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J Lauweryns

Publications and source records attributed to J Lauweryns.

At least 19 recordsLinked to original sources
PubMed1996

Malignant myoepithelioma of the breast. Case report with immunohistochemical study.

Malignant myoepitheliomas of the breast are rare. We report a case of spindle cell malignant myoepithelioma studied by light microscopy and immunohistochemistry. The malignant myoepithelial cells stained positively for cytokeratins, smooth muscle actin and vimentin, but not for epithelial membrane antigen. The tumor showed a focal positivity for S100 protein. A short review of the morphology and immunohistochemistry of cases reported in the international literature is given in a table. Morphologically malignant myoepitheliomas can be subdivided into spindle cell malignant myoepitheliomas and malignant adenomyoepitheliomas.

Breast Neoplasms↗
PubMed1995

Papillary cystadenoma of the epididymis: a case report.

In this report a case of bilateral papillary cystadenoma of the epididymis is described, a tumor associated with the Von Hippel-Lindau's disease (cerebelloretinal hemangioblastomatosis). Reports about the Von Hippel-Lindau's disease do only infrequently mention epididymal adenomas because the latter is mostly not associated with any symptoms. Retinal angiomatosis, cerebellar hemagioblastoma, pheochromocytoma and renal cell carcinoma are the lesions in the Von Hippel-Lindau's disease which cause symptoms and as a consequence disease. Because of some histological similarities between papillary cystadenoma and the clear cell type of renal adenocarcinoma a metastasis of a renal cell carcinoma has to be added to the list of differential diagnosis in case of an epididymal benign tumor apart from adenomatoid tumor, fibroma, lipoma,... The epididymal papillary cystadenoma, which is the only known benign epididymal tumor of epithelial origin, is considered a hereditary hamartoma. The precise histogenetic origin is still controversial.

Adult↗
PubMed1994

Intractable asphyxia at birth: analysis of the underlying conditions.

A review of clinical and pathological data on 10,000 consecutive deliveries revealed that the incidence of unexpected and intractable asphyxia at birth despite adequate resuscitation was 0.24%. Lung hypoplasia appeared to be the underlying non-viable condition in 22 out of 24 infants. Attention is drawn to congenital neuromuscular disorders which were found to be the cause of lung hypoplasia in at least 4 out of 22 infants. Some helpful hints for diagnosis are given which may contribute to the final decision making.

Asphyxia Neonatorum↗
PubMed1994

Exophytic papillary prostatic duct adenocarcinoma with endometrioid features, occurring in prostatic urethra after TURP.

We present an eighty-three-year-old man with an exophytic lesion in the prostatic cavity, diagnosed three years after transurethral resection of the prostate, and extending into the bladder. Histopathologically, the tumor was recognized as a papillary ductal adenocarcinoma (primary duct type) with endometrioid features, probably associated with prostatic adenomatous polyp. Acinic adenocarcinoma was absent. The lesion was treated by deep transurethral resection with objective follow-up results after six months. Review of the literature concerning history, embryology, possible pathogenesis, differential diagnosis, and treatment options is included.

Aged↗
PubMed1994

Immunohistochemical localization of prostate-specific markers within the accessory male sex glands of Cowper, Littre, and Morgagni.

OBJECTIVES: The aim of the study was to explore possible production of prostate-specific markers by the embryologically and physiologically related accessory male sex glands, other than the prostate. METHODS: The accessory male sex glands of Cowper, Littre, and Morgagni were studied systematically in 10 whole-mount autopsy and 5 surgical cystoprostatourethrectomy specimens. Immunohistochemistry was applied with the avidin-biotin-peroxidase method and commercially available monoclonal antibodies raised against prostate-specific antigen (PSA) and prostate-specific acid phosphatase (PSAP). RESULTS: All specimens showed clear microscopic identification of these glands except for Cowper's glands, which were not found in most of the surgical cystoprostatourethrectomy specimens but were found coincidentally in one. Localization of the prostate-specific markers PSA and PSAP was demonstrated for the first time in three Cowper's glands, but they were a consistent finding in Littre's and Morgagni's glands when immunohistochemical identification was performed in a systematic fashion. CONCLUSIONS: PSA and PSAP are mostly produced by prostatic tissue, but not exclusively. These findings may have an impact on the specificity and sensitivity of PSA serum levels after radical prostatectomy because they support the hypothesis of extraprostatic sources of PSA.

Acid Phosphatase↗
PubMed1994

Mucin-secreting adenocarcinoma of the prostate with neuroendocrine differentiation and Paneth-like cells.

We present an unusual variant of prostatic adenocarcinoma with obvious mucinous and neuroendocrine features, arising in the transition zone. The neuroendocrine component is largely represented by Paneth-like cells (PLCs). These cells correspond to previously described eosinophilic cells and are amphicrine. We could demonstrate immunohistochemically the presence of calcitonin in some of these PLCs. The prognostic significance of these special characteristics is not well known, but it is most likely that this type of prostate cancer will not respond well to hormonal therapy.

Adenocarcinoma, Mucinous↗
PubMed1994

Florid basal cell hyperplasia of the prostate.

Florid basal cell hyperplasia of the prostate is an uncommon proliferative condition, most often associated with adenomatous hyperplasia. It is considered a benign lesion although confusion with prostatic cancer is possible when one is not familiar with the histopathological appearance. We report another two cases of the glandular type of basal cell hyperplasia with immunohistochemical findings. Both lesions were composed of crowded and rather small glands with piling up of basaloid cells. They showed immunohistochemical positivity for high molecular weight cytokeratin 34 beta E12, confirming their relationship with basal cells. We detected focal positivity of these basal cells for alpha-smooth muscle actin, suggesting myoepithelial differentiation. Paucity of actin-positive smooth muscle cells in the stroma was noticed. One of the lesions showed some mild cytological atypia with prominent nucleoli and increased mitotic activity.

Aged↗
PubMed1994

New Na(+)-H+ exchange inhibitor HOE 694 improves postischemic function and high-energy phosphate resynthesis and reduces Ca2+ overload in isolated perfused rabbit heart.

BACKGROUND: Experiments were carried out using the new Na(+)-H+ exchange inhibitor (3-methylsulfonyl-4-piperidinobenzoyl)guanidine methanesulfonate (HOE 694) to assess the role of Na(+)-H+ exchange in myocardial ischemic and reperfusion injury. METHODS AND RESULTS: Three groups of rabbit hearts (n = 5 in each) were perfused with blood and were subjected to 45 minutes of global normothermic (37 degrees C) ischemia, followed by 1 hour of reperfusion. Group 1 was the control group (vehicle only); in group 2, HOE 694 (1 mumol/L) was administered before ischemia (pretreatment group); and in group 3, HOE 694 was given only during reperfusion to separate actions exerted during ischemia from those specifically obtained during reperfusion. End-diastolic pressure rise at 1 hour of reperfusion was reduced by administration of HOE 694 starting before ischemia (from 52.2 +/- 8.5 mm Hg in group 1 to 17.6 +/- 4.5 mm Hg in group 2, P < .01) or starting on reperfusion (28.8 +/- 5.4 mm Hg in group 3, P < .05 versus group 1). Left ventricular developed pressure (LVDP) and its derivative (dP/dt) recovered better in HOE 694-pretreated hearts (LVDP, 79 +/- 9.9 mm Hg in group 2 versus 24.8 +/- 10 mm Hg in group 1; dP/dt, 1580 +/- 198 mm Hg/s versus 340 +/- 221 mm Hg/s, P < .01). In hearts treated only on reperfusion, some improvement was observed, which, however, did not reach statistical significance. Coronary flow on reperfusion was higher in groups 2 and 3 compared with controls, and no "no-reflow" was observed. Two additional groups of hearts were perfused with phosphate-free Krebs-Henseleit solution to enable studies with 31P nuclear magnetic resonance (NMR). ATP was better preserved in HOE 694-pretreated (62 +/- 4.9% of preischemic value) than in control hearts (44 +/- 3.3%) at the end of 30 minutes of reperfusion, and phosphocreatine resynthesis was higher (109 +/- 3.7% versus 86 +/- 5.4%). HOE 694 did not affect the time course of intracellular acidosis during ischemia but suppressed a small alkaline overshoot occurring early in reperfusion (pH 6.96 +/- 0.02 in HOE 694-pretreated hearts versus 7.14 +/- 0.05 in control hearts). Electron microscopy with Ca2+ staining of the blood-perfused hearts showed that clumping of Ca2+ aggregates in mitochondria was prevented by HOE 694. CONCLUSIONS: Postischemic dysfunction was associated with a rise in end-diastolic pressure. This rise was effectively blocked by HOE 694. The drug was most effective when hearts were treated before ischemia, although partial protection was observed when administration was started on reperfusion. The action of HOE 694 strengthens the idea that Na(+)-H+ exchange during both ischemia and reperfusion contributes to contractile dysfunction.

Adenosine Triphosphate↗
PubMed1994

A histopathological study of deep dorsal penile vein in venogenic impotence.

We have studied the histopathology of 87 dorsal penile veins, obtained from patients who underwent a resection of the deep dorsal penile vein because of proven venous leakage. The amount of muscle tissue and of collagenous connective tissue has been numerically quantified. Special attention has been focused on the muscular/collagenization ratio. We show that this ratio is not correlated to age neither with the outcome of the operation and that no differences exist between veins in venous leakage patients and in potent patients. This study confirms that the reduction of venous outflow-the so called corporeal veno-occlusive mechanism-is probably a secondary passive phenomenon, due to smooth muscular relaxation, and mainly located within the corpora cavernosa, between the expanding sinusoidal wall and the noncompliant tunica albuginea. Our findings also strongly refute the hypothesis that polsters or other venous wall characteristics contribute to the normal physiology of the deep dorsal penile vein.

Adult↗
PubMed1994

Urethral squamous cell carcinoma associated with urethral stricture and urethroplasty.

We reviewed the few published cases of male urethral squamous cell carcinoma after urethroplasty. A new case report is added. Considering the known facts we conclude that urethral cancer following urethroplasty, performed to cure urethral stricture, is a rare complication. One must be aware of possible evolution to malignancy when this surgical procedure is not fully successful, i.e. in the case of recurring urinary obstruction or disturbed wound healing. Alarming symptoms are fistulization, abscess formation, ulceration and induration. Histopathological examination is needed, firstly before urethroplasty to exclude already existing malignant changes of the urethral mucosa and secondly whenever suspicion is raised after surgery. It is of utmost importance to diagnose a urethral carcinoma as early as possible because the cure rate in advanced stage is minimal.

Carcinoma, Squamous Cell↗
PubMed1993

Pelvi-perineal rehabilitation for dysfunctioning erections. A clinical and anatomo-physiologic study.

We have studied penile structure in 24 cadaver specimens and 155 patients have been treated for organic impotence by physiotherapy. Special attention has been focused on the closure mechanism of the corpora cavernosa during erection. We have found that the leakage factor of the corpora cavernosa is, among other things, influenced by the ischiocavernous muscles. Based on the above, we propose a model for the anatomic and physiologic basis of interference of the ischiocavernous muscles in venous occlusion during penile erection. Moreover we suggest that patients with erectile dysfunction should undergo pelvi-perineal rehabilitation in order to strengthen and control ischiocavernous muscles.

Adult↗
PubMed1991

Different patterns of pulmonary sequelae after hyaline membrane disease: heterogeneity of bronchopulmonary dysplasia? A clinicopathologic study.

In an autopsy study of 37 infants who suffered from hyaline membrane disease (HMD), two distinct patterns of pulmonary lesions could be defined. One pattern, characterized by marked interstitial fibrosis in the absence of airway abnormalities, was labelled 'interstitial-type' histology. A second type, labelled 'bronchiolar-type' histology, showed marked airway lesions and alveolar emphysema. Nine patients of each type were analysed. Nineteen other patients had a 'mixed-type' histology and were not further studied. Retrospectively, the clinical and radiological characteristics of both series were analysed. No differences in birth weight, gestational age and initial radiological HMD grade could be demonstrated. The pulmonary function of the bronchiolar-type patients however was significantly worse at the onset, and these infants needed more oxygen and ventilatory support during the first 10 days of life. They all died from respiratory failure whereas 4 patients from the interstitial group had non-pulmonary fatalities. In the bronchiolar group chest X-rays showed atelectasis and pulmonary interstitial emphysema in the early stages, and hyperinflation with bullae and irregular streaky densities in the later. Patients in the interstitial group had no or minor emphysema with more homogeneously spread densities over both lungs. We conclude that both types of evolution represent two extremes of the bronchopulmonary dysplasia spectrum.

Bronchopulmonary Dysplasia↗
PubMed1990

Transurethral microwave hyperthermia for benign prostatic hyperplasia: preliminary clinical and pathological results.

Transurethral microwave hyperthermia is a new conservative treatment modality for benign prostatic hyperplasia. We treated 15 patients with 915 MHz. microwaves delivered transurethrally by a helical applicator. Of the patients 12 showed substantial objective and subjective improvement of obstructive outflow parameters. Significant improvement in objective study parameters included increased mean flow rate (p less than 0.00021), decreased mean residual volume (p less than 0.00001) and decreased mean prostatic volume (p less than 0.0077). Analysis of patterns of failure showed chronic bladder atony, prostate asymmetry and middle lobe configuration as important factors that could explain the failure of hyperthermia in 3 patients. Toxicity was mild, consisting of bladder spasms, perineal pain, dysuria and hematuria. Hyperthermia-induced pathological changes in prostatic tissues, causing periurethral shrinking and secondary dilatation of the prostatic urethra, are described. The reported clinical results of this phase I study are preliminary due to the short followup. A phase II study to optimize transurethral hyperthermia currently is underway. A phase III study is to be phased in comparing hyperthermia with transurethral resection of the prostate.

Aged↗
PubMed1990

Neonatal haemochromatosis.

Four cases of neonatal haemochromatosis presenting as fulminant hepatic failure in the newborn were diagnosed by autopsy. In all four cases the diagnosis was made by histochemical demonstration of excessive iron deposition in hepatocytes and extrahepatic parenchymal cells, particularly pancreatic acinar epithelium, thyroid follicular epithelium and distal renal tubules. No haemosiderin was detectable in the extrahepatic mononuclear-phagocytic cells of the spleen, lymph nodes and bone marrow. The liver was the most severely affected organ. The hepatic haemosiderosis was associated with massive hepatocellular necrosis of prenatal onset in three patients, one of whom showed formation of regenerative nodules, establishing true congenital cirrhosis. Other inconstant findings included giant cell transformation, diffuse sinusoidal fibrosis with segregation of small groups of hepatocytes and cholestasis with pseudoacinar change of liver cell plates. The fetal liver disease had its onset in the late second trimester of pregnancy and was reflected clinically by severe panhypoproteinaemia with non-immune hydrops; hyperbilirubinaemia and haemorrhagic diatheses were apparent in the newborn. Neonatal haemochromatosis is a metabolic disorder, probably of autosomal recessive inheritance. The site and nature of the basic defect remain uncertain. Pathologists should be aware of this condition and its potential recurrence in subsequent pregnancies.

Female↗
PubMed1989

Uneven lipomatosis: a pitfall in pancreatic sonography.

A marked difference in echogenicity between the anterior and posterior parts of the pancreatic head was demonstrated by pancreatic ultrasound in 4 patients. This finding could not be related to local pancreatic or peripancreatic pathology. In all patients the dorsal portion of the head, including the uncinate process, appeared less echogenic than the ventral part of the head, body, and tail. The level of demarcation was identical in all 4 cases, coinciding with the expected fusion line of the embryological dorsal and ventral pancreatic origin. Pathology available in 1 patient showed an uneven lipomatosis as an explanation for this hitherto unreported observation.

Aged↗
PubMed1988

The pathology of trisomy 13 syndrome. A study of 12 cases.

Anatomical and histopathological findings in 12 cases of trisomy 13 syndrome (nine with classic full trisomy and three with trisomy 13 and an unbalanced Robertsonian 13/13 translocation) are reported. Emphasis is on the brain defects, cardiovascular anomalies, and histological organ dysplasia. Eight patients showed abnormal development of the forebrain and midline facial structures (holoprosencephaly). Cardiovascular malformations were invariably present, the leading malformation being an infundibular ventricular septal defect often in combination with dextroposition of the aorta and abnormalities of the semilunar valves. Histological abnormalities giving evidence of organ dysplasia were observed in the central nervous system, eyes, pancreas, kidneys, and ovaries. Mild cystic renal dysplasia was a constant feature. Foci of persistent nodular renal blastema were found in six cases. The pancreatic dysplasia appears to be pathognomonic for trisomy 13. These observations illustrate the importance of pathological studies in the recognition of chromosome abnormalities and, more specifically, of trisomy 13 syndrome. Based on autopsy data, trisomy 13 can be diagnosed - or ruled out - with certainty, even in the absence of karyotyping.

Abnormalities, Multiple↗