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C Hoang

Publications and source records attributed to C Hoang.

At least 37 records · Page 2Linked to original sources
PubMed1994

[Flow cytometry of thyroid tumors. Study of fresh tissue in 50 patients].

OBJECTIVES: A measurement of cell DNA content would be highly useful in determining the malignant nature of thyroid tumours in cases without distinctive features such as metastases, capsule invasion or emboli. Abnormal cell ploidy can be recognized with flow cytometry, but it is not known whether such results have diagnostic value. We therefore compared--in a double blind prospective study--the results of flow cytometry and pathologic diagnosis in fresh tumoural and non-tumoural thyroid cells. METHODS: Fifty unselected cold thyroid nodules were obtained from 50 consecutive patients (40 women, 10 men; age 18-80 years; mean 46) who underwent surgery within a 6 month period. Surrounding non-tumoural tissue was also obtained in 46 of them. Cell ploidy and the percentage of cells in each cell phase was determined with flow cytometry for both tumoural and nontumoural tissues. Two pathologists, unaware of the flow cytometric results, independently established the histologic diagnosis according to the WHO classification. RESULTS: The pathologic diagnosis was carcinoma in 7 cases (papillary carcinoma 6, vesicular carcinoma 1) and benign adenomas in 43 (29 macrovesicular, 11 microvesicular, 3 oncocytal). All the non-tumoural tissue samples were diploid. All 7 carcinomas were diploid and 10 of the 43 benign adenomas were aneuploid (4 near-diploid, 3 hyperploid, 1 near-tetraploid, 2 multiploid). The mean proliferation index was increased in 5 diploid tumours. CONCLUSION: These findings confirm that cell ploidy measured by flow cytometry is of no diagnostic value in the thyroid gland. It was also revealed that aneuploidy in adenomas may be related to tissue rearrangements of undetermined prognostic significance.

Adenoma↗
PubMed1994

Association of lipid accumulation in small intestinal mucosa with decreased serum triglyceride and cholesterol levels in AIDS.

Lipid accumulation has been described in the duodenal lamina propria of human immunodeficiency virus (HIV)-infected patients with diarrhea and malabsorption. Using light and electron microscopy, we studied duodenal biopsies obtained from 54 consecutive HIV-infected patients by means of upper gastrointestinal endoscopy after an overnight fast. The presence of diarrhea and weight loss were recorded, and all the patients had standard stool study for ova, parasites, and bacteria. Serum levels of albumin, triglycerides, and cholesterol were obtained within one week of the endoscopy. Fecal fat and fecal alpha 1-antitrypsin clearance were measured in 11 patients. Lipid accumulation was observed in nine patients (16.6%). Fat droplets were seen in enterocytes, in their basolateral membrane spaces, and in the lamina propria. The mean serum levels of triglycerides (1.85 +/- 0.20 mmol/liter) and cholesterol (2.81 +/- 0.30 mmol/liter) were significantly lower in the patients with enteric steatosis than in patients without this anomaly (respectively, 3.38 +/- 0.39 and 3.97 +/- 0.18 mmol/liter, P < 0.001 P < 0.01). The mean amount of fecal fat in the three patients with lipid accumulation (16 +/- 1.60 g/24 hr) was significantly larger than in the eight patients without lipid accumulation (4.50 +/- 0.62 g/24 hr, P < 0.01). These findings suggest that fat malabsorption in HIV-infected individuals is due to a blockage of transport through the duodenal mucosa. The frequency of diarrhea, weight loss, or identified enteric pathogens did not differ significantly between patients with and without enteric steatosis. Both the etiology and the pathophysiology of these alterations remain to be documented.

Acquired Immunodeficiency Syndrome↗
PubMed1994

The diagnostic value of fine-needle aspiration biopsy under ultrasonography in nonfunctional thyroid nodules: a prospective study comparing cytologic and histologic findings.

Fine-needle aspiration biopsy (FNAB) of thyroid nodules has been proposed as a preoperative screening method to reduce the number of patients with benign nodules referred for surgery. Only a few previously published studies have compared cytologic results with a systematic surgical control; furthermore, the role of ultrasound guidance for FNAB in obtaining representative material has been poorly evaluated. The authors tried to assess the diagnostic value of FNAB performed under ultrasonography in a series of patients with a cold nodule and a systematic surgical control. This prospective study included 132 consecutive patients, 19 men and 113 women, aged from 18 to 82 years. The rate of carcinomas was 13.8%. A very high rate of adequate material was obtained (96.2%). Sensitivity, specificity, and global accuracy were 95%, 87.7%, and 89%, respectively. These results, which are equivalent to those previously published but associated with a low level of insufficient material, emphasize the diagnostic value of thyroid FNAB.

Adult↗
PubMed1994

Cryoglobulinemia in chronic liver diseases: role of hepatitis C virus and liver damage.

BACKGROUND/AIMS: Mixed cryoglobulinemia is frequently associated with liver diseases. The respective role of hepatitis C virus (HCV) and liver damage in the pathogenesis of cryoglobulinemia is investigated in this study. METHODS: The prevalence of cryoglobulinemia in 226 consecutive patients with chronic liver diseases (hepatitis C, 127; hepatitis B, 40; other diseases, 59) was studied, and the epidemiological, biological, histological, and virological features in these three groups were analyzed. Anti-HCV antibodies, HCV proteins, and HCV RNA were searched in the cryoprecipitates. RESULTS: The prevalence of mixed cryoglobulinemia was high (41.5%) in patients with liver diseases and higher in patients with hepatitis C (54.3%) than in patients with hepatitis B (15%) or other causes of liver disease (32%). Patients with cryoglobulinemia had cirrhosis more frequently and had a longer history of hepatitis. In patients with hepatitis C, HCV RNA sequences and HCV proteins were detected in the cryoprecipitate. Cryoglobulins became undetectable in 21 of 43 patients treated with interferon. CONCLUSIONS: These findings suggest that HCV is a major cause of cryoglobulinemia. Besides viral infection itself, multiple factors appear to be responsible for the production of cryoglobulins, including cirrhosis and duration of liver disease.

Adult↗
PubMed1994

[Cholestatic viral hepatitis A in adults. Clinical, biological and histopathological study of 9 cases].

OBJECTIVES: We report here 9 cases of acute viral hepatitis A leading to hospitalization between June 1989 and October 1992. The main feature was a marked and protracted cholestasis. RESULTS: Jaundice lasted an average of 77 +/- 39 days (range: 30-120) and total serum bilirubin concentrations were 265 +/- 184 mumol/L (range: 51-560). IgM anti-HAV was present in the serum for 6.3 +/- 5.5 months (median: 4, range: 2-19). Histopathological examination of the liver was performed in 6 patients and most showed intralobular cholestasis and portal tract inflammation associated with dystrophy and paucity of bile ducts. Acute renal failure was noted in one patient. In three patients, whose pruritus was not relieved by cholestyramine, plasma exchange was an effective therapy. CONCLUSION: These case reports confirm the severity of viral hepatitis A in adults and emphasize the importance of vaccination.

Acute Kidney Injury↗
PubMed1994

[Appendiceal localization of bilharziasis: value of extemporaneous histological examination].

The association of appendicitis with schistosomiasis in the appendix is extremely rare in France. We report herein a new case in which the diagnosis was made, in the presence of pseudo-tumoral appendicitis, by frozen section biopsies. The patient presented with a typical acute appendicitis, without urinary symptoms, and with granulocytosis (14000 white cells/mm3, without eosinophilia). At laparotomy, the appendix was voluminous, with necrotic abscess, and lymph node masses were noted on the greater omentum. Frozen section biopsies of an omental tumor showed schistosoma eggs, without malignant cells. Appendicectomy and partial omentectomy were performed. Postoperative course was uneventful. Pathologic examination of the resected specimen showed schistosoma eggs in all layers of the appendix, and in the omentum. Final diagnosis was established by positive serology and by findings Schistosoma haematobium eggs in the urine. The patient was treated postoperatively by praziquantel. In conclusion, in case of acute appendicitis, with pseudotumorous appendix and lymph node masses, even with poor epidemiological findings on the clinical history, frozen section biopsies can sometimes establish the diagnosis of schistosomiasis with appendicitis, and avoid unjustified bowel resection.

Adult↗
PubMed1993

AIDS-related cholangiopathy. Critical analysis of a prospective series of 26 patients.

Several types of biliary tract abnormality of undetermined origin have been described among AIDS patients. The aims of this study are: (1) to evaluate whether biliary tree involvement is in fact one or several homogeneous morphological entities, (2) to specify the role of CMV or Cryptosporidium sp. infection, and (3) to evaluate the possible efficacy of treatment. Since ultrasound had revealed abnormality in the biliary tree, 26 consecutive AIDS patients underwent cholangiography. Cholangiograms enabled us to distinguish between two types of biliary tract involvement: (1) gradual and regular stenosis of the terminal portion of the common bile duct associated with dilation but without irregularity of the intrahepatic biliary ducts was present in 27% of our cases, and (2) distal stenosis of the extrahepatic biliary ducts combined with diffuse irregularity of the caliber of the intrahepatic bile ducts was present in 73% of our cases. Concomitant infection by CMV or Cryptosporidium sp. was significantly more frequent when intrahepatic duct irregularities were present (94%) than when absent (14%, P < 0.001). Anti-CMV treatment and sphincterotomy were unsuccessful in treating anomalies of the intrahepatic biliary tract. Conversely, sphincterotomy caused rapid and lasting disappearance of pain in all our patients. In conclusion, biliary tract involvement in AIDS patients is of two types. CMV infection and infection by Cryptosporidium sp. are most frequent when the large intrahepatic ducts are implicated.

AIDS-Related Opportunistic Infections↗
PubMed1993

Relationship of apical lymph node involvement to survival in resected colon carcinoma.

In a prospective study of 197 patients with resected colon carcinoma treated between 1974 and 1985, we explored the relationships between pathologic parameters, and the effect of the latter on survival, to identify the parameter whose systematic measurement would improve the predictive capacity of pathologic staging. Prognostic characteristics were studied by univariate analysis. The results showed significant relationships between the location and number of lymph nodes involved, blood vessel invasion, depth of tumor penetration, and metastases. The five-year survival rates were 45 percent and 17 percent (P < 0.001) for patients without and with apical lymph node involvement, respectively, and 44 percent and 6 percent (P < 0.05) for those with four or less nodes involved and more than four involved, respectively. Among the patients treated by incomplete resection, the respective survival rates of those resected for metastases and of those resected for apical lymph node involvement did not differ significantly. We conclude that the involvement of apical lymph nodes has a significant effect on prognosis and suggest systematic pathologic examination of these nodes to allow simpler and more reproducible selection of patients for treatment by incomplete resection who are at high risk of disease-related death.

Adenocarcinoma↗
PubMed1993

[Cystic lymphangioma of the duodenum revealed by digestive hemorrhage and associated with exudative enteropathy].

Cystic lymphangioma is a rare and benign congenital lesion of the lymphatic system, which can become manifest at any age. Intra-abdominal cysts are found in less than 10% of cases and mesenteric involvement is the most common. The case of a patient with intra-abdominal cystic lymphangioma that involved the liver, the spleen, the kidney and the small intestine, and complicated by gastrointestinal bleeding and protein losing enteropathy is reported herein. Despite severe gastro-intestinal manifestations, spontaneous outcome was favorable. This observation suggests that a) duodenal cystic lymphangioma must be considered as a cause of gastrointestinal bleeding and of protein losing enteropathy, b) conservative treatment can be proposed.

Aged↗
PubMed1993

Immunohistochemical detection of cell proliferation in gastric carcinomas with the monoclonal antibody Ki-67. A study of 24 cases.

The proliferative activity in 24 gastric carcinomas was determined by an immunohistochemical method using monoclonal antibody Ki-67 (ABC method). Immunostained nuclei were counted by two observers through a Nachet NS 1000 image numeriser. Three grades were defined according to stained nuclei percentage (proliferation index Pi = percentage of cells engaged in cellular cycle outside Go): grade 1 (Pi < 20%); grade 2 (20% < Pi < 40%); grade 3 (Pi > 40%). About 60% of tumours were in grade 1 and 10% in grade 3. No correlations were observed between Pi and the following parameters: histological differentiation; parietal extension; presence or absence of metastasis. These results may be compared to the two other available studies of Ki-67 antibody in gastric cancers. Our study also showed a heterogeneous distribution of immunostained nuclei, within each single tumour and from one tumour to another, which has been noted in one previous study and in a similar one we made on colorectal carcinoma. This heterogeneity is the consequence of the variability of carcinomatous cell proliferative activity; an important biological factor in the evaluation of tumoral process. The proliferative activity in gastric carcinomas provides an estimation of tumour dynamics that might be a prospective criterium for tumoral process evaluation.

Antibodies, Monoclonal↗
PubMed1992

[Histopathology and ultrastructure of opportunistic infections of the digestive tract in acquired immunodeficiency syndrome].

Light and electron microscopy studies of digestive tract biopsy specimens from AIDS patients are very useful for the detection of opportunistic pathogens which may be located in: the lumen (bacteria, Candida albicans, Giardia lamblia), enterocyte brush border (Cryptosporidium sp), enterocyte cytoplasm (Enterocytozoon bieneusi), enterocyte nuclei (cytomegalovirus), or cytoplasm of lamina propria macrophages (Mycobacterium avium intracellulare). These studies may also be useful to detect combinations of morbid conditions and to evaluate the effectiveness (if any) of therapeutic agents.

AIDS-Related Opportunistic Infections↗