incidence of histological subtypes of small-bowel malignancy that suggest possible etiologic diversity and/or disparities in detection.

Recurrence of primary squamous cell carcinoma of the ileum diagnosed by elevation of serum SCC: report of a case

Primary squamous cell carcinoma of the intestine is extremely rare. This report describes a patient with primary squamous cell carcinoma of the small intestine. A 72-year-old Japanese woman was referred to our hospital because of a diagnosis of intestinal obstruction. She underwent laparotomy owing to the diagnosis of mechanical intestinal obstruction due to a pelvic mass after conservative treatment. The affected ileum was resected, and histopathological examination revealed proliferation of differentiated squamous cell carcinoma at the submucosal area with no adenocarcinoma component. At the 4th month after the operation, the level of serum squamous cell carcinoma (SCC) antigen was elevated. At 6 months after the operation, the serum SCC value was further elevated, and enhanced CT revealed two new pelvic tumors with enhancement at the mesentery and free space. A second laparotomy was performed 8 months after the operation. Histopathological examination showed differentiated squamous cell carcinoma as in the first operation. The level of serum SCC decreased at the 28th postoperative day. Chemotherapy including carboplatin and paclitaxel was performed as an adjuvant regimen. The patient has experienced no recurrence of squamous cell carcinoma for 55 months.

Crohn's disease and small bowel adenocarcinoma: a population-based case-control study

BACKGROUND

Although Crohn's disease (CD) is thought to predispose to adenocarcinomas of the small bowel, the association has not been well studied in an older population.

AIMS

The objective of our study was to evaluate the association of CD with small bowel cancer in a population-based case-control study.

METHODS

All cases of small bowel cancer in persons 67 and older in the Surveillance, Epidemiology and End Results catchment area and in the Medicare claims data base were compared with cancer-free controls residing in the same geographic area. We used multivariable logistic regression models adjusted for demographic and other factors.

RESULTS

We identified 923 cases of small bowel cancer and 142,273 controls. Although we found a strong association between CD and small bowel cancer (OR = 12.07; 95% CI: 6.07-20.80; P < 0.001), the prevalence of CD in patients with small bowel cancer was low (1.6%).

CONCLUSIONS

Although CD is a significant risk factor for small bowel cancers among individuals older than 67, the absolute risk is small.

IMPACT

Older individuals with CD can be reassured that although there is an association between CD and small bowel cancer, the absolute risk remains small.

Imaging of malignant neoplasms of the mesenteric small bowel: new trends and perspectives

This article describes the recent advances in radiological imaging of malignant neoplasms of the mesenteric small bowel and provides an outline of new trends and perspectives that can be anticipated. The introduction of multidetector row technology, which allows the acquisition of submillimeter and isotropic voxels, has dramatically improved the capabilities of computed tomography in the investigation of the mesenteric small bowel. This technology combined with optimal filling of small bowel loops through the use of appropriate enteral contrast agents has markedly changed small bowel imaging. Computed tomography-enteroclysis, which is based on direct infusion of enteral contrast agent into the mesenteric small bowel through a naso-jejunal tube, provides optimal luminal distension. By contrast, computed tomography-enterography is based on oral administration of enteral contrast agent. These two techniques are now well-established ones for the detection and the characterization of small bowel neoplasms. During the same time, combining the advantages of unsurpassed soft tissue contrast and lack of ionizing radiation, magnetic resonance imaging has gained wide acceptance for the evaluation of patients with suspected small bowel neoplasms. Rapid magnetic resonance imaging sequences used in combination with specific enteral contrast agents generate superb images of the mesenteric small bowel so that magnetic resonance-enteroclysis and magnetic resonance-enterography are now considered as effective diagnostic tools for both the detection and the characterization of neoplasms of the mesenteric small bowel. Recent improvements in image post-processing capabilities help obtain realistic three-dimensional representations of tumors and virtual enteroscopic views of the small bowel that are useful for the surgeon and the gastroenteroenteologist to plan surgical or endoscopic interventions. Along with a better knowledge of the potential and limitations of wireless capsule endoscopy and new endoscopic techniques, these recent developments in radiological imaging reasonably suggest that substantial changes in the investigation of small bowel tumors may be anticipated in a near future, thus potentially create a new paradigm shift after standard small bowel follow-through study has been universally abandoned.

Intramucosal adenocarcinoma of the ileum originated 40 years after ileosigmoidostomy

Background

Small bowel adenocarcinomas (SBAs) are rare carcinomas. They are asymptomatic and usually neither endoscopy nor contrast studies are performed for screening

Case presentation

A 72-year-old Japanese male had a positive fecal occult blood test at a regular check-up in 2006. He suffered appendicitis and received an ileosigmoidostomy in 1966. A colonoscopy revealed an irregular mucosal lesion with an unclear margin at the ileum side of the anastomosis. A mucosal biopsy specimen showed adenocarcinoma histopathologically. Excision of the anastomosis was performed for this patient. The resected specimen showed a flat mucosal lesion with a slight depression at the ileum adjacent to the anastomosis. Histological examination revealed a well differentiated intramucosal adenocarcinoma (adenocarcinoma in situ). Immunohistological staining demonstrated the overexpression of p53 protein in the adenocarcinoma.

Conclusion

Adenocarcinoma of the ileum at such an early stage is a very rare event. In this case, there is a possibility that the ileosigmoidostomy resulted in a back flow of colonic stool to the ileum that caused the carcinogenesis of the small intestine.

Small bowel adenocarcinoma

Small bowel cancers are rare, accounting for only about 6000 cases/year in the United States, approximately 25% of which are small bowel adenocarcinomas. Small bowel adenocarcinomas have traditionally been considered to be highly fatal due to their nonspecific presentation at the time of diagnosis, and to the lack of responsiveness to older chemotherapy regimens. However, that paradigm may be changing. Newer diagnostic techniques such as video capsule and double balloon enteroscopy may facilitate earlier diagnosis. In addition, modern chemotherapy regimens have produced improved response rates and survival rates, when compared to historical controls. Still, there remains great need for multi-institutional, cooperative group studies to define the optimal treatment of small bowel adenocarcinoma, both in the adjuvant and advanced/metastatic setting.

Usefulness of double-balloon endoscopy in the diagnosis of malignant small-bowel tumors

BACKGROUND & AIMS

Double-balloon endoscopy (DBE) enables endoscopic and histopathologic diagnosis of malignant small-bowel tumors (MSBT). This study examined the clinical features of patients with MSBT and evaluated the usefulness of DBE in the diagnosis of MSBT.

METHODS

We retrospectively examined consecutive DBE studies of 358 patients who underwent DBE in our hospital between December 2003 and October 2007 because of suspected or established small-bowel disease.

RESULTS

Fourteen patients with MSBT were diagnosed by DBE. The most common type was primary adenocarcinoma (8 patients), followed by metastatic carcinoma (3 patients) and malignant lymphoma (3 patients). Half of these patients presented with obscure gastrointestinal bleeding (OGIB). Histopathologic diagnosis was obtained in 11 of 14 patients.

CONCLUSIONS

Of 180 patients with OGIB, MSBT accounted for only 3.9%, however, 50% of patients with MSBT presented with OGIB. OGIB is an important clinical feature of small-bowel malignancy, which can be diagnosed by DBE.

Diagnosis and staging of small bowel tumours

Small bowel neoplasms comprise only 1% of gastrointestinal neoplasms. Despite their rarity, it is important to diagnose small bowel tumours early to maximize patient survival.