Carcinoid tumors of the stomach: a clinical and radiographic study.

OBJECTIVE: Our purpose is to describe associated and coexistent diseases of gastric carcinoid tumors, the unique biologic behavior of these tumors, the appearance of these tumors on fluoroscopic and CT images, and the radiologic management of these neoplasms. CONCLUSION: First, multiple gastric carcinoid tumors are associated with enterochromaffin-like cell hyperplasia, chronic atrophic gastritis, and pernicious anemia and have a low risk of malignancy. Second, solitary gastric carcinoid tumors, or gastric carcinoid tumors associated with multiple endocrine neoplasia-type I (MEN-I) and Zollinger-Ellison syndrome, have a higher potential for metastatic disease. Third, the radiologic appearance and management of these tumors depend on the clinical background of the patient.

Candida jejunitis: a rare cause of intestinal pneumatosis in the immunocompromised patient.

A case of fatal necrotizing jejunitis caused by Candida albicans is described in a patient with acute myeloid leukaemia undergoing chemotherapy. The diagnosis was made at autopsy. Computed tomography findings were of small bowel dilatation with pneumatosis.

Renal cell carcinoma metastatic to the pancreas: clinical and radiological features.

OBJECTIVE: To review the clinical features, computed tomographic (CT) appearance, and treatment outcomes in a case series of patients with renal cell carcinoma (RCC) metastatic to the pancreas. PATIENTS AND METHODS: We retrospectively reviewed the records of 23 patients (15 men and 8 women) with RCC metastatic to the pancreas, detected by CT examination between 1986 and 1996. All patients had undergone a previous nephrectomy for RCC. RESULTS: Isolated mild elevation in liver function test results (in 5 patients) or in serum amylase level (in 8 patients) was observed. New-onset diabetes was detected in 3 patients. The CT characteristics of the pancreatic metastases generally resembled those of primary RCC with well-defined margins and greater enhancement than normal pancreas with a central area of low attenuation. The mean interval between resection of the primary RCC and detection of the pancreatic metastases was 116 months (range, 1-295 months). In 18 patients (78%), the pancreatic metastases were diagnosed more than 5 years after nephrectomy. The pancreas was the initial metastatic site in 12 patients (52%). Survival was shortened with higher tumor grade (mean survival time of 41 months and 10 months in patients with grade 2 and 3, respectively). Surgical resection was carried out in 11 patients (7 distal and 3 total pancreatectomies and 1 distal pancreatectomy followed 4 years later by total pancreatectomy), with 8 patients alive at a mean follow-up of 4 years, 6 of whom remained free of recurrence. Overall, 12 patients (52%) were alive at a mean of 42 months after diagnosis of metastatic disease. CONCLUSIONS: The appearance of metastatic RCC lesions in the pancreas closely resembles the appearance of primary RCC on CT images. Pancreatic metastases from RCC are frequently detected many years after nephrectomy. Patient survival correlates with tumor grade. Histologic analysis of pancreatic masses in patients with a history of resected primary RCC is important since the prognosis for RCC metastatic to the pancreas is much better than that for primary pancreatic adenocarcinoma.

Chemotherapy-related hepatotoxicity causing imaging findings resembling cirrhosis.

In this article, we describe three women in whom changes in the liver resembling cirrhosis occurred during systemic chemotherapy for metastatic breast carcinoma. All three patients were treated with tamoxifen as part of their chemotherapeutic regimen. Abnormalities of biochemical liver tests were associated with the development of a cirrhosis-like appearance of the liver on computed tomography. In two of the patients, hepatic metastases were proved at biopsy. The third patient had no radiologic evidence of metastatic disease. Chemotherapy for metastatic breast carcinoma may cause striking morphologic changes in the liver that resemble cirrhosis. Of importance, these changes should not be mistaken for the development or progression of liver metastases. Alternatively, because of the changes produced by chemotherapeutic agents, detection of metastases on computed tomography alone may be more difficult. Supplementary magnetic resonance imaging may be helpful in selected cases.

CT characteristics of metastatic disease of the pancreas.

Contrast material-enhanced computed tomographic (CT) scans obtained over a 10-year period in 66 patients with metastases to the pancreas were retrospectively reviewed. The primary tumors most commonly responsible for these metastases were renal cell carcinoma (30.3%) and bronchogenic carcinoma (22.7%). Metastases showed no predilection for any particular part of the pancreas. The majority (75.8%) of metastases appeared as tumors with discrete margins, and most of these tumors were round or ovoid with smooth borders. Over three-fourths of the lesions demonstrated enhancement (usually heterogeneous). Vascular involvement was uncommon. In those patients in whom pancreatic metastases were discovered some time after the primary tumor was identified, the interval ranged from 2 to 295 months, with the longest mean interval (120.2 months) being associated with metastatic tumors from renal cell carcinoma. The appearance of these tumors at CT--predominantly hyperattenuating masses, often with nonenhancing internal components--was similar to that of primary renal cell carcinoma. In most pancreatic metastases, however, clinical information in conjunction with CT characteristics such as multiplicity of tumors or hypervascularity permit differentiation of metastases from primary neoplasm. When diagnosis of a pancreatic neoplasm is uncertain, percutaneous biopsy often permits histologic confirmation of the tumor type.

CT of pancreatic neoplasms. Part I: Adenocarcinoma.

Adenocarcinoma of the pancreas has been one of the most formidable, diseases of the past half century, consistently ranking among the leading causes of death from cancer in the industrialized world. The profound diagnostic difficulties that characterized this neoplasm during the early decades of that era have largely given way to radiologic advances of recent decades. Daunting therapeutic challenges persist, however, as few individuals in whom this common form of pancreatic cancer develops are aware of their illness before the disease has advanced beyond the stage of curability. The benefits of recent diagnostic break-throughs in pancreatic adenocarcinoma are nonetheless immense. Although their proportion remains disappointingly small, an increasing number of persons owe their lives to the detection of pancreatic carcinoma at a stage amenable to complete surgical resection. Far more patients benefit from timely detection, accurate staging, and nonsurgical biopsy of an unresectable neoplasm. Still more, perhaps, benefit from the confident exclusion of pancreatic cancer as a source of worrisome symptoms. The goal of this discussion is to help the radiologist achieve full diagnostic potential in examining patients who have, or who are suspected to have, adenocarcinoma of the pancreas. As the leading method in the diagnostic advance on pancreatic cancer, computed tomography (CT) is given predominant attention. The principles of diagnostic interpretation, however, are based on an understanding of the neoplasm itself. In that respect, the manifestations of pancreatic adenocarcinoma as displayed by CT are in large measure just as pertinent to any other worthwhile method of pancreatic imaging.

CT of pancreatic neoplasms. Part II: The unusual tumors.

The pancreas gives rise to a remarkable variety of neoplasms other than ductal adenocarcinoma. Although no individual type of tumor in this category is prevalent enough to qualify as common, most types are currently encountered with a frequency far greater than that in decades of the recent past. This change is largely the result of the expanded use of contemporary abdominal imaging. The unusual tumors of the pancreas vary greatly in their biologic behavior and, accordingly, in their clinical consequences and therapeutic requirements. Accurate diagnosis, therefore, can be of considerable clinical relevance. Not only is it worthwhile to distinguish one type of unusual pancreatic tumors from another, it is perhaps of even greater consequence to distinguish the unusual tumors from ordinary pancreatic adenocarcinomas. The goals of this discussion are to expand radiologic awareness of these uncommon but interesting pancreatic neoplasms and to increase familiarity with their diagnostically salient features.

Gastric carcinoid tumors associated with chronic hypergastrinemia in a patient with Zollinger-Ellison syndrome.

A patient with long-standing Zollinger-Ellison syndrome, treated for 14 years with antisecretory agents, underwent computed tomography and upper gastrointestinal examination because of upper gastrointestinal bleeding. Radiologic and pathologic examinations showed multiple nodular masses arising from the wall of the stomach that were determined to be mucosal carcinoid tumors. A gastrin-producing islet cell tumor of the pancreatic head was also present. Gastric carcinoid tumors occurred as a consequence of chronic hypergastrinemia.

Celiac plexus block. Retrocrural computed tomographic anatomy in patients with and without pancreatic cancer.

BACKGROUND AND OBJECTIVES: Neurolytic celiac plexus block is often performed for analgesia from pancreatic cancer, but it is not known if the cancer alters the anatomy relevant to the successful performance of retrocrural celiac plexus block. METHODS: Abdominal computed tomographic scans were used to simulate retrocrural celiac plexus block in patients with and without pancreatic cancer. RESULTS: Simulated right-sided needle placement in the retrocrural space was more likely to fail in patients with pancreatic cancer than in patients without cancer. Such predicted failure often occurred when the cross-sectional area of the right retrocrural space was less than 1.0 cm2. CONCLUSIONS: The predicted success of stimulated retrocrural celiac plexus block differed between patients with and without pancreatic cancer. These findings have implications for the performance of celiac plexus block.

Barium enema: detection of colonic lesions in a community population.

OBJECTIVE: The purposes of this study were to assess the prevalence of colonic lesions detected at barium enema in a community practice, to compare the findings at barium enema between patients who are asymptomatic and have no known risk factors for colorectal cancer (screening group) and patients who have symptoms of colonic disease or have known risk factors, and to determine if a questionnaire about symptoms and risk factors is an appropriate screening tool. SUBJECTS AND METHODS: A self-administered questionnaire about colorectal symptoms and risk factors was given to 1779 patients scheduled for barium enema examination. On the basis of their responses, patients were divided into three groups: screening group (asymptomatic, without risk factors), symptomatic, and asymptomatic with risk factors. Each patient underwent a fluoroscopic barium enema. We then compared the results (number, histologic type, size of lesion(s), location in the colon, and Patient's age) and risk factors among the three groups. RESULTS: At least one lesion within the colorectum was found in 166 (9%) of 1779 patients at combined proctosigmoidoscopy and barium enema. The prevalence of lesions in the 111 patients with at least one lesion above the rectum at barium enema was 4% (32 of 738) for the screening group, 8% (38 of 476) for asymptomatic patients with risk factors, and 7% (41 of 565) for symptomatic patients (p = .015 when comparing the prevalence in the screening group with the prevalences in the other two groups). Twenty-nine percent of all colonic lesions were found in the screening group. Among the asymptomatic patients, risk factors that included a history of colorectal polyps and advanced age were associated with a significantly higher prevalence of colonic polyps found at barium enema. In the symptomatic group, if patients with histories of polyps were excluded, we were unable to identify other risk factors that led to a significantly higher prevalence of polyps. CONCLUSION: Asymptomatic patients without known risk factors have a significantly lower prevalence of colonic polyps than either symptomatic patients or patients with risk factors alone. Despite this lower prevalence, 29% of all lesions in our series were in the screening group. Assessment of risk factors through a patient questionnaire was not helpful in identifying a group of patients with a higher prevalence of lesions--except for a history of polyps. Management decisions based on a patient questionnaire should be approached with caution. When low-risk patients are denied screening examinations, a significant number of lesions will be missed.

Intraductal papillary-mucinous tumors of the pancreas: clinicopathologic features, outcome, and nomenclature. Members of the Pancreas Clinic, and Pancreatic Surgeons of Mayo Clinic.

BACKGROUND & AIMS: Intraductal papillary-mucinous tumor (IPMT) of the pancreatic ducts is increasingly recognized. This study investigated if clinical, imaging, or, histological features predicated outcome, formulated a treatment algorithm, and clarified relationships among IPMT, mucinous cystic neoplasms of the pancreas (MCN), and chronic pancreatitis. METHODS: The medical records, radiographs, and pathological specimens of 15 patients with IPMT (dilated main pancreatic duct or branch ducts with mucin overproduction) who were evaluated between October 1983 and January 1994 were reviewed. RESULTS: One patient had hepatic metastases. Fourteen underwent an operation (6 distal pancreatectomy, 4 total pancreatectomy, and 4 pancreaticoduodenectomy); all had dysplastic intraductal epithelium and chronic pancreatitis, whereas 3 had invasive adenocarcinoma. After a median of 25 months, 10 patients were alive; 3 of 4 with malignant and 2 of 11 with benign IPMT died (P < 0.05). Patients with or without carcinoma had similar clinical and radiographic features. A clinical diagnosis of chronic pancreatitis had been made in 9 patients with benign IMPT and in none with malignant IPMT (P < 0.05). CONCLUSIONS: IPMT is a dysplastic and likely precancerous lesion that is frequently diagnosed as chronic pancreatitis and is separate from MCN. Because it is not possible to distinguish noninvasive from invasive IPMT preoperatively, complete surgical excision of the dysplastic process is our treatment of choice whenever appropriate.

Mosaic pattern of hepatocellular carcinoma: histologic basis for a characteristic CT appearance.

PURPOSE: The mosaic pattern is a characteristic CT appearance for hepatocellular carcinoma (HCC). This study was designed to assess the tissue composition responsible for the CT mosaic pattern. METHOD: Gross and whole-mount histologic sections of 10 HCC tumors from eight patients were prepared at identical levels as preoperative CT sections. CT features of the mosaic tumor pattern were spatially registered with the corresponding pathologic sections. RESULTS: CT of mosaic HCC demonstrated enhancing nodules (9/10), low attenuation areas (9/10), and internal septa (3/10). Spatial registration of CT and microscopic sections showed that enhancing tissue was viable tumor in nine of nine. Low attenuation areas were either necrotic (4/9) or of mixed tissue (5/9), including areas of necrosis, fibrosis, and hemorrhage. CONCLUSION: The variable tissue composition of HCC accounts for the mosaic CT pattern. In most patients, enhancing nodules indicate viable tumor cells, and low attenuation areas represent necrosis, fibrosis, or hemorrhage.

Celiac disease: how common is jejunoileal fold pattern reversal found at small-bowel follow-through?

OBJECTIVE: Celiac disease, or nontropical sprue, is a cause of mucosal malabsorption. A decreased number of jejunal folds and an increased number of ileal folds (jejunoileal fold pattern reversal) found at small-bowel follow-through have been reported for patients with celiac disease. We asked three questions regarding jejunoileal fold pattern reversal found at small-bowel follow-through in patients with celiac disease. (1) How often is it present, either partially or completely? (2) How often is it associated with other findings of malabsorption? (3) How reliably can it be distinguished from the normal pattern? MATERIALS AND METHODS: Twenty-eight small-bowel follow-through examinations performed on 25 adult patients with celiac disease (confirmed by characteristic small-bowel biopsy and clinical response to a gluten-free diet) were reviewed retrospectively by two authors, who agreed by consensus on partial or complete jejunoileal fold pattern reversal and on other findings of malabsorption. Two methods were used to control for retrospective bias. (1) The prospective and retrospective readings of fold pattern reversal were compared for agreement. (2) The author who had not participated in the retrospective review was asked to distinguish, on the basis of the presence or absence of fold pattern reversal, 24 cases of celiac disease (all of which showed partial or complete fold pattern reversal on retrospective review) from 25 normal control cases (patients with diarrhea) (conformed by normal small-bowel biopsy). RESULTS: Partial or complete jejunoileal fold pattern reversal was identified retrospectively in 24 of the 28 small-bowel examinations (86%) performed on patients with celiac disease. One-half lacked other findings of malabsorption. The prospective and retrospective readings of fold pattern reversal agreed in 21 of the 28 examinations (75%). Forty-four of 49 examinations (90%) were correctly identified by the third author on the basis of fold pattern reversal. CONCLUSION: In patients with celiac disease, partial or complete jejunoileal fold pattern reversal discovered at small-bowel follow-through is common, is often not associated with other findings of malabsorption, and can be reliably distinguished from the normal pattern. Identification of jejunoileal fold pattern reversal found at small-bowel follow-through should prompt an appropriate clinical evaluation for celiac disease.

Fibrolamellar hepatocellular carcinoma: stage at presentation and results of aggressive surgical management.

OBJECTIVE: The purpose of this study was to report the stage of fibrolamellar carcinoma at presentation and the imaging findings of postoperative recurrent tumor in an aggressively managed population and to assess the implications of those findings relative to the patients' management. MATERIALS AND METHODS: Imaging studies in 10 patients with pathologically proved fibrolamellar carcinoma were reviewed. Preoperative studies included CT (n = 10), sonography (n = 8), and MR imaging (n = 2). Postoperative studies included CT (n = 9), sonography (n = 4), and MR imaging (n = 1). Imaging findings were correlated with clinical and surgical follow-up data. Patients were followed up for 2-75 months (median, 26 months). RESULTS: At presentation, seven (70%) of 10 patients had metastatic lymphadenopathy. Seven patients (70%), including four with lymph node metastasis, had tumor resections with intent to cure. Postoperative imaging studies revealed recurrent tumor in all seven of these patients, including six patients (86%) who had intrahepatic recurrence with or without lymph node metastasis after 6-18 months, and one patient (14%) who had distant metastases 66 months postoperatively. Recurrent lesions were subsequently resected in three (43%) of seven patients, who were disease-free at a mean of 8 months after their second resection. Five patients died after 9 months mean survival, and two patients were alive with residual tumor after 3 months mean follow-up. CONCLUSION: Fibrolamellar carcinomas are often of advanced stage at diagnosis. Recurrence after resection with intent to cure is common. Early and frequent follow-up imaging is necessary for optimizing surgical management in patients with fibrolamellar carcinoma.

Mercury toxicosis caused by ingestion of a blistering compound in a horse.

Mercury toxicosis by ingestion was diagnosed in a 3-year-old Quarter Horse mare with a history of anorexia and signs of abdominal discomfort. Ten and 9 days prior to admission, an inorganic mercuric blistering agent has been applied for topical treatment of dorsal metacarpal disease. At referral, signs of depression, dependent edema, pollakiuria, nonproductive cough, and oral ulceration were noticed. Laboratory data were consistent with renal dysfunction. Mercury content of blood and urine was high, confirming the diagnosis. The horse responded to intensive care, consisting primarily of IV fluid treatment, and mercury-chelating agents. However, acute laminitis developed, and the owners elected to euthanatize the horse 18 days after mercury exposure. Necropsy findings included renal tubulonephrosis and ulcerative colitis and enteritis. Mercury concentration was highest in kidney and liver tissues. The potential for mercury toxicosis in horses currently exists, and although the prognosis is grave, some horses may recover with appropriate treatment and long-term supportive medical care.

Percutaneous adrenal biopsy: review of a 10-year experience.

PURPOSE: To evaluate the indications for and complications, accuracy, and techniques of percutaneous adrenal biopsy performed from 1982 through 1991 at the authors' institution. MATERIALS AND METHODS: Two hundred seventy-seven percutaneous adrenal biopsies were performed in 270 patients (175 male and 102 female patients, aged 31-84 years). Imaging studies and histories were reviewed, and each patient's case was followed up for at least 1 year after the biopsy. A patient was excluded from the study only if follow-up data could not be obtained. RESULTS: The accuracy of percutaneous adrenal biopsy was 90% (249 of 277 biopsies). In the first 5 years of the study, the accuracy was 85% (87 of 102 biopsies); in the latter 5 years it was 93% (163 of 175 biopsies). The sensitivity was 81%, and the specificity was 99%. The positive predictive value was 99%, and the negative predictive value was 80%. The complication rate was 2.8%. CONCLUSION: Percutaneous biopsy is a safe, accurate procedure for the diagnosis of pathologic conditions of the adrenal glands. The most common indication for a biopsy is the presence of an adrenal mass in a patient with lung cancer.

CT findings in hepatocellular carcinoma: correlation of tumor characteristics with causative factors, tumor size, and histologic tumor grade.

PURPOSE: To determine computed tomographic (CT) findings of hepatocellular carcinoma (HCC) in a predominantly non-Asian population and to assess any morphologic differences with respect to causative factors, tumor size, and histologic grade. MATERIALS AND METHODS: Clinical history, pathology reports, histologic specimens, and CT findings in 100 patients with HCC were reviewed. All patients underwent contrast material-enhanced incremental dynamic CT. Findings were agreed on by consensus. RESULTS: The mosaic pattern was seen in 46% of cases, venous invasion in 33%, and tumor encapsulation in 31%; frequencies were similar to those reported with Asian patients. A mosaic pattern was more common in patients with larger tumors (P = .036). Venous invasion was more common in patients with alcohol-induced cirrhosis (P = .003) and in those with higher grade tumors (P = .043). Tumor encapsulation was more common in patients with lower grade tumors (P = .012). CONCLUSION: Reported morphologic differences between non-Asian and Asian patients with HCC may be due to differences in underlying liver disease, tumor size, and histologic grade.

Pancreatic lesions in von Hippel-Lindau disease: prevalence, clinical significance, and CT findings.

OBJECTIVE: The purposes of this study were to determine the nature, prevalence, and CT findings of pancreatic lesions in patients with von Hippel-Lindau disease and to determine whether identification of pancreatic cysts and neoplasms is important in establishing the diagnosis of von Hippel-Lindau disease. SUBJECTS AND METHODS: The medical records and radiologic images of 52 patients with von Hippel-Lindau disease who were evaluated at our institution between 1976 and 1992, and who at some stage underwent abdominal CT, sonography, or MR imaging, were reviewed. The nature, prevalence, and CT findings of the pancreatic lesions were determined, and the role of the pancreatic abnormalities in establishing the diagnosis of von Hippel-Lindau disease was studied. RESULTS: Twenty-nine (56%) of the 52 patients had pancreatic lesions. Nineteen patients had pancreatic cysts and no other pancreatic lesion. Four patients had islet cell tumors only, one had a microcystic adenoma only, and three had indeterminate pancreatic masses. One patient had cysts and an islet cell tumor, and another patient had cysts, an islet cell tumor, and a microcystic adenoma. In six patients (12%), pancreatic lesions were the only abdominal manifestation of von Hippel-Lindau disease. In three patients screened because of a family history of von Hippel-Lindau disease, no CNS abnormalities were present, and the only abdominal lesions were in the pancreas (cysts in two cases, islet cell carcinoma in the other). Thus, the pancreatic lesion was an important factor in establishing a diagnosis of von Hippel-Lindau disease in these patients. CONCLUSION: Pancreatic lesions may be the only abdominal manifestation of von Hippel-Lindau disease. CT findings include cysts, islet cell tumors, and microcystic adenomas. Pancreatic lesions, including cysts, may precede any other manifestation of von Hippel-Lindau disease by several years, and recognition permits earlier diagnosis in patients being screened for von Hippel-Lindau disease.