Identification of factors predictive of malignancy in patients with atypical biliary brushing results obtained via ERCP

Biliary brushings obtained during ERCP can have one of three cellular interpretations: benign, malignant, or "atypical." Atypical interpretations usually result in further testing, and may cause controversy over management and increases in cost. We evaluated a large cohort of patients with atypical biliary brushings for analysis and risk stratification. All biliary brushing specimens collected between January 1, 2001 and December 31, 2010 that had an atypical result were included. Hospital electronic records were reviewed for these patients to include: demographics, indication for ERCP, endoscopist/pathologist impressions, serologic testing, stricture site, and information relating to the final clinical diagnosis. Eighty-six patients were included. Totally, 60/86 patients (70%) had malignancies while 26/86 (30%) had no evidence of malignancy during long term follow up. Univariate analysis showed that the risk of malignant outcomes was significantly associated with older age, suspicious/malignant endoscopic impression, pancreatic mass, indications including jaundice and/or dilated bile ducts, stricture location within the common bile duct, PSC, and CA 19-9 levels >300 U/mL. We created a novel scoring system for prediction of malignancy based on clinical and endoscopic factors. We identified parameters that are typically available to the clinician to categorize patients with an "atypical" bile duct brushing results into "high risk" and "lower risk" classifications. Our proposed scoring system would allow such risk stratification to take place.

Methods specification for diagnostic test accuracy studies in fine-needle aspiration cytology: a survey of reporting practice

Diagnostic test accuracy (DTA) studies on fine-needle aspiration cytology (FNAC) often show considerable variability in diagnostic accuracy between study centers. Many factors affect the accuracy of FNAC. A complete description of the testing parameters would help make valid comparisons between studies and determine causes of performance variation. We investigated the manner in which test conditions are specified in FNAC DTA studies to determine which parameters are most commonly specified and the frequency with which they are specified and to see whether there is significant variability in reporting practice. We identified 17 frequently reported test parameters and found significant variation in the reporting of these test specifications across studies. On average, studies reported 5 of the 17 items that would be required to specify the test conditions completely. A more complete and standardized reporting of methods, perhaps by means of a checklist, would improve the interpretation of FNAC DTA studies.

Decreased colorectal cancer and adenoma risk in patients with microscopic colitis

INTRODUCTION

Microscopic colitis is currently considered to harbor no increased risk for colorectal cancer, based on a few small studies with limited long-term follow-up. Our aim was to identify patients with microscopic colitis, and to compare long-term rates of colorectal cancer or adenoma to a control group of patients without microscopic colitis.

METHODS

We reviewed the records of patients diagnosed with microscopic colitis, as identified by a hospital-based pathology database from January 2000 to August 2008. Clinical factors, including history of adenoma or adenocarcinoma, and all colonoscopy findings, were recorded. Age and gender-matched patients without microscopic colitis served as the control in a 1:1 fashion.

RESULTS

A total of 647 patients (153 male: 494 female) were identified with microscopic colitis (MC). Any history of colorectal cancer was detected in 1.92, 1.81, and 4.17% of patients with collagenous colitis (CC), lymphocytic colitis (LC), and controls, respectively (P = 0.095, P = 0.040, P = 0.015 for CC, LC, and all MC, respectively, comparing to controls). Overall, covariate-adjusted risk (odds ratio) of any history of colorectal cancer and colorectal adenoma in MC patients was 0.34 (95% confidence interval [CI] 0.16-0.73, P = 0.006) and 0.52 (95% CI 0.50-0.76, P < 0.0001), respectively. The mean duration of follow-up was 4.63 years, with 147/647 (22.7%) of patients with clinical follow-up >7 years.

CONCLUSIONS

In this case-control study involving a large retrospective cohort, microscopic colitis is negatively associated with the risk for colorectal cancer and adenoma. Further studies are required to determine a temporal relationship between microscopic colitis and the future development of colorectal neoplasia.

Extraneous tissue: a potential source for diagnostic error in surgical pathology

"Floaters" represent a potential cause of diagnostic error and may arise during tissue processing and slide preparation. Our objective was to determine the frequency of floaters in slides and features useful in their recognition. We reviewed quality assurance (QA) records for floaters in slides and prospectively examined 1,000 additional slides for floaters and documented floater size, location, and presence in 1 or more sections. In the 521,661 slides reviewed for QA, 65 floaters were detected: 28 were present in the tissue block, and 37 were found only in a single level. In the 1,000 prospectively examined slides, 12 floaters were detected; 9 were only in a single section. Floaters represent a potential source of diagnostic error and occur in 0.01% to 1.2% of slides. Pick up of floaters from the water bath appears most common (∼60%). Floaters in only 1 level and mismatch with the specimen tissue type are clues to the extraneous nature of the floater.

Effect of emulsion concentration on biodistribution of perflubron in tumor-bearing mice

Perflubron (perfluoroocytlbromide, PFOB) emulsion concentrations of 100%, 90%, or 60% w/v were administered to mice with and without 3 types of murine malignant tumor implants, and the distribution in blood, tumor, lung, liver and spleen were studied 48 hours after a dose of 10 or 3 g/Kg of PFOB. The most important changes were seen in the blood where the PFOB concentration [PFOB] was decreased in tumor bearing mice (TBM). Blood [PFOB] was also decreased in TBM and normal mice (NM) that received the 60% emulsion. Liver [PFOB] was increased in TBM. Lung [PFOB] was directly proportional to the emulsion concentration with the 10g/Kg dose. No major differences were seen in the biodistribution between the 100% and 90% emulsions using 10g/Kg, in spite of differences in composition and manufacturing history.

Cyclooxygenase inhibition with ibuprofen: effect on biodistribution of perflubron emulsions in mice with mammary tumor

The biodistribution of Perflubron (perfluorocytylbromide, PFOB) was studied by infusing 10 or 3 g/Kg doses of 90% and 100% w/v emulsions into Balb C mice with and without malignant mammary tumor implants. PFOB concentrations were measured in blood, liver, spleen, lung and tumor, and X-rays were taken 48 hours after infusion. Ibuprofen (IBU) was given intraperitoneally 10 mg/Kg dialy for 3 days to study the effects of cyclooxygenase blockade. The results showed that the blood [PFOB] in tumor-bearing mice (TBM) was only 3.6% of that measured in normal mice (NM), and the liver [PFOB] was increased by 59%. The lung [PFOB] increase with IBU therapy in NM was highly significant. IBU therapy resulted in a 98% and 468% increase in blood [PFOB] in normal and TBM, respectively. Smaller but statistically significant changes occurred in blood [PFOB] with saline and sham injections. Tumor [PFOB] was lower by 17% (P = .028) in mice treated with IBU. Smaller decreases were seen with saline and sham injections but did not achieve statistical significance. In conclusion, the presence of this malignant tumor resulted in changes that might influence the usefulness of PFOB as a contrast agent and as an adjuvant for radiation and chemotherapy. This study shows that cyclooxygenase inhibition significantly modified the pharmacodynamics of PFOB emulsions in blood, tumor and lung. The changes seen in the saline placebo and sham category were attributed to stress from procedures.

Uptake of iopanoic acid and its glucuronide conjugate by rat hepatocytes in primary culture

Uptake of iopanoic acid (IOP) and iopanoate glucuronide (IOP-G) was studied in 3-day primary cultures of rat hepatocytes isolated by the collagenase perfusion method. 125I activity of cells after incubation with 125I-IOP (10-100 microM) and 125I-IOP-G (10-100 microM) was used as a measure of uptake. At each concentration, uptake was linear for the first 45 sec. In the absence of albumin, the initial uptake velocity was directly proportional to the concentration or IOP or IOP-G and was nonsaturable up to 100 microM. The calculated uptake rate constants for IOP and for IOP-G were 0.059 and 0.048 nmole/(mg protein X min X microM), respectively. IOP uptake was not inhibited by sodium taurocholate nor by the contrast agents iodipamide, ipodate, and iopronic acid. The data indicate that the enhancement of IOP excretion by bile salts noted in vivo does not occur at the uptake step and that the hepatic uptake of both IOP and IOP-G in the absence of albumin is limited by diffusion.

Uptake of iopanoic acid by isolated rat hepatocytes in primary culture

Uptake of iopanoic acid (IOP) was studied in 3-day primary cultures of rat hepatocytes isolated by the collagenase perfusion method. 125I activity of cells after incubation with 125I-IOP (1.0-100 microM) was used as a measure of uptake. At each IOP concentration uptake was linear for the first 45 s. The initial uptake velocity was directly proportional to IOP concentration and was nonsaturable up to 100 microM. The calculated uptake rate constant was 0.67 nmol . mg prot-1 . min-1 . microM-1. Uptake was only slightly reduced when the incubation was performed at 4 degrees C and was independent of sodium concentration. Albumin in the medium reduced IOP uptake. Uptake, however, was always greater than that predicted from the unbound IOP concentration alone. The data indicate that the hepatocyte uptake of IOP occurs by both a passive process and a saturable process. The saturable uptake component depends on an albumin-IOP-hepatocyte interaction. The influence of albumin on uptake occurs possibly by an undefined specific cell surface phenomenon of albumin that promotes uptake of IOP or by enhancement of the diffusibility of IOP across the unstirred layer.

The potential of iosulamide meglumine as a contrast material for intravenous cholangiography: an experimental study in dogs

Because of relatively low acute toxicity, iosulamide meglumine has been recommended as an improved contrast material for intravenous cholangiography. It has been postulated that high doses of the compound could be given safely with the expectation of achieving greater biliary excretion and improved opacification of the biliary tree. Experiments performed in dogs show that higher rates of infusion of iosulamide result in greater urinary elimination without additional biliary excretion. Consequently, iosulamide is unlikely to have any special advantage as a contrast agent.