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K J Lewin

Publications and source records attributed to K J Lewin.

At least 55 records · Page 3Linked to original sources
PubMed1992

Distribution of dysplasias and early invasive carcinoma in Barrett's esophagus.

To assess the anatomic relationships between areas of dysplasia and "early" carcinoma, we evaluated histologically the entire mucosal surfaces of seven esophagectomy specimens resected for high-grade dysplasia or early invasive (intramucosal and submucosal) carcinoma. We developed surface area maps and assessed the various degrees of dysplasia or carcinoma at 10 equidistant points. Our analysis shows an equal likelihood of high-grade dysplasia and/or early invasive carcinoma occurring throughout the length of Barrett's epithelium. Foci of carcinoma appear within fields of Barrett's epithelium and adjacent to areas of dysplasia, supporting a dysplasia-carcinoma sequence. The amount of dysplastic epithelium appears related to the surface area of Barrett's epithelium present. However, we found no association between the extent of dysplasia and the likelihood of finding carcinoma. This study supports the current standard of practice for clinical surveillance of patients with Barrett's esophagus by uniformly distributed endoscopic biopsy of the complete length. In addition, the presence of any degree of dysplasia may be an indication for close clinical follow-up.

Aged↗
PubMed1992

Basal cell hyperplasia of prostate: an elusive lesion?

We report a case of basal cell hyperplasia of the prostate accompanying benign prostatic hypertrophy. The histogenesis of the basal cells as well as the histologic features and differential diagnosis of basal cell hyperplasia are reviewed.

Humans↗
PubMed1992

Malignant and premalignant lesions of the esophagus.

Squamous cell carcinoma is the most common malignant tumor of the esophagus and it is one of the most common fatal cancers worldwide. There is great geographic variation in occurrence of these tumors. Especially high-risk areas have been identified in Northern Iran, Central Asian Republics, Northern China and South Africa. In some of these areas annual mortality rates reach 133/100,000 and over 20% of the population dies of esophageal cancer. The mortality in the US is considerably lower (3 to 8 per 100,000). In common with squamous dysplasias elsewhere eg the cervix, squamous dysplasia of the esophagus also appears to be a precancerous lesion. We have found that squamous dysplasia and early cancer are characterized by a number of distinctive endoscopic changes, namely, mucosal friability, erosions, plaques and nodules. Another finding of interest is the failure on our part to confirm the frequency of esophagitis in high risk areas. Barrett's esophagus is an epithelial metaplasia which replaces esophageal squamous epithelium for variable lengths from the lower esophageal sphincter region cephalad. It is a complication that occurs in approximately 12% of patients with prolonged gastroesophageal reflux. The importance of this disorder is that it is associated with an increased risk of adenocarcinoma of the esophagus. In assessing biopsies from patients with Barrett's esophagus, the main role of the pathologist is to be on the alert for histologic features of dysplasia and adenocarcinoma. Since dysplasia in Barrett's is endoscopically invisible, multiple biopsies are necessary if surveillance is to be successful in detecting dysplastic lesions and early carcinoma.(ABSTRACT TRUNCATED AT 250 WORDS)

Esophageal Neoplasms↗
PubMed1991

Immunohistochemical estrogen receptor assessment in hyperplastic, neoplastic, and physiologic endometria.

Endometrial hyperplasias and some endometrial carcinomas arise in a setting of estrogen excess. Steroid hormones interact with cells via specific receptors; assessing receptor levels may indicate a tissue's potential for interaction with that hormone. To examine estrogen receptor (ER) levels in endometrial hyperplasia, endometrial carcinoma, and physiologically cycling endometrium, an immunohistochemical technique utilizing a monoclonal anti-estrophilin (estrogen receptor) antibody was applied to formalin-fixed, paraffin-embedded tissue. In complex hyperplasia and grade I adenocarcinoma, the mean percentages of epithelial cells demonstrating nuclear staining for ER was mildly decreased compared to proliferative endometrium. A trend was noted toward less ER staining in atypical hyperplasia compared to non-atypical complex hyperplasia. ER varied with physiologic cycling of the endometrium. ER was also present in atrophic endometrium, myometrium, adenomyosis, and leiomyomata. Immunohistochemistry permits localization of ER and is a useful technique in ER assessment of endometrial hyperplasias and carcinomas.

Adenocarcinoma↗
PubMed1991

Rapid diagnosis of Legionella infection by a nonisotopic in situ hybridization method.

The authors report a nonradioactive adaptation of DNA hybridization technology for the direct detection of Legionella organisms in situ in routinely processed histologic specimens. The probe used consisted of synthetic oligodeoxynucleotides, complementary to the ribosomal RNA of all clinically relevant Legionella species, labeled with biotinylated dUTP at their 3' ends. By in situ DNA hybridization and detection with an avidin-alkaline phosphatase complex. Legionella was visualized by light microscopy within the alveoli of lung specimens in 9 of 13 direct fluorescent antibody- or culture-positive cases of Legionnaires' disease. No cross-hybridization was observed in lung specimens infected with Pseudomonas aeruginosa, Klebsiella pneumoniae, Streptococcus pneumoniae, or other pathogens. The authors' results illustrate a novel adaptation of in situ DNA hybridization techniques, usually used for viruses, to the detection of a bacterial organism. The method enables direct visualization of bacterial nucleic acid in infected tissues and may facilitate early diagnosis and treatment of legionellosis.

Adult↗
PubMed1991

Histopathology of bacillary angiomatosis of lymph node.

Bacillary angiomatosis, a recently characterized pseudoneoplastic vascular proliferation caused by a bacterium identical or related to the cat-scratch disease bacillus, usually presents as cutaneous lesions. We report the histologic findings of this disease involving the lymph nodes of two immunocompromised patients. The lymph nodes showed patchy involvement by coalescent nodules of proliferated blood vessels lined by plump endothelial cells with pale cytoplasm. There were foci exhibiting mild to moderate nuclear atypia. Although neutrophil infiltration was prominent in one case, it was minimal in the other. The interstitium was formed by pink-staining material in hematoxylin-eosin-stained sections, and this proved to be aggregated bacilli on Warthin-Starry stain. Recognition of this potentially fatal disease is important because it is curable with antibiotics.

Adult↗
PubMed1991

Diffuse hepatocyte ballooning in liver biopsies from orthotopic liver transplant patients.

Mild to moderate liver injury to the orthotopically transplanted liver may result from acute rejection, mild ischaemia, or viral hepatitis. Because these conditions are often clinically indistinguishable, liver biopsy is frequently helpful. We previously characterized and reported the morphological spectrum of mild-to-moderate ischaemic injury from 170 liver biopsies (51 liver transplant patients). During this review, we found eight patients with a diffuse hepatocyte ballooning pattern. This pattern had some similarity to 'preservation injury' described by others, and in fact seven of the eight patients had these changes within the first 2 weeks post-transplant. However, two of the seven patients also displayed these changes up to 6 months post-transplant and the eighth patient developed these histological patterns only after the early post-transplant period. Follow-up data on patients with diffuse hepatocyte ballooning showed that some reverted to normal histology, some transformed to well-delineated perivenular ballooning, and some progressed to perivenular necrosis and/or infarction. Only when superimposed perivenular necrosis became apparent did the injury become irreversible, necessitating allograft removal or resulting in death. The pathogenesis of diffuse hepatocyte ballooning is unclear. However, the association of some of the cases with 'preservation injury' pattern in the early post-transplant period and the progression of others to necrosis and infarction, suggest an ischaemic basis for this lesion.

Autopsy↗
PubMed1990

Disease recurrence following liver transplantation.

Recurrence of disease following liver transplantation is emerging as a major area of concern. We retrospectively investigated for evidence of recurrent hepatitis B, hepatitis non-A, non-B (NANB), primary biliary cirrhosis (PBC) and malignancy in 106 transplant patients. Recurrence of hepatitis B was diagnosed in 11 of 14 (79%) patients who survived longer than 2 months posttransplant. The first histologic evidence of recurrence occurred at 4 to 64 weeks posttransplant (mean, 22.2 weeks). In two patients, progression to cirrhosis was documented histologically. Recurrence was diagnosed in three patients transplanted for fulminant hepatic necrosis due to hepatitis B. Administration of hepatitis B vaccine and hepatitis B immunoglobulin was ineffective in preventing recurrence. Recurrence of hepatitis NANB was diagnosed in only two of 23 patients transplanted for hepatitis NANB cirrhosis. Evidence of posttransplant hepatitis was also detected in one of 10 patients transplanted for fulminant hepatitic failure presumably caused by hepatitis NANB. Recurrence of PBC was not diagnosed in any of 15 patients, but the length of follow-up was too limited in most patients to allow definite conclusions to be made. Posttransplant antimitochondrial antibodies titers remained elevated in nine of 11 patients tested. Six of 13 patients transplanted for hepatocellular carcinoma (46%) developed recurrent tumor, and five died. The role of preoperative and postoperative chemotherapy is currently undefined.

Adolescent↗
PubMed1990

Enteric infections.

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Bacterial Infections↗
PubMed1989

Intrahepatic biliary cysts in congenital biliary atresia.

A case of pronounced cystic dilatation of the intrahepatic bile ducts with biliary atresia is presented. Intrahepatic biliary cysts have been described in biliary atresia, although, as far as we are aware, none as extensive as in this case. The cysts represent end-stage obstruction with irreversible liver injury; thus, drainage of these cysts does not alleviate the condition. The differential diagnosis includes Caroli's disease, congenital hepatic fibrosis, and polycystic liver disease.

Biliary Atresia↗
PubMed1989

Cystadenoma of the gallbladder.

A case of obstructive jaundice due to extrinsic common bile duct (CBD) pressure from a gallbladder mass is presented. Endoscopic retrograde cholangiopancreatography (ERCP) demonstrated a dilated CBD and a massively dilated gallbladder. Computed tomography scan of the abdomen revealed a multiseptated cystic structure originating from the gallbladder fossa. Histologic sections of the surgical specimen demonstrated a multilocular cyst lined with biliary-type epithelium. Fibromuscular proliferation of the cyst walls also was noted. A literature search did not reveal documentation of a similar gallbladder lesion. We believe this lesion represents the first reported case of gallbladder cystadenoma.

Aged↗
PubMed1988

Endoscopic biopsy can detect high-grade dysplasia or early adenocarcinoma in Barrett's esophagus without grossly recognizable neoplastic lesions.

There is uncertainty regarding the value of endoscopic biopsy surveillance in Barrett's esophagus because, in retrospective studies, some patients with high-grade dysplasia in endoscopic biopsy specimens have had unexpected advanced adenocarcinoma discovered at the time of esophageal resection. We compared the accuracy of preoperative endoscopic biopsy diagnoses with the final pathologic diagnoses in esophagectomy specimens in 4 patients who had both high-grade dysplasia and intramucosal carcinoma and 4 other patients who had only high-grade dysplasia preoperatively. The histologic lesions in all 8 patients were documented in intact mucosa with no gross evidence of neoplasia by endoscopy. The preoperative diagnoses were defined with an endoscopic biopsy protocol in which specimens were taken with large-channel biopsy forceps at least every 2 cm throughout the length of Barrett's epithelium. Final pathologic diagnoses derived from detailed analysis of the resected specimens confirmed high-grade dysplasia without carcinoma in 4 patients and intramucosal carcinoma in 2 patients. The remaining 2 patients with a preoperative diagnosis of intramucosal carcinoma had focal submucosal invasion by carcinoma in the resected specimens, but no involvement of the muscularis propria or adventitial lymph nodes. Because the natural history of high-grade dysplasia is not known, the decision to operate on patients with this lesion must be carefully weighed and individualized for each patient. Two of our patients who underwent esophageal resection for high-grade dysplasia without cancer died, one immediately postoperatively and the other 9 mo later after a postoperative stroke. Once intramucosal carcinoma is documented, surgery should be considered if the patient is an acceptable operative risk. We conclude that systematic preoperative endoscopic biopsy of intact mucosa in Barrett's esophagus can correctly detect high-grade dysplasia, either alone or in combination with early, treatable adenocarcinoma.

Adenocarcinoma↗
PubMed1988

Detection of cytomegalovirus DNA in classic and epidemic Kaposi's sarcoma by in situ hybridization.

Several lines of evidence have suggested an etiologic association of cytomegalovirus (CMV) with Kaposi's sarcoma. This contention is supported by a pathoepidemiologic survey of 54 cases of acquired immunodeficiency syndrome (AIDS) at our own institution. Of the 27 patients with documented Kaposi's sarcoma, 24 (89%) showed histologic evidence of CMV infection (cytomegalic cells with viral inclusions), whereas only 9 (33%) of the patients with AIDS without Kaposi's sarcoma showed hallmarks of CMV infection. In an attempt to address this question further, we have searched for the presence of CMV nucleic acid sequences in a series of 25 patients with AIDS and Kaposi's sarcoma, using the technique of in situ DNA hybridization. The reliability of the in situ technique is demonstrated, and the technique is shown to be more sensitive than the detection of viral inclusions within Kaposi's sarcoma lesions by routine light microscopy. However, only 20% of our cases showed evidence of CMV involvement, and the CMV-positive cells within the affected Kaposi's sarcoma lesions were few and sparsely distributed. In addition, a companion series of 6 elderly patients with "classic" Kaposi's sarcoma showed no evidence of CMV infection by either conventional microscopy or in situ hybridization. These results do not support the notion of a strong association between Kaposi's sarcoma and CMV, unless the CMV sequences are present at a copy number too low for detection by these methods. The implications of these findings in light of current theories of CMV oncogenesis are discussed.

Acquired Immunodeficiency Syndrome↗
PubMed1988

The role of liver biopsy in evaluating acute allograft dysfunction following liver transplantation: a clinical histologic correlation of 34 liver transplants.

One hundred six liver biopsy specimens from 34 orthotopic liver transplant (OLT) patients were examined and the histologic findings correlated with the clinical course of the patients to determine if specific morphologic patterns were associated with specific causes of acute allograft dysfunction. The principle causes of allograft injury in these patients appeared to be acute rejection and ischemic injury, with rarer cases of viral infection and biliary obstruction. Graft rejection causing transient liver dysfunction was associated with a mixed inflammatory infiltrate in the portal tracts and involving the interlobular bile ducts. Rejection resulting in severe, persistent dysfunction was associated with destruction and loss of the interlobular bile ducts or portal inflammation, followed by acute centrilobular hepatocyte necrosis. Ischemic liver injury was characterized by hepatocyte ballooning and/or hepatocyte necrosis. Ischemic injury causing transient graft dysfunction demonstrated focal, limited areas of hepatocyte necrosis or transient centrilobular hepatocyte ballooning. Severe ischemic injury resulting in persistent dysfunction caused diffuse hepatocyte necrosis or centrilobular ballooning followed by centrilobular hepatocyte loss and severe cholestasis with evidence of bile duct epithelial injury. The histologic patterns observed were not pathognomonic; radiologic studies, bile cultures, and other laboratory tests were necessary to rule out biliary or vascular obstruction and bacterial cholangitis. However, liver biopsies, especially serial biopsies, were helpful in suggesting the probable cause of liver dysfunction and in predicting subsequent allograft recovery or failure.

Adolescent↗
PubMed1988

Massive hepatomegaly in adult polycystic liver disease.

In adult polycystic liver disease, the liver gradually enlarges as it is replaced by cysts. The disease rarely produces symptoms or complications. Liver cysts are thought to arise from aberrant embryonic intrahepatic bile ducts (Von Meyenburg's complexes). We present a case of adult polycystic liver disease with Von Meyenburg's complexes and unusually severe hepatomegaly (7.7 kg, 22,080 cm3). The autopsy prevalence of adult polycystic liver disease at UCLA Medical Center is 0.13%; 93% of these cases had polycystic kidney disease. Adult polycystic kidney disease had associated liver cysts in 45% of cases.

Cysts↗