Radiology-Pathology Conference: Colonic schwannoma.

We report the radiology and pathology findings on a patient with colonic schwannoma, and review the literature on this very rare tumor.

Radiology-pathology conference. Acinar cell carcinoma of the pancreas.

Acinar cell carcinoma (ACC) is a rare tumor that constitutes 1% of pancreatic neoplasms. ACC is defined as a carcinoma exhibiting pancreatic enzyme production by neoplastic cells. Clinical presentation is usually related to either local spread or metastasis. In this Radiology-Pathology Conference, the clinical presentation and imaging findings of a patient with ACC of the pancreas, along with the differential diagnosis, are reviewed.

Complications of abdominal and pelvic procedures: computed tomographic diagnosis.

The postprocedural period is a critical time in which serious complications can manifest. Localization of suspected complications following abdominal and pelvic procedures can be difficult on clinical evaluation alone. For example, abdominal pain after a colonoscopy may vary in etiology and can result from simple colonic spasm to colonic perforation, hemoperitoneum, or even splenic rupture. Vague abdominal pain following a renal biopsy may be due to minimal postprocedural bleeding into and around the kidney or may be due to potentially life-threatening hemorrhage. In such patients, computed tomography can play a crucial role in the rapid identification of complications as well guidance of subsequent patient management. The purpose of this article is to demonstrate the benefit of computed tomography-assisted diagnosis of complications associated with routine procedures performed on or throughout the abdomen and pelvis, including cardiac catheterization, colonoscopy, endoscopy, percutaneous biopsy, and interventional radiology procedures.

Radiology-Pathology Conference: carcinosarcoma of the colon.

Carcinosarcomas are very uncommon tumors, which are comprised of both malignant epithelial and mesenchymal elements. They occur most commonly in the head and neck, respiratory tract, and female reproductive organs. In the gastrointestinal tract, they are most often found in the oropharynx, esophagus, and, to a lesser extent, in the stomach. Carcinosarcomas rarely originate from the colon, but when they do, they are extremely aggressive malignancies. We report the radiologic and pathologic findings of a patient with a carcinosarcoma believed to have arisen from the colon and which involved the adjacent mesentery and omentum.

Correlation of paired liver biopsies in morbidly obese patients with suspected nonalcoholic fatty liver disease.

In the absence of surrogate markers, the evaluation of suspected nonalcoholic fatty liver disease (NAFLD) is highly dependent on histological examination. The extent of sampling variability affecting the reliability of a single liver biopsy in patients with suspected NAFLD is poorly characterized. This prospective study aimed to correlate precise histological findings in paired biopsies--right and left lobe--in the diagnosis of NAFLD in morbidly obese subjects undergoing bariatric surgery employing both Brunt and Matteoni classifications and the NAFLD Activity Score (NAS). We also aimed to determine whether the composite histopathological findings of the two biopsies would improve diagnostic accuracy. Consecutive subjects had an intraoperative biopsy from both right and left lobes, evaluated and scored in a blinded manner. Intraobserver agreement was also assessed. Kappa coefficients of agreement were calculated. Forty-one subjects had acceptable biopsies. Agreement for steatosis was excellent and moderate for fibrosis. Concordance was only fair for most features of necroinflammation. Intraobserver agreement was only moderate for lobular inflammation. Excellent agreement was seen for the diagnosis of NASH using Brunt criteria and good agreement when using Matteoni and NAS scoring systems. Composite biopsy data particularly improved identification of hepatocyte ballooning. The diagnostic accuracy also improved substantially when composite features were compared with single-sided biopsy features, especially for the Matteoni and NAS scoring systems. In conclusion, significant sampling variability occurs in NAFLD, particularly for features of necroinflammation. This should be factored into the design of clinical trials and studies of the natural history of the disease.

Racial and ethnic distribution of nonalcoholic fatty liver in persons with newly diagnosed chronic liver disease.

We performed a cross-sectional study of newly diagnosed cases of nonalcoholic fatty liver disease (NAFLD) identified between December 1998 and December 2000 in the Chronic Liver Disease Surveillance Study. We compared the demographic and clinical features of NAFLD in a racially diverse representative U.S. population (Alameda County, CA). Diagnostic criteria for probable NAFLD were persistent unexplained elevation of serum aminotransferase levels, radiology (ultrasound or computed tomography scan) consistent with fatty liver, and/or two or more of the following: (i) body mass index of 28 kg/m(2) or more, (ii) type 2 diabetes, or (iii) hyperlipidemia, in the absence of significant alcohol use. Definite NAFLD cases required histological confirmation. Of the 742 persons with newly diagnosed chronic liver disease, 159 (21.4%) had definite or probable NAFLD. The majority were nonwhite: Hispanics (28%), Asians (18%), African Americans (3%), and other race(s) (6%). African Americans with NAFLD were significantly older than other racial or ethnic groups (P < .001), and in Asians, NAFLD was 3.5 times more common in males than in females (P = .016). Clinical correlates of NAFLD (obesity, hyperlipidemia, diabetes) were similar among racial and ethnic groups, except that body mass index was lower in Asians compared with other groups (P < .001). Compared with the base population (Kaiser Permanente members), Hispanics with NAFLD were overrepresented (28% vs. 10%) and whites were underrepresented (45% vs. 59%). In conclusion, these racial and gender variations may reflect differences in genetic susceptibility to visceral adiposity, including hepatic involvement, and may have implications for the evaluation of persons with the metabolic syndrome. Clinicians need to be aware of the variable presentations of NAFLD in different racial and ethnic groups.

Comparison of the cost and effectiveness of two strategies for maintaining hepatitis B immunity in hemodialysis patients.

A decision-analysis model was developed to compare the strategies to maintain hepatitis B virus (HBV) immunity in hemodialysis patients who responded to the primary HBV vaccine. Our hypothesis is that the routine, annual administration of the vaccine booster to all hemodialysis patients (non-screening strategy) is more cost-effective than the current strategy of vaccination based on anti-HBs titers (screening strategy). Under baseline assumptions, the screening strategy was less costly and was associated with fewer HBV infections than the non-screening strategy. The results of our model did not support our hypothesis, and indicate that regularly screening patients for HBV immunity before revaccination is less costly and more effective than the empiric vaccination of hemodialysis patients.

Hepatitis C-positive donors in heart transplantation.

Hepatitis C virus (HCV) can be transmitted to heart transplant recipients by donor organs. Mid-term results were reported using HCV-positive donors in patients at risk of imminent death (group I, n = 10), or in patients who otherwise would not have been offered heart transplantation (group II, n = 10) because of age (9/10) or associated medical risk (1/10). Medical records pertaining to patients receiving HCV-positive allografts between July 1994 and December 1999 were reviewed. The recipients consisted of 19 males and one female, with a median age of 54 years for group I and 66 for group II. The HCV RNA level, seroconversion of anti-HCV antibody, biochemical liver dysfunction, and causes of death were examined. Older recipients received reduced immunosuppression. Two patients in group II were HCV positive and were also retransplants. The hospital mortality rate was 10% in group I and 20% in group II; both hepatitis C-positive recipients died postoperatively prior to discharge. All predischarge deaths were related to multi-system organ failure (MSOF). All 17 survivors were HCV negative prior to transplant. Of these, 4/17 seroconverted. HCV RNA was detected in two of them. At a median follow-up of 26.4 months, 2/11 current survivors continue to test anti-HCV positive and are RNA negative. Three-year actual survival was 40% for group I and 70% in group II. Transplant coronary artery disease (TCAD) accounted for one postoperative death in group I. Current data show that four out of 11 survivors had developed TCAD at 3-year follow-up, yielding an actual freedom from TCAD rate of 12/17 (70%) at 3-year follow-up. Hepatitis C transmission using a donor heart as the reservoir is moderate (25%). Limited use of such donors is justified in selected patients. The risk for hepatic disease may be reduced by tailoring immunosuppression specifically for such recipients, particularly if they are at low risk of rejection. Further studies are necessary to define a possible association between HCV and TCAD.