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Neuroendocrine tumors of the pancreas are uncommon neoplasms. They may occur as a sporadic lesion or as part of a genetic disease such as the multiple endocrine neoplasia type 1 (MEN-1) syndrome. Sporadic tumors usually arise as a single lesion, whereas those associated with familial disorders generally are multifocal. Tumors may be classified as functioning or nonfunctioning depending on whether or not there is excess hormone production correlated with a clinical syndrome. Clinical suspicion is based on development of the constellation of clinical symptoms characteristic of excess hormone production. In the case of a nonfunctioning tumor, its presence often becomes apparent because of symptoms from local tumor growth or metastatic disease. Once biochemical studies confirm the diagnosis and cross-sectional imaging exclude metastatic disease, endoscopic ultrasound (EUS) can localize the tumor and guide surgical management, providing potentially curative resection. [ABSTRACT FROM AUTHOR]

Pancreatic cancer is the fourth most common cause of cancer-related mortality in the United States (1). The 5-yr survival rate is the lowest among all cancers, with estimates ranging from 0.4 to 4%. The only potentially curative treatment for pancreatic cancer is surgical resection. However, because the disease is generally advanced at presentation, only 10-20% of patients are eligible for attempted curative resection. In these patients who undergo pancreaticoduodenectomy, 5-yr survival is somewhat better, about 20% (2). The epidemiology and clinical features of pancreatic cancer will be reviewed. A careful examination of current imaging technology in the staging, diagnosis, and evaluation of pancreatic adenocarcinoma will also be discussed. [ABSTRACT FROM AUTHOR]

The focus of this chapter is to examine the role of endoscopic ultrasound (EUS) in the management of mediastinal lesions. EUS, owing to its diagnostic accuracy, tissue sampling capability, low morbidity, and time and cost savings has become an integral part of the multidisciplinary approach to the imaging and management of thoracic diseases. It is the intent of this chapter to outline the benefit of EUS as an adjunct to modalities such as bronchoscopy, positron emission tomography (PET), and computed tomography (CT) imaging in the evaluation of mediastinal diseases. [ABSTRACT FROM AUTHOR]

Pancreatic adenocarcinoma is one of the most lethal malignancies, with an overall 5-yr disease-free survival rate of 1-2% for all patients. Most patients with pancreatic cancer are not diagnosed until they have developed locally advanced or regionally disseminated disease that is not amenable to attempted curative surgical resection. Chemotherapy and radiation therapy have only modest benefit in this stage of the disease and typical survival is 6 mo. Among those patients with apparently resectable disease who undergo surgical exploration, between 20 and 40% are found to be unresectable, dependent on the pre-operative evaluation. Even those pancreatic cancer patients who have a margin-negative resection have a 5-yr disease-free survival of less than 30%, and approximately half of patients surviving 5 yr will relapse between 6 and 10 yr. Thus, the treatment of pancreatic cancer remains a significant challenge to the surgical, radiation, and medical oncologist. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) are noninvasive imaging techniques that can detect, characterize, and stage neoplasms of the biliary system and pancreas. In patients with suspected pancreatic cancer, MRI/MRCP can help distinguish those patients who are unresectable from those who are potentially resectable. In patients with pancreatic cysts, MRI assists in the distinction among pseudocysts, benign cystic lesions, and cystic pancreatic malignancies. Limitations of current MRI techniques include the inability to detect subcentimeter peritoneal metastases and the lack of sensitivity for identifying microscopic metastases within normal-sized lymph nodes. [ABSTRACT FROM AUTHOR]

The optimal approach has yet to emerge for the management of sporadic periampullary adenomas and upper gastrointestinal (GI) neoplasia complicating familial adenomatous polyposis (FAP). There are no randomized trials comparing different surgical and/or endoscopic modalities. Such studies may not be feasible given the infrequency of these conditions and the long follow-up period required for such a study. In the meantime, selection of the optimal approach for an individual patient will rely on a careful evaluation of the disease severity and extent in that patient and the utilization of the best available endoscopic and surgical expertise. [ABSTRACT FROM AUTHOR]

Cholangiocarcinoma is rare with an increasing incidence with age. There are a variety of diagnostic studies available to evaluate the presence and extent of cholangiocarcinoma. Unfortunately, the majority of symptomatic patients present with advanced disease and are not candidates for curative resection. Palliation in the majority of cases consists of endoscopic decompression of the biliary tract to decrease the morbidity of jaundice, which includes pruritus, impaired hepatic and renal function, and associated coagulopathy. More recently, complementary palliative modalities such as photo-dynamic therapy (PDT) and brachytherapy have emerged. [ABSTRACT FROM AUTHOR]

In 2004, the American Cancer Society estimated that approx 150,000 new cases of colorectal cancer would occur in the United States and that more than 57,000 Americans would die of the disease, making it the second most common cause of cancer-related death (1). Despite improvements in screening techniques, 30-40% of patients with colorectal cancer present with locoregionally advanced or metastatic disease and are not candidates for potentially curative therapy. Overall, progress in the surgical and neoadjuvant/adjuvant management of locally confined colorectal cancer has been rapid and very encouraging over the past several years. In addition, median survival in advanced disease has improved almost fourfold, as several new and active salvage systemic agents have emerged and been rapidly integrated into first-line regimens. [ABSTRACT FROM AUTHOR]

Endoscopic approaches have revolutionized the palliation of advanced pancreatic cancer. The ideal management consists of a team approach involving surgeons, endoscopists, radiologists, and oncologists. Further technical improvements are needed to tackle the problem of stent occlusion. Concurrent advances in the fields of interventional radiology and laparoscopic surgical oncology need to be readdressed and directly compared with endoscopic approaches in novel randomized controlled trials. [ABSTRACT FROM AUTHOR]

This chapter focuses on radiological imaging of colonic neoplasia. Examination of the colon is most often performed with barium radiography and computed tomography (CT). Ultrasonography, positron emission tomography, and magnetic resonance imaging (MRI) have minor roles in colon imaging. [ABSTRACT FROM AUTHOR]

Cystic neoplasms of the pancreas are an important entity for gastroenterologists and endoscopists because these lesions represent the best example of an early malignancy of the pancreas. In the past, cystic neoplasms of the pancreas were thought to be relatively rare, composing less than 10% of cancers of the pancreas. With the increasing use of cross-sectional imaging, an increasing number of these neoplasms are being seen. Cystic lesions of the pancreas are made up of a broad range of neoplastic cysts and inflammatory pseudocysts. The neoplastic cysts manifest a wide range of malignancy, from overtly malignant to premalignant lesions, and benign cystadenomas. Cystic neoplasms of the pancreas can be divided into two major categories, mucinous and nonmucinous lesions (Table 1) (1). There are three types of mucinous lesions, benign mucinous cystadenomas, malignant mucinous cystic lesions, and intraductal papillary mucinous neoplasms (IPMNs). The nonmucinous lesions include microcystic serous cystadenomas and the cystic endocrine tumors. [ABSTRACT FROM AUTHOR]

Colon cancer is a common but often preventable disease. Although surgery is the mainstay of therapy, endoscopic therapy is helpful in managing selected cases of early colorectal cancer (CRC) and may offer palliation in advanced CRC. The role of endoscopic mucosal resection (EMR), snare polypectomy, colonic stenting, argon plasma coagulation (APC), and photo-dynamic therapy (PDT) in colon cancer is discussed. [ABSTRACT FROM AUTHOR]

Rectal endoscopic ultrasound (RUS) has proven very beneficial in the staging of malignant neoplasm in the anus and rectum (1,2). Typically, imaging is performed using an adult standard radial ultrasound endoscope, commonly used in evaluation of the upper gastrointestinal tract (3). Based on RUS, the normal rectal wall architecture consists of a mucosal layer (muscularis mucosa and lamina propria—also referred to as superficial and deep layers), submucosa, muscularis propria, and surrounding perirectal fat tissue without a serosa/adventiaa layer (2). Carcinoma appears as a hypoechoic mass lesion with partial or total destruction of the normal wall layer. RUS has also been useful in examining for tumor invasion in the surrounding regional organs: which in males would include evaluating the bladder, seminal vesicles, prostate, and internal anal sphincters (IASs)/external anal sphincters (EASs); and in females would include evaluation of the bladder, uterus/vagina, and IASs/EASs (2,2). Moreover, RUS is very helpful in evaluation of malignant lymphadenopathy. All of these features are useful in the pre-operative staging of rectal and anal carcinomas (1,2). [ABSTRACT FROM AUTHOR]

Unlike screening, which is defined as the identification of unrecognized or asymptomatic disease in an average-risk population, endoscopic surveillance for colorectal cancer (CRC) is based on the premise that repeated evaluation of a high-risk population will identify patients either with cancer at an earlier, treatable stage, or those who are likely to develop cancer. The purpose of this chapter is to present the recommendations for endoscopic surveillance after colonoscopic polypectomy, CRC resection, and in the setting of inflammatory bowel disease, and to discuss the evidence on which these recommendations are based. Surveillance of these conditions in the setting of an inherited or familial CRC syndrome are not discussed here, but are reviewed in Chapter 18. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the second leading cause of cancer death in the United States. Each year approx 130,000 Americans are diagnosed with the disease and 50,000 will die of it (1). The cumulative lifetime risks of CRC and mortality from CRC are approx 3-6% and 2%, respectively. The majority of CRCs occur in individuals over 60 yr old, whom have no previous personal or family history of the disease. The major risk factors for these sporadic cases are advancing age and environmental exposures, most importantly diet. Approximately 20-25% of CRCs are in younger individuals or in those with a personal or family history of cancer, suggesting a heritable susceptibility (2). [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) remains the second leading cause of cancer death in the United States (1). It is estimated that approx 148,610 will be diagnosed with CRC and 55,170 will die from it in 2006 (1). However, mortality from CRC has been declining over the past 20 yr, felt largely to be due to earlier detection. The average lifetime risk is 6%, with men and women almost equally affected. Most cases are sporadic, apparently resulting from a combination of environmental and genetic factors (Fig. 1), although there are many known risk factors (Table 1). Screening for CRC has been advocated on the grounds that CRC is a major public health problem, it is preventable through removal of precursor lesions, it is curable if detected early (Fig. 2), and screening tests have been proven to impact disease outcomes. In fact, some screening strategies have been proven to reduce cancer mortality and many strategies are cost-effective (2,3). Unfortunately, CRC screening is under-utilized because of a variety of barriers to screening. [ABSTRACT FROM AUTHOR]

Gastric cancer remains among the 10 most common cancers in the world with variations in incidence and survival based on geographic sites. Gastric cancer is the second most common tumor worldwide with 60% of cases in developing countries (1). It appears that, worldwide, gastric cancer is second only to lung cancer with a reported 798,300 new cases in 1990 and is more common than, breast and colorectal cancer outside of the United States. The highest incidences are in Japanese men; rates are also increased in eastern Europe, South America, and eastern Asia, but lower in the United States, North Africa, and Australia (1). In contrast, esophageal cancer is relatively rare, being the seventh leading cause of death in men in the United States (2). Survival is poor, being only 37% for stage II, 11-18% for stage III, and 5% for stage IV. The effectiveness of surgery, chemotherapy, radiation therapy or the combination of the above modalities has been investigated for decades with varied results. [ABSTRACT FROM AUTHOR]

Carcinoid tumors are of neuroendocrine origin, and can produce bioactive peptides or amines that rarely produce clinical symptoms. These tumors are slow growing, and infrequently produce the so-called carcinoid syndrome, cardinal features of which are flushing and diarrhea. About two-thirds of carcinoid tumors are found in the gastrointestinal (GI) tract, one-fourth in the bronchopulmonary tree, and the remainder in the urogenital tract. Presentation, behavior, and malignant potential of carcinoid tumors are determined by the site at which they originate. Resection of the tumor is the only curative option, but advances in the understanding of the biology of carcinoids have produced therapies that can effectively treat symptoms caused by these tumors. [ABSTRACT FROM AUTHOR]

Primary gastrointestinal (GI) tract lymphomas account for 1-4% of gastric, small intestinal, and colonic malignancies. They arise from mucosa-associated lymphoid tissue (MALT) and most are B-cell non-Hodgkin's lymphomas. T-cell lymphomas of the bowel are usually associated with celiac disease. The GI tract is the most common site for extranodal non-Hodgkin's lymphomas with the stomach accounting for more than 75%. Accurate staging helps with prognosis and management. [ABSTRACT FROM AUTHOR]

Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors characterized by a spindle morphology and expression of the c-kit proto-oncogene. They occur primarily in the stomach and small intestine presenting with abdominal pain or bleeding, but may be found incidentally. These tumors may behave malignantly by metastasizing, invading adjacent organs, or recurring after resection. Tumor size more than 5 cm or more than 5 mitoses per high-power field (HPF) are most useful inpredicting subsequent malignant behavior. Endoscopy generally reveals a submucosal tumor that may have a central umbilication or ulcer. Endoscopic forceps biopsies are usually nondiagnostic. Endoscopic ultrasound (EUS) reveals a hypoechoic mass generally arising from the fourth endosonographic layer (muscularis propria). EUS-guided fine-needle aspiration (FNA) with staining of the specimen for the c-kit protein (CD-117) and CD-34 can establish the diagnosis. The treatment of choice is complete surgical resection for all tumors that have malignant features. Controversy surrounds whether small benign-appearing GISTs require resection. Patients with unresectable, metastatic and/or recurrent GISTs may be treated with the tyrosine kinase inhibitor imatinib mesylate with 80% of patients either responding or having stable disease. [ABSTRACT FROM AUTHOR]

Endoscopy may be used in the treatment of gastric cancer. Malignant lesions may be removed by mucosal resection or destroyed with the application of thermal energy or photo-dynamic therapy. Patients with obstructive symptoms may be palliated by thermal coagulation, placement of a stent, or creation of a venting gastrostomy. Those with bleeding might be treated with thermal coagulation or injection therapy although rebleeding is common. In patients with early gastric cancer (EGC), endoscopic mucosal resection (EMR) might be curative. Complications of endoscopic resection (ER) include pain, bleeding, and perforation. [ABSTRACT FROM AUTHOR]

Although the incidence of gastric cancer is declining, it remains a leading cause of cancer-related death worldwide. Prognosis in gastric cancer is highly correlated with tumor stage. Surgical therapy remains the definitive therapy. Accurate pre-operative staging is essential, especially in patients who may be marginal surgical candidates. Accurate staging also is of particular importance in early gastric cancer in which select lesions confined to the mucosa may be treated with local endoscopic mucosal resection. Endoscopic ultrasound (EUS) currently is the most accurate test in the local-regional staging of gastric cancer. Advanced gastric cancers should be staged with a combination of EUS and computed tomography (CT). Local therapy can be appropriately applied to early gastric cancers that have no nodal involvement and are limited to the muscularis mucosa. The additional use of EUS-fine-needle aspiration (FNA) for lymph nodes distant from the primary tumor may improve staging accuracy. [ABSTRACT FROM AUTHOR]

Gastric polyps are a frequent incidental finding during endoscopy that occasionally present with bleeding, obstruction, or pain. The majority are non-neoplastic. The major epithelial polyps are fundic gland, hyperplastic, and adenomatous. Sporadic fundic gland polyps (FGPs) are benign and have no malignant potential. Hyperplastic and adenomatous polyps may arise in a background of Helicobacter pylori infection and have malignant potential; these should be endoscopically removed. Gastric polyps can also be seen as a manifestation of polyposis syndromes most notably familial adenomatous polyposis (FAP; FGPs and to a lesser degree adenomatous), Peutz Jegher's syndrome (harmatomas), and juvenile polyposis (hamartomas). Patients with familial polyposis may be at an increased risk of gastric cancer, particularly those with Peutz-Jegher's syndrome. Endoscopic polypectomy is safe and effective but carries a higher complication rate than polypectomy in the colon. [ABSTRACT FROM AUTHOR]

Despite therapy, most patients diagnosed with esophageal cancer in 2004 will die from their disease. Surgery and radiation have been the historical treatments of choice for esophageal cancer. However, in an effort to improve outcome, combination therapies have emerged with concurrent chemoradiotherapy, neoadjuvant chemotherapy and chemoradiotherapy, and adjuvant chemotherapy and chemoradiotherapy. Strong proponents for specific individual therapeutic approaches exist, as does controversy because no optimal treatment plan for esophageal cancer has clearly emerged. [ABSTRACT FROM AUTHOR]

Dysplasia is the precursor lesion for the development of carcinoma throughout the gastrointestinal tract. Certain conditions, which may lead to the occurrence of dysplasia, are labeled precursor conditions. The most readily identified such condition is Barrett's esophagus. All esophageal adenocarcinoma follows the sequence of intestinalized Barrett's epithelium progressing to dysplasia and subsequently to adenocarcinoma with relatively measurable frequencies. Gastric dysplasia, however, is usually found in the setting of chronic atrophic gastritis. Unlike the Barrett's lesion, there are no gross endoscopic features or a demarcated anatomic location. Furthermore, patients with Barrett's esophagus are at about the same risk for progression to cancer irrespective of ethnicity, environment, and socioeconomic status. However, these are all important factors contributing to gastric cancer risk in patients with atrophic gastritis. Finally, the symptoms of gastro-esophageal reflux characterize the population at risk for Barrett's, but there are no symptoms attributable to the development of chronic atrophic gastritis (CAG). This chapter reviews the premalignant gastric lesions and their management. [ABSTRACT FROM AUTHOR]

Radiological imaging of the upper gastrointestinal (GI) tract provides useful diagnostic information regarding a wide variety of benign and malignant tumors. Whereas computed tomography (CT) scanning may detect larger invasive tumors and provide information regarding lymphatic and distant metastases, properly done barium studies provide more detail regarding mucosally based or intramural lesions. This chapter reviews the radiological findings of the various benign and malignant tumors of the esophagus and stomach. [ABSTRACT FROM AUTHOR]

Esophageal cancer is currently the ninth leading cause of cancer death in the United States, and since the 1970s, the incidence of esophageal adenocarcinoma has been rising at an alarming rate (1). The National Cancer Institutes estimates 14,250 new cases of esophageal cancer and 13,300 deaths owing to esophageal cancer in 2004. The estimated 5-yr mortality rate remains at 5-10% (1). [ABSTRACT FROM AUTHOR]

The major medical consequence of Barrett's esophagus (BE) is the potential risk of development of esophageal adenocarcinoma. It is the management of this cancer risk and early cancers that is the focus of endoscopic therapies. As the risk of cancer increases, the types of endoscopic therapies that can be applied become more invasive. These therapies involve removal of the esophageal mucosa and portions of the submucosa, thermal therapies to cauterize the neoplastic tissue, and the use of photochemical therapies that cause localized tissue necrosis. Case series suggest that these treatments are effective and in selected patients can be used in lieu of surgery or in patients who are not surgical candidates. However, randomized controlled trials are lacking. [ABSTRACT FROM AUTHOR]

Endoscopy altered the practice of gastroenterology by providing nonoperative access to the gastrointestinal (GI) tract and the pancreaticobiliary system. The detection of microscopic and biochemical changes within the mucosa and submucosa, however, has remained beyond the realm of routine endoscopy. Distinguishing hyperplastic from neoplastic polyps, differentiating malignant from benign ulcers, and detecting mucosal dysplasia in patients with inflammatory bowel disease or Barrett's esophagus (BE) remains within the purview of the GI pathologist. In particular, endoscopic detection of dysplasia relies on the recognition of visible lesions (e.g., adenomatous polyps, dysplasia-associated lesion, or mass), or random sampling of tissue (biopsy). Endoscopy alone can neither reliably detect regions of invisible or flat dysplasia nor distinguish dysplasia from nondysplastic changes within visible lesions. Histological examination of the excised material is required to diagnose and locate dysplasia. Random biopsy techniques are subject to sampling errors and increased risk because of long procedure time and multiple biopsy sites. In patients with inflammatory bowel disease, it has been estimated that a total of 33 and 56 biopsy specimens are required for a 90 and 95% confidence to detect dysplasia or carcinoma (1). [ABSTRACT FROM AUTHOR]

Esophageal carcinoma is the fifth most common gastrointestinal cancer, and the recent data suggests that it is rising in incidence faster than any other malignancy. Although esophageal carcinoma is generally felt to have a poor prognosis, this is largely owing to the heterogeneity of patients. As with any malignancy, the stage of the tumor predicts prognosis and determines treatment options. Stage of the tumor at diagnosis is the best predictor of long-term survival. Patients with early or localized disease may have excellent survival when treated surgically, whereas patients with more advanced disease may not. Multimodality chemoradio-therapy plus surgery may optimize survival. Patients with invasion into adjacent structures or distant metastatic disease are more appropriately treated with palliation alone. Every patient with esophageal carcinoma should be clinically staged to determine which treatment options are appropriate and to individualize management. Clinical stage can be accurately determined by a combination of modern staging techniques including computed tomography (CT), esophagogastroduodenoscopy (EGD), endoscopic ultrasonography (EUS), positron emission tomography (PET), and minimally invasive surgery. [ABSTRACT FROM AUTHOR]

Although the relative incidence of esophageal squamous cell carcinoma (SCC) has been declining steadily in the United States and Europe compared to that of adenocarcinoma (1,2); esophageal SCC continues to be the more common form of esophageal malignancy worldwide (3). There are approx 6000 new cases of esophageal SCC diagnosed in the United States annually (4). The global incidence and gender ratio vary widely according to geographic region, likely reflecting environmental and dietary factors more than genetic predisposition. Several risk factors for esophageal SCC have been identified, making screening a potential option for specific populations. This chapter outlines conditions or behaviors that are strongly associated with this malignancy, describes methods for improving the endoscopic detection of early squamous cell dysplasia, and suggests specific instances in which screening for esophageal SCC may be appropriate. [ABSTRACT FROM AUTHOR]

Barrett's esophagus (BE) or columnar lined esophagus, is an acquired condition associated with chronic gastro-esophageal reflux disease (GERD). BE is strongly associated with GERD. Numerous endoscopic studies have demonstrated high rates of BE in patients with chronic GERD (1-3). It is a condition in which the normal stratified squamous epithelium of the tubular esophagus is replaced by a metaplastic columnar epithelium. The overriding concern for patients with BE is its malignant potential. BE is accepted as the precursor in most cases of esophageal adenocarcinoma. This malignancy has been linked to chronic GERD and obesity as has BE (4,5). Three case-control studies have demonstrated a strong association between adenocarcinoma of the esophagus and GERD (7-7). The incidence of this malignancy has been rising at a rate of 5-10% for the past three decades in western Europe and the United States, faster than any nondermatological malignancy (8). The Surveillance, Epidemiology, and End Results registry noted more than a 100% increase in the incidence of this tumor between 1976 and 1987 (9). The increasing incidence of esophageal adenocarcinoma appears to be continuing (10). [ABSTRACT FROM AUTHOR]