Jozef Lauweryns

PATHOGENESIS OF CONGENITAL CYSTIC ADENOMATOID MALFORMATION OF THE LUNG

Congenital cystic adenomatoid malformation is a rare developmental abnormality of the lung. In most earlier reported cases, the anatomy of the bronchial tree was poorly documented. We describe four cases studied following autopsy. Post‐mortem bronchography or serial microscopical examination showed segmental bronchial absence or atresia in each of them. Our observations provide further evidence pointing to bronchial atresia as being the primary defect leading to the development of congenital cystic adenomatoid malformation. The morphology of the lesion, i.e. the type of malformation, is determined by the extent of dysplastic lung growth beyond the atretic segment. The aetiology of the bronchial atresia is probably heterogeneous and may either represent a primary malformation, or be the result of vascular disruption.

Multiple ankyloses, facial anomalies, and pulmonary hypoplasia associated with severe antenatal spinal muscular atrophy

Two unrelated patients with multiple ankyloses, pulmonary hypoplasia, and characteristic facies syndrome had definite evidence of severe spinal muscular atrophy of prenatal onset. In addition, there were specific changes in the adrenal cortex.

The Meckel Syndrome. Pathological and Cytogenetic Observations in Eight Cases

SummaryEight new cases of Meckel syndrome, two of them occurring in the same family, are presented. Occipital encephalocele of varying extent, multicystic renal dysplasia not associated with urinary tract obstruction, and postaxial hexadactyly comprise the three basic features of this lethal syndrome with autosomal recessive inheritance. From our observations it appears that congenital hepatic fibrosis, abnormal external genitalia in male infants and a malformed tongue with lipomatous excrescences are also frequently occurring anomalies with important diagnostic value.The statement that the majority of cases of Meckel syndrome can be detected prenatally is further supported by two cases in the present series. The incidence of this syndrome may be much higher than previously thought.

Interrupted right aortic arch in DiGeorge syndrome.

The clinical and necropsy findings in four cases of interrupted right aortic arch and right descending aorta associated with DiGeorge syndrome (congenital absence or hypoplasia of the thymus and parathyroids) are described. All patients had a mirror image of type B interruption, namely a right aortic arch with reversed branching pattern and an interruption between the right common carotid and right subclavian artery. In two patients there was a doubly committed subarterial ventricular septal defect and in the two other patients there was a perimembranous septal defect. Three patients had a bicuspid aortic valve. In a consecutive series of 185 necropsies in infants and children with congenital heart disease there were no cases of interrupted right aortic arch that were not associated with DiGeorge syndrome. These observations and previous reports indicate that the concurrence of these two rare conditions is more than fortuitous. In patients with an interrupted aortic arch the clinician should be aware of the common association with DiGeorge syndrome. If the interruption is associated with a right-sided descending aorta it is highly probable that the patient has DiGeorge syndrome.

Lung metastasis of malignant epithelioid hemangioendothelioma mimicking a primary intravascular bronchioalveolar tumor. A histologic, ultrastructural, and immunohistochemical study

A 40‐year‐old woman presented with multiple nodules in both lungs and a small tumoral mass at the level of the left brachial artery. A pathologic diagnosis of pulmonary intravascular bronchioloalveolar tumor (IVBAT) and epithelioid hemangioendothelioma of the limb was established. Morphologic and immunohistochemical studies highly suggest that both tumors are manifestations of the same neoplastic process. In this case a metastatic nature of the IVBAT is suggested. The diagnosis of pulmonary IVBAT should be followed by a search for sclerosing vascular tumors elsewhere. Finally, the results substantiate the vascular origin of the IVBAT.

Morphological Characteristics of Spontaneous Endometriosis in the Baboon (Papio anubis and Papio cynocephalus)

The histopathology of spontaneous endometriosis was studied on 20 pelvic implants biopsied at laparoscopy in 15 healthy baboons. Endometriosis was confirmed by histopathology in 10 of these animals (66%). Typical (n = 3) and subtle (n = 13) endometriotic lesions were confirmed by histopathology in 100 and 61%, respectively. Suspected disease-bearing lesions (n = 4) were confirmed in 50%. Implants could be classified as active (n = 5), inactive (n = 3), atrophic (n = 2) or stromal endometriosis (n = 3). The histological findings for typical and subtle implants were similar to those reported in humans.

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 34βE12, confirming their relationship with basal cells. We detected focal positivity of these basal cells for α‐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.

THE EFFECT OF PREGNANCY ON ENDOMETRIOSIS IN BABOONS (PAPIO ANUBIS, PAPIO CYNOCEPHALUS)

Abstract.Background: This study was performed to test the hypothesis that endometriosis undergoes regression during pregnancy. Methods: This study was performed on 11 baboons with histologically proven endometriosis, housed at the Institute of Primate Research, Nairobi, Kenya. In each individual baboon paired laparoscopies were performed prior to and during pregnancy (6 during first and 5 during second trimester of gestation) with an interval of 5±3 months. During each laparoscopy the number, size and type of endometriosis implants were noted in detail on a pelvic map; the endometriosis score and stage were calculated according to the revised American Fertility Society (AFS) classification. In each baboon the observations prior to and during pregnancy were compared and analysed by Wilcoxon signed rank test (two-tailed). Results: No significant change was observed in the AFS score or stage of endometriosis, or in the number, size and type of endometriotic lesions in baboons during gestation when compared to the nonpregnant state. Conclusion: In baboons pregnancy had no significant effect on endometriosis during the first or second trimester of gestation.

Association of Meckel syndrome with M‐anisosplenia in one patient

This report concerns the concurrence in a male infant of Meckel syndrome (Dysencephalia splanchnocystica) and M‐anisosplenia. a rare variant of the Ivemark asplenia syndrome. Because of one previous report of this combination, we assume a possible etiologic relationship.

Biochemical and histochemical analysis of steroid hormone binding sites in human primary breast cancer

Mammary carcinoma tissue from 514 primary breast cancer patients were all biochemically and histochemically analyzed for both estrogen receptors and progesterone receptors. The dextran‐coated charcoal (DCC) method measured the ER and PR as defined by Scatchard analysis, ligand competition experiments and target organ specificity. The ligands, estradiol‐6‐carboxymethyloxime‐BSA‐fluoresceine isothiocyanate and hydroxyprogesteronehemisuccinate‐BSA‐tetramethylrhodamine isothiocyanate, used for histochemistry, did not bind to either ER or PR and were mainly bound to the membrane fraction of isolated breast cancer cells. Fluorescence was not specifically inhibited by estrogens or progestogens. In addition, “estrogenic” always coincided with “progestogenic” fluorescence. The binding of the fluoresceine compounds to tissue slides depended on the large steroid hormone substitution on the bovine serum albumin molecule. Clinical parameters, known to be related to ER and PR did not correlate with the histochemical results. The observations indicated the impossibility of specific steroid receptor detection by the histochemical method. Therefore, up to the present, evaluation of hormone dependency and prognosis in human breast cancer cannot be based on this approach.