Bronchogenic and alveologenic tumors in mice induced by N-nitrosopiperidine.

The aim of this study was to explore the histogenesis and carcinogenesis of pulmonary cancer induced by N-nitrosopiperidine (NPIP) in mice. NPIP is a form of N-nitrosamine found in tobacco smoke, which has been shown to be a genotoxic chemical as well as a mutagenic compound for inducing chromosome aberrations and severe clastogenicity. In this study, 80 BALB/C strain mice were injected with 0.2 mmol/kg NPIP intraperitoneally for 8 weeks, and experiments were conducted for a further 16 weeks. For the control group, 40 mice were injected with an equal volume of 0.9% NaCl. Pulmonary tissues and tumors in the NPIP-treated group were examined by light microscopy and transmission electron microscopy and compared with the control group at 4-week intervals. The mRNA levels of p53 (mutant), bcl-2, c-myc, ras, and subunits of telomerase - telomerase reverse transcriptase (TERT) and an RNA component, TR - were assayed by mPCR or RT-PCR. Twenty-two mice in the experimental group were found to develop pulmonary tumors, but none in the control group. All tumors found in the experimental group originated from alveolar type II epithelial cells. In addition, 6 of the 22 mice also developed tumors of bronchogenic origin. The expression of p53, bcl-2, c-myc, ras, and the subunits of telomerase were found to increase in all pulmonary tissues and tumors formed thereafter upon NPIP treatment. In summary, NPIP-induced mouse lung tumors exhibited morphological changes during carcinogenesis, which may be the consequence of overexpression of some genes associated with the development of carcinoma and changes in subunits of telomerase. This mouse model of lung tumor formation may be a useful tool to delineate the histogenesis and carcinogenesis of human pulmonary cancer.

Carcinoide bronquial: estudio clínico patológico de 10 casos / Bronchial carcinoid: a clinical-pathological study of 10 cases

El carcinoide bronquial representa el 1 a 5 por ciento de todos los tumores pulmonares y es el segundo más frecuente de todos los carcinoides. Constituye un grupo de neoplasias con diferenciación neuroendocrina y potencial maligno con invasión local y metástasis. El presente trabajo tiene como objetivos conocer las características clínicas y tipos de carcinoide en nuestra casuística, así como la utilidad diagnóstica de los estudios histopatológicos complementarios. Se recolectaron los casos del periodo 1988-1996 y se estudiaron con técnicas corrientes, inmunohistoquímica con anticuerpos monoclonales contra enolasa neuronal específica (ENE), sinaptofisina (SIN), cromogranina A (CRO-A) y en cuatro casos con microscopía electrónica. Se encontraron diez casos en el período, 5 mujeres y 5 hombres, con edad que varió de 18 a 74 años; 6 casos fueron formas atípicas y 4 típicas. Las localizaciones más frecuentes fueron lóbulo superior izquierdo y lóbulo inferior derecho. el 50 por ciento fueron uninodulares y el 20 por ciento multinodulares. El diagnóstico clínico se planteó en un caso. El 80 por ciento mostró argentafinidad, 70 por ciento argirofilia; 90 por ciento fueron positivos para ENE, 60 por ciento SIN, 70 por ciento CRO-A. Al microscopio electrónico todos mostraron gránulos neuroendocrinos. Los estudios complementarios utilizados permitieron confirmar el diagnóstico. Tanto la microscopia electrónica como el estudio inmunohistoquímico permiten un diagnóstico específico, especialmente cuando se utiliza un panel de anticuerpos

Bronchogenic squamous cell carcinomas with invasion along alveolar walls.

In bronchogenic squamous cell carcinoma, a growth pattern along the alveolar walls of the peripheral lung parenchyma is unusual. In order better to understand the way tumour cells invade the peripheral lung parenchyma, we studied two cases of squamous cell carcinoma with invasion along the alveolar walls (in 30% to 40% of the area surrounding the tumour). We used immunohistochemical staining with antibodies against pulmonary surfactant, apoproteins (PE-10) and collagen type IV, and electron microscopy. Tumour cells invading the peripheral lung tissue were located between one layer of type II alveolar epithelial cells and the basement membrane of the alveolar walls. These results suggest that the cells of a squamous carcinoma (unlike an adenocarcinoma) have the ability to spread along the basement membrane of the alveolar walls without destroying pre-existing normal peripheral lung parenchyma.

Characteristics of two cell lines derived from a histologically undifferentiated bronchial carcinoma expressing neuroendocrine markers.

This study investigates the characteristics of two human cell lines--1PT and 1PT VARIANT A--both derived from the same histologically undifferentiated, neuroendocrine positive, non-small cell lung carcinoma (NSCLC) and capable of growth in unsupplemented serum-free minimum essential medium. In stationary culture, the cells of both lines grew both attached to a plastic substratum and in suspension; the 1PT VARIANT A line formed three-dimensional clusters of loosely adherent cells. The cell lines differed in their DNA content, the 1PT having 1.44 times and the 1PT VARIANT A having 2.39 times the normal human diploid DNA content. Chromosome counts supported this observation, the ploidy of the 1PT and VARIANT A lines being 1.11 and 1.64, respectively. On transmission electron microscopy the cells of both lines had dense core granules and immature desmosomes, whereas only the 1PT VARIANT A line had mucin granules. Both lines formed, in nude mice, tumors that, like the original tumor from which they were derived, were histologically undifferentiated and showed local invasion. The original tumor and both lines had demonstrable neuroendocrine markers. Cytokeratins were apparent in the tumor but not the cell lines, and neurofilaments were present in the cell lines only. Staining for epithelial membrane antigen, neural cell adhesion molecule, and desmoplakin differentiated between the two lines. These lines provide a useful model for the investigation of the biology of the neuroendocrine positive subgroup of NSCLC, which is clinically important because of the possible responsiveness of these tumors to chemotherapy.

Effects of bistramide A on a non-small-cell bronchial carcinoma line.

The antiproliferative effects of bistramide A, a nitrogenous dilactam polyether from Lissoclinum bistratum Sluiter (Urochordata), were studied at the level of the cell cycle in asynchronous cells of the NSCLCN6-L16 line. Bistramide A has a dual mechanism that induces blockade in the G1 phase (compatible with differentiation properties reported elsewhere) and causes polyploidy that is suggestive of inaptitude for cytokinesis. These effects confirm the results of cytomorphology studies in electron microscopy.

High amylase activity in pleural fluid and primary bronchogenic adenocarcinoma.

We report a case of primary bronchogenic adenocarcinoma, complicated by pleural effusion, in which very high pleural amylase activity was found, whilst serum amylase was normal. Isoamylase determination showed a salivary-type amylase. Concerning the origin of this enzyme, ultrastructural study of the malignant cells obtained from the pleural fluid suggested a local amylase synthesis. The pathophysiological significance of electron-dense granules found in these cells is also discussed.

Basement membranes in bronchogenic squamous cell carcinoma: an immunohistochemical and ultrastructural study.

Basement membrane (BM) deposition at the inter-face of tumor cells and stroma was studied in 27 bronchogenic squamous cell carcinomas. Specimens from peripheral and central parts of each tumor were collected. These were frozen, formalin fixed and paraffin embedded or fixed in Karnovsky's fixative, and processed for electron microscopy. With the use of antibodies to type IV collagen and laminin, the BM was visualized by light microscopy with an indirect immunoperoxidase technique. Light microscopic findings were compared to ultrastructural observations. The peripheral parts of the tumors showed continuous BM in a recognizable preexisting alveolar pattern without evidence of invasive growth into the alveolar septa. In contrast, central parts showed highly variable BM deposition ranging from continuous to almost completely absent. Alveolar patterns were not observed in the tumor centers. The stromal compartment of the tumor centers contained many spindle cells with irregular pericellular BM-like material that could be identified ultrastructurally as myofibroblasts. Electron microscopy and immunohistochemistry yielded virtually identical results. It is concluded that invasive growth in bronchogenic squamous cell carcinomas occurs in central parts of the tumor when the tumor periphery shows expansive growth without invasion of alveolar septa. The situation is different in invasive squamous cell carcinomas originating from other organs because of anatomical differences between the lung and solid organs.

Ultraestructura de los capilares intramusculares en el paciente con carcinoma broncogénico / Capillary ultrastructure of the skeletal muscle in patients with bronchogenic carcinoma

En el presente trabajo se estudiaron los efectos del carcinoma broncogénico no tratado y sin manifestaciones metastásicas sobre la ultraestructura de los capilares del músculo QUADRICEPS FEMORIS. Para ello se emplearon biopsias provenientes de pacientes remitidos al Hospital "José Ignacio Baldo". La microspopía electrónica de transmisión reveló la existencia en las biopsias analizadas (n=7) de una amplia gama de alteraciones que comprendieron : engrosamiento y reduplicación de la membrana basal, proliferación endotelial, oclusión de la luz capilar y en algunos casos necrosis de los mismos. El infiltrado mononuclear consistió de linfocitos y macrófagos. Tales anormalidades en los capilares intramusculares podrían constituir un factor importante en la etiopatogenia de las manifestaciones clínicas musculares del paciente con carcinoma broncogénico en ausencia de metástasis

Electron microscopic observations in in situ and microinvasive bronchogenic squamous cell carcinoma.

Seventeen cases of resected in situ and microinvasive bronchogenic squamous cell carcinoma were studied by light and electron microscopy. No definite secretory differentiation was found in any case. Examination of the tumour cells in the basal layer for electron density of cytoplasm, intercellular spaces, and degree of development of cytoplasmic processes showed a variety of cells ranging from type I, where the cytoplasm was dark, development of cytoplasmic processes was good, and the intercellular spaces were large, to type III, where cytoplasmic processes and intercellular spaces were less well developed and the cells were mostly of clear cell type. The tendency to invasion was greater in type III than type I and there was also more marked cellular atypia, more extensive dissolution of basement membrane, a larger number of mitotic figures per 3000 cells in the basal layer, and greater enlargement of nuclear and cytoplasmic areas. A good rank correlation coefficient was obtained. Small dense-core granules were observed in some cases. These finding suggest the strong possibility that cell kinetics and cellular morphology are related to the development of squamous cell carcinoma.

Electron microscopy of fine needle aspiration biopsies of mediastinal and paramediastinal lesions.

The ultrastructural cytologic study of fine needle aspiration (FNA) biopsies from eight cases with mediastinal and paramediastinal lesions is reported. In these cases, electron microscopy (EM) was essential in cytologically determining the correct type of the cancer cells. The results in these cases suggest that portions of FNA biopsies from deep sites, where aspiration is difficult or requires computed tomographic scanning, should be routinely processed for plastic embedding, so that EM examination can be performed if the cells are undifferentiated, scanty or poorly preserved by light microscopic examination. The proper cytologic identification of the cell might, in fact, have a major bearing on the therapeutic choices and on the prognosis.

Electron microscopy of biopsies from bronchogenic neoplasms.

Bronchial biopsies were investigated by light microscopy (LM) and electron microscopy (EM) with the aim to evaluate if EM could contribute to the LM tumour type diagnosis. Fourty-three pairs of biopsies were comparable. A histogenetic typing, especially of light microscopically undifferentiated and unclassifiable carcinomas, was possible by EM. However, when considering the therapeutical possibilities, at present time, LM tumour classification must be regarded as fully sufficient.

Ultrastructure of tumour invasion and desmoplastic response of bronchogenic squamous cell carcinoma.

Using ultrastructural methods we studied the interaction of tumour cells and lung parenchyma in deep areas (i.e., more than about 3 mm from the tumour surface) of 50 bronchogenic squamous cell carcinomas. The tumour periphery, studied previously, had shown organized associations of tumour cells and lung epithelial cells and a surprising lack of invasion of non-epithelial tissue compartments. The deeper areas, where the tumour cells and the lung parenchyma had been in contact for longer periods, consisted of irregular groups of tumour cells and desmoplastic stroma which was very similar to granulation tissue. The deeper areas also contained many intact lung epithelial cells, arranged in compressed and distorted alveolar structures. Where non-neoplastic epithelial cells and tumour cells had direct contact, they formed common junctional complexes and basal laminae. In part of the tumours, the cells were largely devoid of a basal lamina. However, in most instances a continuous basal lamina surrounded every tumour cell group studied, even when these formed irregular strands or seemed to be completely isolated.

Bronchial mucoepidermoid carcinoma metastatic to skin. Report of a case and review of the literature.

A case of bronchial mucoepidermoid carcinoma is reported, the presentation of which was as cutaneous metastases. Histologic, histochemical, and ultrastructural features of the neoplasm are described, and the literature pertaining to bronchial mucoepidermoid carcinoma is reviewed. This case illustrates the potential for aggressive behavior in a mucoepidermoid neoplasm, the histologic features of which are considered low grade by some authors. Because such metastatic lesions may be morphologically identical to tumors that have been described as primary cutaneous mucoepidermoid carcinomas, this differential must be considered by the histopathologist confronted by such a neoplasm.

[Heterogeneity of malignant bronchial tumors. Problems of histogenesis]. / Hétérogénéité des tumeurs bronchiques malignes. Problèmes d'histogenèse.

The 1981 WHO classification of bronchial carcinoma, based on light microscopic analysis, proposed 4 principal classes: epidermoid carcinoma, adenocarcinoma, small cell carcinoma and large cell undifferentiated carcinoma. This apparently simple nosology underestimates the difficulties of classifying a good number of these tumors, due to a great diversity in appearance within the same histologic group. Experimental studies on the regeneration of bronchial epithelium, on lesions induced by irritants and carcinogens, suggest one undifferentiated cell line as the origin of all malignant proliferations, including neuro-endocrine tumours. To support this histogenetic hypothesis, an ultra-structural analysis of the carcinomas shows the existence and frequency of heterogenous forms, multi-differentiated, up to the level of individual cells. The same cell line may express several ways of differentiation simultaneously (bi or tri-partite differentiation). Equally immunohistochemical methods reveal antigenic differentiation (intermediary filaments, neuro-endocrine antigens) and establish a means of identifying different cellular constituents. These two methods have allowed real progress in the diagnosis of neuro-endocrine tumours, placing them firmly with bronchial tumours and seem particularly helpful in the analysis of undifferentiated small and large cell carcinomas. By another way, one finds in the majority of bronchial tumours the different antigens expressed, certainly following their histological type in variable degrees, yet with an antigenic (phenotypic) profile showing great similarity. This is a reflection of multi-differentiation in these tumours and appears as a direct consequence of their common histogenetic origin. Bronchial carcinomas are placed along a continuous spectrum of three parallel and/or simultaneous differentiations. They represent a single tumour having a tendency to express one or several ways of differentiation.

Metastasis of bronchogenic carcinoma to the skin involved by melanoma.

In a 52-year-old man, a cutaneous malignant melanoma developed concurrently with an adenocarcinoma of the right lung. The latter disseminated widely, and autopsy disclosed that it had also metastasized to the dermal tissue involved with the melanoma. Because it was not a metastasis into the substance of the melanoma, it was classified as an unusual type of "collision tumor" rather than a "cancer-to-cancer" metastasis.

Scanning electron microscopy in the diagnosis of bronchogenic squamous cell and small cell anaplastic carcinoma.

The authors believe that differential diagnostic aspects between poorly-differentiated squamous cell carcinoma (PDS) and small cell anaplastic carcinoma (SCA) may be shown by scanning electron microscopy (SEM) analysis of 'thick' sections from routine paraffin-embedded tissues. In 8 'sample' cases features were demonstrated which were typical of PDS (well-defined outlines of cells, intercellular bridges) and of SCA (fairly smooth cell surface, nuclei in relief, a spongy, granular-like appearance of cytoplasm).