First in vivo optical coherence tomography in the human bile duct.

BACKGROUND AND STUDY AIMS: Optical coherence tomography (OCT) is a novel technique for performing high-resolution, cross-sectional tomographic imaging in human tissue, which allows resolution of up to 10 microm. The short depth of penetration allows assessment of the superficial 2 mm of the gastrointestinal tract, an area that is difficult to appraise even with high-frequency ultrasound. This is the first report on in vivo OCT of the human biliary system. The aim was to assess the feasibility of the technique. PATIENTS AND METHODS: Four cases of intraductal OCT are presented. The probe was inserted through the working channel of a duodenoscope. RESULTS: The connective tissue layer and the underlying retroperitoneal tissue, with less backscattering, could be clearly demonstrated. The images showed a layer architecture which was similar to that found histologically. CONCLUSIONS: OCT of the biliary system is feasible in patients with biliary pathology. Interpretable images were obtained, and clinical use needs further assessment. As current OCT probes and processors do not yet provide optimal resolution, further generations of equipment with improved image quality are required.

Outcome of endoscopic sphincterotomy in patients with pain of suspected biliary or papillary origin and inconclusive cholangiography findings.

BACKGROUND AND STUDY AIMS: We prospectively studied the outcome of endoscopic sphincterotomy in symptomatic patients with elevated liver enzyme levels but no clear evidence of biliary pathology on transabdominal ultrasound and diagnostic endoscopic retrograde cholangiography (ERC). METHODS: 29 consecutive patients with biliary-type pain (two or more out of eight criteria), elevated liver enzyme levels and no evidence of gallstones or significant common bile duct dilatation were evaluated. Elevated bilirubin levels (up to 7.2 mg/dl) were found in 18 patients. The majority of patients (n = 21) had a gallbladder in situ. The findings from bile duct exploration following sphincterotomy were recorded, and pain (as measured by visual analogue scale) as well as laboratory findings was assessed. RESULTS: Wire-guided sphincterotomy was successful in all patients while uncomplicated pancreatitis occurred in one instance. In 16 patients (55%) there was macroscopic evidence of small stones (n = 2), sludge (n = 12) or both (n = 2) following bile duct exploration. In addition, microscopy showed bile crystals in all four patients who had no macroscopic findings. All four patients with elevation of pancreatic enzymes prior to treatment, and four of those eight patients with previous cholecystectomy, showed evidence of biliary pathology. The initial median pain intensity was 8 (range 1-10); 26 patients became pain-free within 3 months following endoscopic sphincterotomy. While 26 of 28 patients (93%) remained asymptomatic over a median follow-up period of 19 months (range 12-26), one died of an unrelated malignancy 6 months after therapy. CONCLUSIONS: Endoscopic sphincterotomy may be acceptable in patients with typical clinical presentation suggesting a papillary or biliary origin of pain without further diagnostic work-up. Contrary to expectations, diagnostic ERC was insensitive in detection of the biliary etiology of symptoms in this selected group of patients.

Detection of pancreatic metastases by EUS-guided fine-needle aspiration.

BACKGROUND: Metastases to the pancreas are usually found incidentally. Tissue diagnosis is imperative because imaging alone is incapable of differentiating them from primary pancreatic tumors. This study tested whether it is possible to differentiate metastases from other focal pancreatic lesions by using EUS-guided fine-needle aspiration (EUS-FNA) for cytodiagnosis. METHODS: One hundred fourteen consecutive patients (mean age 61 years) with focal pancreatic masses, detected on CT, underwent EUS-FNA by using a linear-array echoendoscope and 22-gauge needles. RESULTS: Adequate specimens were obtained from 112 lesions. Carcinomas were identified in 68 cases (60.7%), 56 (50%) of pancreatic origin and 12 (10.7%) from distant primary tumors. The metastases were all located in the head and body of the pancreas and measured 1.8 to 4.0 cm. The echo-texture was heterogeneous or hypoechoic in all cases and resembled that of primary tumors. Six of the 12 patients with metastatic disease had a prior diagnosis of cancer (breast, 3; renal cell, 2; salivary gland, 1), 4 of them with a recurrence and 2 with a second carcinoma metastasizing to the pancreas. Six patients without a prior diagnosis of cancer had metastases from renal cell, colonic, ovarian, and esophageal carcinomas; one metastasis was from an unknown primary and another was from a malignant lymphoma. These findings influenced the therapeutic strategy in 8 patients who underwent nonsurgical palliation. There were no complications. CONCLUSIONS: Pancreatic metastasis is an important cause of focal pancreatic lesions, but the EUS features are not diagnostic. Simultaneous EUS-FNA allows cytodiagnosis and can have a decisive influence on the selection of appropriate therapeutic strategies.

EUS-guided fine-needle aspiration cytodiagnosis of hilar cholangiocarcinoma: a case series.

BACKGROUND: Improved methods of tissue diagnosis for obstruction at the hilum of the liver (porta hepatis) have contributed substantially to the preoperative diagnosis of cholangiocarcinoma. Endoscopic brushing during endoscopic retrograde cholangiopancreatography (ERCP), with sensitivity of 20% to 100%, is the preferred technique for obtaining accurate pathologic results. Extensive hepatic resection with curative intent as well as modern approaches to palliative treatment are based on definitive diagnosis. This is a study involving endosonography-guided, fine-needle aspiration (EUS-FNA) for cytodiagnosis of potentially operable hilar cholangiocarcinoma when brush cytology was negative or unavailable. METHODS: Ten consecutive patients (7 men, 3 women; age 47 to 78 years, median 59 years) with bile duct strictures at the hepatic hilum, diagnosed by CT and/or ERCP, underwent EUS-FNA using linear echoendoscopes and 22-gauge needles. RESULTS: Adequate material was obtained in nine patients. Cytology revealed cholangiocarcinoma in seven and hepatocellular carcinoma in one. One benign inflammatory lesion identified on cytology proved to be a false-negative finding by frozen section. Metastatic locoregional hilar lymph nodes were detected in two patients, and in one patient the celiac and para-aortic lymph nodes were aspirated to obtain tissue proof of distant metastasis. There were no complications. CONCLUSIONS: When standard methods of tissue diagnosis are inconclusive, EUS-guided FNA may have a potential role in the diagnosis of primary cholangiocarcinoma of the hepatic hilum. As a new, minimally invasive approach, it proved to be technically feasible without significant risks.

Endosonography-guided, fine-needle aspiration cytology extending the indication for organ-preserving pancreatic surgery.

OBJECTIVE: Organ preserving pancreatic resections are considered whenever malignant disease is ruled out. In tumors of low malignant potential such as cystadenomas and neuroendocrine tumors, the diagnosis is rarely established preoperatively. We studied the feasibility of cytodiagnosis using endosonography-guided fine-needle aspiration in determining the operative approach. METHODS: A total of 78 patients (16 female, 62 male; mean age 61.4 yr, range 31-82 yr) with focal pancreatic lesions underwent EUS-FNA. Final diagnosis was confirmed by histology, cytology, or clinical follow up (>9 months). Patients with tumors of low malignant potential were managed by customized pancreatic resections. RESULTS: Final diagnosis was malignant tumors in 36 patients, tumors of low malignant potential in nine (six, neuroendocrine, two, borderline mucinous cystadenomas, one, borderline adenocarcinoma), and benign in 31 (two inadequate smears). No complications occurred. With six false-negative and no false-positive results, the accuracy, sensitivity, specificity, and positive and negative predictive values were 92%, 84%, 100%, 100%, and 86%, respectively. Five patients with low malignant tumors underwent duodenum-preserving pancreatic head resection, three mid segment resection, and one pylorus-preserving pancreatoduodenectomy. CONCLUSIONS: EUS-FNA is useful in the preoperative cytodiagnosis of pancreatic tumors of low malignant potential. It extends the indication for organ-preserving pancreatic resections and avoids the unnecessary sacrifice of adjacent organs.

Mediastinal lymphadenopathy in patients with or without previous malignancy: EUS-FNA-based differential cytodiagnosis in 153 patients.

OBJECTIVE: Mediastinal lymphadenopathy (ML) is a cause for concern, especially in patients with previous malignancy. The investigation of choice is thoracic CT with a variable sensitivity and specificity requiring tissue diagnosis. We used endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for cytodiagnosis of ML in patients with and without previous malignancy. The cause, distribution of lesions, and incidence of second cancers were investigated. METHODS: Linear echoendoscopes and 22-gauge needles for cytology were used for EUS-FNA. A cytological diagnosis of malignancy was accepted, and histology or consistent follow-up of at least 9 months confirmed benign results. RESULTS: One hundred fifty-three patients underwent EUS-FNA between November 1997 and November 1999 (mean age, 60 yr; range, 13-82 yr; 105 men). Cytology was adequate in 150 patients. Final diagnosis was malignancy in 84 and benign in 66 patients (sensitivity, specificity, and diagnostic accuracy: 92%, 100%, 95%, respectively). In 101 patients without previous cancer cytology identified 48 malignant (lung, 41; extrathoracic, 7) and 51 benign lesions (inflammation, 35; various, 9; sarcoidosis, 7) (sensitivity, specificity, accuracy: 88%, 100%, 94%). Fifty-two patients had prior malignancy, mostly in extrathoracic sites. Cytology revealed recurrences in 21 patients, second cancer in 9 and benign lesions in 21 patients (inflammatory, 11; sarcoidosis, 8; tuberculosis, 1; abscess, 1) (sensitivity, specificity, accuracy: 97%, 100%, 98%). CONCLUSIONS: In patients without previous cancer malignant ML originates from the lung >80%. In those with previous malignancy recurrence of extrathoracic sites is the major cause. Benign lesions and treatable second cancers occur in a significant frequency, emphasizing the need for tissue diagnosis. EUS-FNA is a safe and minimally invasive alternative for cytodiagnosis in the mediastinum.

Endoscopic ultrasonography-guided fine-needle cytodiagnosis of mediastinal metastases from renal cell cancer.

BACKGROUND: Endoscopic ultrasonography (EUS) has become the investigation of choice for the evaluation of the mediastinum. Lung and mediastinum are amongst the common sites of metastases from renal cell cancer (RCC). We diagnosed metastatic RCC in mediastinal lymph nodes by EUS-guided fine-needle aspiration (FNA) cytology. METHODS: A total of 111 patients with mediastinal lymph nodes had undergone EUS-FNA using a linear array echo endoscope and a 170 cm, 22 G GIP needle consecutively. Smears were prepared, air-dried, and sent to an independent cytologist. RESULTS: Seven patients (all males, mean age 64.8 years, range 45-72) were diagnosed cytologically to have metastatic RCC. Three patients had been diagnosed with RCC in the past (2, 7, and 17 years ago) while in the others, this was primarily diagnosed on the basis of EUS-FNA. The EUS features of these mediastinal RCC metastases include irregular lesions with inhomogenous echotexture, measuring 2.8 cm (median; range 1.0-4.5) located predominantly in the posterior mediastinum. CONCLUSION: EUS-FNA diagnosis of metastatic RCC is safe and feasible. It is especially useful in the evaluation of the mediastinum for suspected metastases. Cytology examination results in combination with clinical features could suggest the site of origin of the primary, assisting in further management.

Prospective evaluation of morphology, function, and quality of life after extracorporeal shockwave lithotripsy and endoscopic treatment of chronic calcific pancreatitis.

OBJECTIVE: Therapeutic endoscopy may be effective in selected patients with chronic calcific pancreatitis (CCP). We prospectively evaluated the early outcome of extracorporeal shockwave lithotripsy (ESWL) in combination with interventional endoscopy, using broad inclusion criteria. METHODS: A total of 48 consecutive patients (35 male, 13 female) were recruited for ESWL and endoscopic therapy of symptomatic CCP. Symptoms, quality of life, pancreatic morphology and function were assessed before and after. RESULTS: Multiple stones (n = 43), strictures (n = 34), and pancreas divisum (n = 11) were found. A median of 13 ESWL sessions (range 2-74) with a median of 22,100 shockwaves (1,700-150,900) were required. Endoscopic pancreatic sphincterotomy (n = 48), stricture dilation (n = 12), and/or stenting (n = 27) were performed. After therapy, drainage of the pancreatic duct system was achieved in 36, complete stone clearance in 21 patients. Follow-up (n = 38) at 7 months (range 5-9) showed a significant decrease in pancreatic duct diameter (p < 0.001) and pain score (p < 0.0001) whereas complete pain relief was observed in 45% of cases. Several quality of life scores improved significantly. Weight gain occurred in 68% of patients. Normalization of fasting blood glucose and HbA1c levels were observed in four patients, without modifying their treatment. Improvement in pain score correlated with weight gain and decrease in pancreatic duct diameter. Nonalcoholic etiology was associated with a better chance for improvement in pain score and decrease in pancreatic duct diameter. The presence of strictures did not deteriorate the clinical outcome. CONCLUSIONS: Besides pain relief, ESWL in combination with interventional endoscopy resulted in pancreatic ductal decompression, weight gain, and improvement in quality of life in a considerable number of patients with advanced CCP.

Selective association of lipoprotein cholesteryl esters with liver plasma membranes.

High-density lipoprotein (HDL) cholesteryl esters are taken up by hepatocytes without parallel uptake of HDL apolipoproteins. This selective uptake of HDL cholesteryl esters is mediated by a non-endocytotic mechanism. Recently, selective uptake of cholesteryl esters also from low-density lipoprotein (LDL) was demonstrated. In this study, the role of the plasma membrane in selective uptake by the liver was investigated. Plasma membranes were prepared from rat liver or from human Hep G2 hepatoma cells. Human HDL3 (d = 1.125-1.21 g/ml) was either radioiodinated or labeled with [3H]cholesteryl oleate. Human low-density lipoprotein (d = 1.019-1.05 g/ml) was labeled in its protein and in its lipid moiety as well. Labeled lipoproteins, unlabeled lipoproteins and membranes were incubated. After separation by ultracentrifugation, apparent lipoprotein particle association with membranes was determined. Plasma membranes from rat liver and Hep G2 cells bound 125I-HDL3, indicating specific HDL3 particle binding. With both types of membrane, apparent HDL3 particle association according to [3H]cholesteryl oleate-labeled HDL3 was in significant excess on that due to 125I-HDL3. This indicates selective, i.e., particle binding independent, association of cholesteryl esters with the membrane. Excess unlabeled HDL3 competed for selective association, indicating a specific process. Selective association of HDL3 cholesteryl esters was concentration-, time-, temperature-dependent; however, parameters differed from HDL3 particle binding. HDL3 was modified by nitration; this modification inhibited HDL3 particle binding in contrast to unchanged selective association. These results suggested distinct membrane sites for HDL3 particle binding and selective cholesteryl ester association. Regulation of selective association was investigated. Hep G2 cells were cholesterol-loaded or cholesterol-depleted. Cellular cholesterol-loading down-regulated selective association of HDL3 cholesteryl esters with isolated membranes prepared from these cells. In parallel, selective uptake of HDL3 cholesteryl esters by Hep G2 cells was down-regulated in cholesterol-loaded cells. This parallel regulation of selective association with membranes and selective uptake by cells suggests a functional relationship. LDL, radiolabeled in its protein and in its lipid moiety, was incubated with liver plasma membranes. Besides LDL holo-particle receptor binding, also LDL cholesteryl esters were selectively associated with membranes. These data showed that selective association with membranes is not restricted to HDL but can occur from LDL as well. It is concluded that HDL3 as well as LDL cholesteryl esters can selectively be associated with hepatic plasma membranes, i.e., independent from particle binding. Results suggest an important role of the plasma membrane in the mechanism of selective cholesteryl ester uptake by the liver.

A pool of reversibly cell-associated cholesteryl esters involved in the selective uptake of cholesteryl esters from high-density lipoproteins by Hep G2 hepatoma cells.

Selective uptake of high-density lipoprotein (HDL) cholesteryl esters without parallel uptake of HDL apolipoproteins occurs by a non-endocytotic pathway that results in net delivery of cholesteryl esters to cells. With respect to the cellular mechanism of this pathway, previous studies with adrenal cells showed a cholesteryl ester pool that is reversibly associated with cells and which appears to mediate irreversible selective uptake. A cholesteryl ester pool with similar properties was observed in plasma membranes isolated from adrenal cells, suggesting that this is the site of the cellular pool. Human Hep G2 hepatoma cells also selectively take up HDL cholesteryl esters. Therefore we asked if these cells have a reversibly cell-associated cholesteryl ester pool as well that could mediate irreversible selective uptake. To do this, human HDL3 (d = 1.125-1.21 g/ml) was labeled in both its protein and cholesteryl ester moieties. Uptake of HDL3 tracers by Hep G2 cells was then studied. After an uptake incubation in the presence of labeled HDL3, either cellular uptake of tracers was immediately determined or cells were 'chase' incubated in the presence of unlabeled HDL before determination of cellular tracer content. Hep G2 cells selectively took up HDL3 cholesteryl esters under these conditions. However, a fraction of cholesteryl ester tracer selectively taken up was chased from the cells by subsequent incubation in the presence of unlabeled HDL. This reversible pool of cholesteryl ester tracer was distinct from that irreversibly internalized, and in excess of that accounted for by dissociation of labeled HDL3 particles bound to the cell surface. Selective uptake was down-regulated by prior incubation with LDL, and cholesteryl ester tracer in the reversible pool was down-regulated in parallel. Plasma membranes were isolated from Hep G2 cells and incubated with doubly labeled HDL3. HDL3 particles bound to these membranes, as indicated by the apolipoprotein tracer. However, HDL cholesteryl esters associated with plasma membranes in excess on that accounted for by HDL3 particles. This selective association of HDL3 cholesteryl ester tracer with membranes was reversible, and the tracer was chased during incubation in the presence of unlabeled HDL. These results suggest that, as with steroidogenic cells, a reversible pool of cholesteryl esters localized in the plasma membrane is involved in selective uptake of HDL3 cholesteryl esters by hepatic cells at a step prior to irreversible internalization.

Pharmacological responsiveness of winter depression.

Seasonal affective disorders (SADs) are disturbances of mood bearing a fixed relationship to season. Wintertime depression is the most widely accepted form of SAD. Full-spectrum, bright artificial light is the standard treatment for this syndrome. Tranylcypromine was effective in the treatment of 14 patients meeting both the National Institute of Mental Health and DSM-III-R criteria for winter depression. The average patient experienced a 91 percent reduction in depressive symptoms within 3 to 4 weeks of the initiation of this treatment. Desipramine initially appeared to be an effective treatment for winter depression. Eight patients started treatment with desipramine in October or November. One patient was unresponsive, and 8 patients appeared to be responsive but relapsed in the following 2 to 4 months. Twenty-five patients were subsequently treated with bupropion. One patient was unresponsive to bupropion, but the others experienced a substantial reduction in symptoms. Chronobiologic properties that might explain or predict the effectiveness of drugs used to treat winter depression are discussed.

Regulation of hepatic cholesterol and lipoprotein metabolism in ethinyl estradiol-treated rats.

The regulation of hepatic cholesterol and lipoprotein metabolism was studied in the ethinyl estradiol-treated rat in which low density lipoprotein (LDL) receptors are increased many fold. Cholesterol synthesis was reduced at both its diurnal peak and trough by ethinyl estradiol. The diurnal variation in 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase was abolished, whereas that for acyl coenzyme A: cholesterol acyltransferase (ACAT) was retained. LDL receptor number did not vary diurnally. Feeding these animals a cholesterol-rich diet for 48 h suppressed cholesterol synthesis and reductase activities to levels similar to those found in cholesterol-fed control animals, but ACAT activity was unaffected. LDL receptors were reduced about 50%. Intravenously administered cholesterol-rich lipoproteins suppressed HMG-CoA reductase and LDL receptors in 2 h but had a variable effect on ACAT activity. Intragastric administration of mevalonolactone reduced reductase and increased acyltransferase activity but had little effect on LDL receptors when given 2 or 4 h before death. Although animals fed a cholesterol-rich diet before and during ethinyl estradiol treatment became hypocholesterolemic, free and esterified cholesterol concentrations in liver were high as was ACAT activity. HMG-CoA reductase was inhibited to levels found in control animals fed the cholesterol-rich diet. LDL receptors were increased to a level about 50% of that reached in animals receiving a control diet and ethinyl estradiol. These data demonstrate that key enzymes of hepatic cholesterol metabolism and hepatic LDL receptors respond rapidly to cholesterol in the ethinyl estradiol-treated rat. Furthermore, estradiol increases LDL receptor activity several fold in cholesterol-loaded livers.

Membrane binding sites for plasma lipoproteins on endosomes from rat liver.

Highly purified endosomal membranes from rat liver, enriched in receptors for a number of macromolecules taken up into hepatocytes via the coated pit/endosome/lysosome pathway [including the receptor for low density lipoproteins (LDL)], were used to characterize binding sites for lipoproteins containing apolipoprotein E. In endosomal membranes from livers of estradiol-treated rats, in which LDL receptors are induced manyfold, two high-affinity binding sites were found for two apolipoprotein E-rich lipoproteins: very low density beta-lipoproteins (beta-VLDL) from cholesterol-fed rabbits and rat chylomicron remnants. One of these sites, binding to which is inhibited by 30 mM EDTA, appears identical to the LDL receptor by ligand and immunoblotting and other characteristics. The other site, highly resistant to EDTA, does not bind LDL. Binding to the EDTA-resistant site, however, is readily inhibited by heparin (as is the LDL receptor) and also by antisera prepared against rat or bovine LDL receptor. The distribution of the EDTA-resistant site among early endosomes, late endosomes, and endosome-derived receptor-recycling membranes is similar to that of the LDL receptor and other recycling receptors. The LDL receptor was present in endosomal membranes from livers of untreated rats at about 10% of the level found in membranes from estradiol-treated rats, but the EDTA-resistant site was barely detectable. No saturable binding of beta-VLDL that could not be inhibited by antisera to the LDL receptor could be detected in endosomal membranes from livers of either untreated or estradiol-treated rats. The EDTA-resistant site may be a modified form of the LDL receptor that recognizes apolipoprotein E but not the B apolipoprotein of LDL. Alternatively, it may be a distinct receptor sharing immunological determinants with the LDL receptor, specialized for the endocytosis of certain lipoproteins containing apolipoprotein E, including chylomicron remnants.

Isolation and characterization of three endosomal fractions from the liver of estradiol-treated rats.

Three distinct endosomal fractions were isolated in high purity from livers of estradiol-treated rats. Each fraction had characteristic physical and ultrastructural properties, but the lipid composition and major proteins of their membranes were similar and differed from those derived from the Golgi apparatus. Injected radioiodinated low density lipoproteins accumulated first in the fraction of intermediate density and later in the low density fraction. The latter was composed almost exclusively of lipoprotein-filled multivesicular bodies, most of which had a single membranous appendage. The fraction of intermediate density was composed of lipoprotein-filled vesicles that were smaller than multivesicular bodies and also had membranous appendages. The high density fraction was composed of membranes resembling the appendages of the two vesicular fractions. All three fractions were enriched in receptors for low density lipoproteins and asialoglycoproteins, but receptor concentrations were considerably reduced in multivesicular bodies. The fraction of intermediate density may represent the compartment of uncoupling of receptor and ligand (CURL) described by Geuze et al. [Geuze, H. J., Slot, J. W., Strous, G. J. A. M., Lodish, H. F. & Schwartz, A. L. (1983) Cell 32, 277-287]. CURL vesicles may lose some of their appendage as multivesicular bodies are formed. The high density fraction then may represent a receptor-recycling compartment.