Investigative & cell pathology最新文献

Morphological and histochemical studies on APUD-cells in the lung epithelium are reviewed. Common features of these cells are their capacity to produce and store amine, their argyrophilia and their characteristic cytoplasmic secretory granules. Based on the fine structural morphology of the secretory granules three types of cells were observed in human foetal lung. In the human adult lung, endocrine cells were few in number and widely scattered. Contact between endocrine cells and nerves was never seen. One 'function' of endocrine cells in the human adult lung may be to act as precursor cells for carcinoid tumours and small cell anaplastic carcinomas (the APUDomas of the lung).

Development of the secondary palate was studied in the chick embryo using light and electron microscopic and histochemical techniques. The palatal shelves develop as horizontal outgrowths of the maxilla on day 6 of incubation (HH stage 29). During the next 2 days (HH stages 30-33) the shelves continue their growth toward the midline, and on day 9 (HH stage 34) they approximate. At no time do the approximating shelves form direct contacts. Ultrastructural and histochemical observations indicate that the midline epithelia of the opposite shelves differentiate into a stratified squamous pattern. Unlike rodents and humans, the midline epithelial cells of the chick embryonic palate are not programmed to die. Other features of cellular differentiation such as the appearance of intracytoplasmic tonofilaments and glycogen, seen in species where palatal fusion occurs, were absent during palatogenesis in the chick. It is suggested that morphogenesis of the palate in chick embryos is different from that in the rodents, primates and humans. These differences are attributed to the pattern of subcellular differentiation in the palatal tissues.

The population density of alveolar macrophages was measured in the lungs of hypoxic rats, in rats which had recovered from a period of hypoxia, and in untreated controls. Alveolar macrophages were most numerous in hypoxic animals. The recovery group contained fewer macrophages than the hypoxic group but more than the controls. In the hypoxic animals the distribution of alveolar macrophages was not homogeneous either within an individual rat or amongst the group as a whole. This suggests that the increase in their number may be stimulated by the secondary effects of hypoxia rather than by its direct interference with their metabolism.

Carcinoembryonic antigen (CEA) was measured in the plasma by radioimmunoassay in 80 patients who were referred because of an apparently resectable lung cancer. There was no correlation between the initial CEA level and survival in patient whose tumours were found to be inoperable or had metastasized, with only 2 of 37 patients surviving longer than 2 years. Following a curative resection, the median survival for patients with initial CEA greater than 40 micrograms l-1 was 6 months compared to 14 months for those with CEA in the range 20-40 micrograms l-1, while 56 per cent of those with CEA less than 20 micrograms l-1 are still alive at 2 years. This trend was found to be highly significant (P < 0.005). Twenty-five per cent of all patients had an initial CEA greater than 40 micrograms l-1 and this was associated with a poor prognosis, despite complete surgical removal of the primary tumour. Such elevations, if discovered in the preoperative assessment, indicate a need for a thorough search for metastases.

A series of 200 consecutive breast cancers as studied retrospectively. All of the diagnoses were reviewed without knowledge of the initial response; special attention was given to the true scirrhous carcinoma of the female breast, a special form of infiltrating duct carcinoma. Seven cases, an incidence of 3.5 per cent, fulfilled the diagnostic criteria: dense and hyaline connective tissue stroma, evenly distributed throughout the tumour and at its borders and which compressed pleomorphic and scanty carcinoma cells, almost without duct formation. Ten cases, an incidence of 5.0 per cent, were initially diagnosed as scirrhous tumours but have been reclassified as pseudo-scirrhous cancers. The commonest error seems to be the confusion between true scirrhous mammary cancer and infiltrating lobular carcinoma.

Thirty adrenal glands from patients with adreno-leukodystrophy (ALD) have been studied by light microscopy, three by enzyme histochemistry, three by electron microscopy and two by tissue culture. Cytoplasmic ballooning and striations result from proliferation of smooth endoplasmic reticulum and accumulations of lamellar-lipid profiles and clear clefts (crystalloids). Striated adrenocortical cells, the only pathognomonic adrenal lesion in ALD, display cytoplasmic lamellae, decreased amounts of rough endoplasmic reticulum and depression of several enzymes (alpha-glycerophosphate dehydrogenase, 3 beta-hydroxysteroid dehydrogenase and TPNH diaphorase). The striated cells also demonstrate decreased ability to adapt to changes in microenvironment, both in vivo and in vitro. A blunted response by striated cells to focal peripheral cytolysis leads to cytoplasmic erosion, atrophy and macrovacuoles. ACTH has a pivotal role in the evolution of these lesions. We propose that the pathognomonic lamellae of ALD basically represent bilayers or bimolecular leaflets of very long chain saturated fatty acids, while lamellar-lipid profiles and clefts contain cholesterol esterified to these abnormal fatty acids. The similarity of lamellar-lipid profiles of ALD to cytoplasmic lesions induced by long chain saturated fatty acids suggests that the very long chain saturated fatty acids isolated in ALD are cytotoxic and are responsible for adrenocortical cell dysfunction in this disease.

Patterns of mucus secretion were investigated, by histochemical methods, in 24 colectomy specimens resected for familial polyposis coli. In this pre-malignant condition, mucus secretion contained an increased proportion of sialomucins as compared with normal colonic mucosa where sulphomucins predominate. These mucin changes (a) were more extensive in the left colon than in the right; (b) although consistently present in the mucosa adjacent to carcinomas, independent of their site, and around large polyps, they were also seen in patches of mucosa distant from the neoplastic growth; (c) they were more marked in the non-involved mucosa from patients who had developed carcinoma than in the non-cancer group. It was not possible to relate the type of mucin secreted and the degree of dysplasia. Similar alterations in mucus secretion have been previously described in colonic mucosa harbouring carcinoma both in humans and experimentally in rats, suggesting a relationship between altered glycoprotein synthesis and malignancy. The present results add further evidence to this hypothesis.

Fine needle aspiration biopsy cytology is a simple technique for the outpatient diagnosis of subcutaneous malignancies. It is most useful for breast tumours but is also an aid in the clinical assessment of thyroid, salivary glands and lymph nodes and with the use of a special needle, the prostate. This paper describes the technique, briefly reviews the criteria for malignancy, the dangers of false positive and the inevitability of false negative results. Nevertheless in a clinical context, it is a useful technique that helps clinicians and their patients.

The epithelium bordering gastric carcinoma may show altered patterns of mucin secretion. The development of adenocarcinoma in the rat stomach was studied histochemically to determine whether similar mucin changes might precede malignant transformation. Male Wistar rats were fed N-methyl-N'-nitro-N-nitrosoguanidine (83 mg/l) ad libitum for 7 months. The stomachs were examined histologically and by special methods to distinguish neutral and acid mucins. Hyperplasia was observed as an early change in both antrum and body and was characterized by lengthening of foveolae and neck zones. This was accompanied by increased acid mucin secretion. Dysplastic change began in the proliferating neck zone of hyperplastic foci. These findings suggest that altered mucus secretion may be a feature of early malignant change.