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Diagnostic imaging of musculoskeletal tuberculosis.

In the last decade an increase in the incidence of tuberculosis has been observed, due in part to the growing number of AIDS-patients. Musculoskeletal involvement is observed in 1-3% of tuberculosis cases. Aim of this article is to describe the diagnostic imaging of musculoskeletal tuberculosis and in particular the diagnostic potentialities of conventional radiology, CT and MRI. The role of MRI in the early identification of vertebral infectious process, in the determination of its locoregional extension and sometimes in its characterization, is underlined. In peripheral osteoarticular tuberculosis both CT and MRI do not supply additional diagnostic information as compared to conventional radiology; the tuberculous process is of difficult differentiation from other degenerative, inflammatory or neoplastic processes; in any case very careful attention is mandatory to establish an early diagnosis.

Adult↗

The role of pH dynamics and the Na+/H+ antiporter in the etiopathogenesis and treatment of cancer. Two faces of the same coin--one single nature.

Looked at from the genetic point-of-view cancer represents a daunting and, frankly, confusing multiplicity of diseases (at least 100) that require an equally large variety of therapeutic strategies and substances designed to treat the particular tumor. However, when analyzed phenotypically cancer is a relatively uniform disease of very conserved 'hallmark' behaviors across the entire spectrum of tissue and genetic differences [D. Hanahan, R.A. Weinberg, Hallmarks of cancer, Cell 100 (2000) 57-70]. This suggests that cancers do, indeed, share common biochemical and physiological characteristics that are independent of the varied genetic backgrounds, and that there may be a common mechanism underlying both the neoplastic transformation/progression side and the antineoplastic/therapy side of oncology. The challenge of modern oncology is to integrate all the diverse experimental data to create a physiological/metabolic/energetic paradigm that can unite our thinking in order to understand how both neoplastic progression and therapies function. This reductionist view gives the hope that, as in chemistry and physics, it will possible to identify common underlying driving forces that define a tumor and will permit, for the first time, the actual calculated manipulation of their state. That is, a rational therapeutic design. In the present review, we present evidence, obtained from a great number of studies, for a fundamental, underlying mechanism involved in the initiation and evolution of the neoplastic process. There is an ever growing body of evidence that all the important neoplastic phenotypes are driven by an alkalization of the transformed cell, a process which seems specific for transformed cells since the same alkalinization has no effect in cells that have not been transformed. Seen in that light, different fields of cancer research, from etiopathogenesis, cancer cell metabolism and neovascularization, to multiple drug resistance (MDR), selective apoptosis, modern cancer chemotherapy and the spontaneous regression of cancer (SRC) all appear to have in common a pivotal characteristic, the aberrant regulation of hydrogen ion dynamics [S. Harguindey, J.L. Pedraz, R. García Cañero, J. Pérez de Diego, E.J. Cragoe Jr., Hydrogen ion-dependent oncogenesis and parallel new avenues to cancer prevention and treatment using a H+-mediated unifying approach: pH-related and pH-unrelated mechanisms, Crit. Rev. Oncog. 6 (1) (1995) 1-33]. Cancer cells have an acid-base disturbance that is completely different than observed in normal tissues and that increases in correspondence with increasing neoplastic state: an interstitial acid microenvironment linked to an intracellular alkalosis.

Animals↗

The etiopathogenesis of breast cancer prevention.

Breast cancer, the most frequent malignancy diagnosed in women, continues to increase in incidence in all industrialized nations. The fact that this disease becomes incurable once it has spread to regional or distant sites indicates that its complexity is beyond our present level of knowledge. A better understanding of the etiopathogenesis and biology of breast cancer is required in order to develop a rational basis for its prevention and therapy. The observation that early parity reduces the risk of developing breast cancer indicates that reproductive and hormonal conditions might play an important role in its prevention. The elucidation of the mechanisms mediating this protection requires the availability of adequate experimental models. The induction of rat mammary carcinomas with chemical carcinogens has proven to be useful for these purposes, especially since, in this model, full-term pregnancy or treatment of virgin rats with a placental hormone, human chorionic gonadotropin (hCG), prior to the administration of the carcinogen protects the mammary gland from tumor development. Since both pregnancy and hCG treatment induce differentiation of the mammary gland, this process is considered to be essential for the inhibition of the neoplastic process. The possibility of preventing breast cancer by treating young nulliparous females with hormones that mimic a full term pregnancy is of practical interest to the human female population, but it requires a thorough knowledge of the development of the human breast. Our studies indicate that the breast of postpubertal nulliparous women is composed of lobular structures reflecting different stages of development. Type I lobules are the most undifferentiated. Type 2 lobules evolve from the previous ones; they are composed of a higher number of ductular structures per lobule. They progress to lobules types 3 and 4, which are present in the breast during pregnancy and lactation. The type 1 lobule, considered to be the site of origin of ductal carcinomas, predominates in the breast of nulliparous women of all ages. In parous women, the type 3 lobule is the most frequent. Primary cultures derived from breast tissues composed of type 1 lobules express phenotypes of cell transformation not observed in cells derived from type 3 lobules. These data acquire relevance in the light that women with a history of early pregnancy are at a lower risk of developing breast cancer than nulliparous women, an effect attributed to differences in the degree of differentiation of the breast. Pregnancy furthers the differentiation of type 1 lobules to type 3, making them refractory to neoplastic transformation.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Mycosis fungoides: classic disease and variant presentations.

Mycosis fungoides is a peripheral non-Hodgkin's T-cell neoplastic process, representing the most common type of primary cutaneous malignant lymphoma. Neoplastic lesions classically show skin predilection and characteristic clinical and histologic features in patch, plaque, and tumor stages. In addition, several clinicopathologic variants of mycosis fungoides have been delineated, including poikiloderma atrophicans vasculare (parapsoriasis variegata), Sézary syndrome, granulomatous mycosis fungoides, hypopigmented mycosis fungoides, folliculocentric mycosis fungoides, syringotropic mycosis fungoides, and Woringer Kolopp disease. We will review the salient features of patch, plaque, and tumor stage mycosis fungoides in this article and follow with a discussion of these variant clinicopathologic presentations and of therapeutic modalities.

Diagnosis, Differential↗

[Iron deposits, cell populations and proliferative activity in pigmented villonodular synovitis of the knee joint].

Pigmented villonodular synovitis (PVNS) of the knee is a tumor-like process of uncertain nature. A chronic inflammation as well as a neoplastic process have been proposed in the literature. The aim of our study was to characterise the prevalent inflammatory cells, the proliferating cell populations, and the iron deposit distribution in PVNS in order to get insights into pathogenetically relevant processes of this condition. Thirteen cases of PVNS of the knee as well as 8 normal controls were analysed histochemically for iron deposits and immunohistochemically for the distribution of vascular structures and inflammatory cell populations. Collagen type I expressing fibroblastic cells were identified by in situ hybridization. The proliferative cell compartment was characterized using MIB-1 staining. Our analysis showed no correlation between intra- or extracellular iron deposits and proliferation, giant cell formation, vascularity, number of CD 68-positive cells, and foam cell formation. Instead, iron deposits were associated with collagen matrix formation. All PVNS specimens showed a significant increase of chronic inflammatory infiltrates compared to all normal synovial membrane specimens investigated. The identification of the proliferative cell compartments showed that besides fibroblastic cells many of the mononuclear, partly CD 68 positive cells were Ki-67 positive. Foam cells, iron-loaded cells, and giant cells were, however, negative for the Ki-67 antigen. PVNS appears to originate from the interplay of proliferating, partly CD 68 positive mononuclear cells and fibroblasts, both activated by an excessive iron load. Giant cells probably develop by fusion of CD 68-positive histiocytic cells. Foam cells are most likely secondary to fatty tissue destruction.

Antigens, CD↗

Lung cancer in the elderly--increasing epidemiological problem of 21st century.

Lung cancer is the second most common malignant neoplasm after prostate and breast cancers. It is the most frequent cause of death related to neoplasms. The elderly people over 65, are the most numerous population suffering from lung cancer. Risk of incidence and death increases with aging process. In majority of patients, diagnose is established in highly advanced neoplastic process. More than 80% of all types of lung cancers make non-small cell lung cancer (NSCLC) and less than 20%--small cell lung cancer (SCLC). The choice of the managment must be individually considered and should be based on the stage of cancer clinical advance, clinical and functional status, concomitant diseases, nutritional status, cognitive functions. The patients age is not a contradiction for the introducement of the treatment. Surgical treatment is a method by choice at the early stages of NSCLC. Radical radiotherapy should be introduced in the elderly disqualified from the operation. Single-agent chemotherapy seems to be benficial for the elderly with advanced NSCLC in good general condition, mainly due to less toxicity and satisfactory the survival rate. In the cases of SCLC polychemotherapy with prophylactic brain radiation is the first-line managment. Unfortunately, the effectivity of the therapy is occupied by its toxicity. Still frequent occurrence and late diagnosis of lung cancer, high mortality, low efficiency of chemo- and radiotherapy causes the necessity of newer research for more effective screening methods, more effective and safer lung cancer treatment schemes for the elderly.

Age Factors↗

Infection versus tumor in the spine: criteria for distinction with CT.

To develop criteria to distinguish among pyogenic infection, nonpyogenic infection, and neoplastic processes in the spine by means of computed tomography (CT), the authors retrospectively analyzed 17 cases of pyogenic infection (20 sites), 40 cases of neoplastic disease (56 sites), and five cases of granulomatous infection (eight sites). Reliable criteria for pyogenic infection were complete prevertebral soft-tissue involvement, diffuse osteolytic destruction, gas within both bone and soft tissue, and a process centering on an intervertebral disk. Neoplastic disease was characterized by posterior element involvement, partial or absent prevertebral soft-tissue swelling, and osteoblastic alterations. In a limited number of cases, nonpyogenic infection was characterized by focal lytic bone involvement and marginal sclerosis. Blinded testing of these criteria indicated potential for improved diagnostic accuracy in clinical practice.

Humans↗

Deletion and translocation involving chromosome 3 (p14) in two tumorigenic Kaposi's sarcoma cell lines.

BACKGROUND: Two neoplastic Kaposi's sarcoma (KS) cell lines, KS Y-1 (derived from a patient with KS associated with acquired immunodeficiency syndrome) and KS SLK (derived from an immunosuppressed patient with a renal transplant and KS or iatrogenic KS), have been shown to have abnormal chromosome constitution and to require no exogenous growth factors. They produce malignant tumors in immunodeficient mice. In contrast, all other cell cultures prepared in the past from KS specimens have shown to have normal diploid characteristics are hyperplastic, and depends on cytokines for growth, but they do not produce malignant tumors in immunodeficient mice. PURPOSE: We investigated whether the chromosomal changes that occurred in these KS cell lines were random contribute to the pathogenesis of KS. METHODS: We used the conventional G-banding technique and fluorescence in sti hybridization to identify structural and numerical chromosomal changes in the KS cell lines. RESULTS: We demonstrated that both cell lines are aneuploid and have some additional features in common, i.e., loss of copies of chromosomes 14 and 21 and nonrandom translocations and deletions in the short arm of chromosome 3 at region 3p14. These KS cell lines also exhibits loss of heterozygosity of loci at region 3p14-ter. CONCLUSION: This is the first time nonrandom chromosomal alterations have been described in KS neoplastic cells. On the basis of information available on other available on other cancers, the chromosome 3 alterations observed here can be expected to contribute to the neoplastic process in KS. IMPLICATIONS: Future research should focus on the identification cytogenetic markers, thus facilitating generation of specific molecular probes for detecting neoplastic cells early in the disease process.

Acquired Immunodeficiency Syndrome↗

[Diagnosis and surgical therapy of diffuse pigmented villonodular synovitis of the hip joint].

Pigmented villonodular synovitis (PVNS) of the hip is a monoarticular proliferative process involving the synovial membrane. A chronic inflammation as well as a neoplastic process have been proposed in the literature. PVNS is usually found in adults aged 20-50 years, without sex predilection. The knee is by far the commonest location, followed by the hip. We present a detailed case report of a 25-year-old man with PVNS of the hip. The physical examination was completely normal. Radiographs of the hip show erosions in the head and neck of the femur and the acetabulum. Magnetic resonance imaging showed a suspected malignant soft tissue mass involving the hip joint. The diagnosis of PVNS was confirmed by arthroscopy and biopsy, and the treatment of choice was an open synovectomy. One year after the operation the clinical examination was normal.

Adult↗

Distribution of actin filaments in human malignant keratinocytes.

Distribution of actin filaments in human malignant keratinocytes was examined by immunofluorescence staining. The primary cultures were obtained from a squamous cell carcinoma, a basal cell carcinoma, and Bowen's disease. Rhodamine-phalloidin staining revealed that actin filaments were occasionally organized to form stress fibers, many short bundles with a ripple appearance, and regular arrays of actin patches. Some of these structures appeared in untransformed keratinocytes as a result of a brief exposure to a tumor promotor, TPA. These findings suggest that regulation of actin functions is involved in neoplastic processes from the very early stages and that alteration is persistent in neoplastic cells.

Actins↗

Mucin gene expression in human embryonic and fetal intestine.

BACKGROUND: The intestinal epithelium is covered by a continuous layer of mucus which is secreted by well differentiated epithelial cells. Disregulation of the expression of mucins has been reported to have possible implications in the neoplastic process which affects intestinal mucosae. It is well known that preneoplastic and neoplastic tissues can express fetal phenotypic characteristics. AIMS: To assess whether the expression of mucin genes in the intestinal tract is linked to the stage of cellular differentiation and tissue development, by studying the expression of six mucin genes in human fetal small intestine and colon, and also adult tissues. METHODS: In situ hybridisation was used to study mRNA expression of MUC2, MUC3, MUC4, MUC5B, MUC5AC, and MUC6 in 32 human embryos and fetuses (6.5-27 weeks gestation). Normal adult mucosae were used as controls. RESULTS: Three mucin genes, MUC2, MUC4, and MUC5AC, were differently expressed in fetal intestine compared with expression in normal adults. CONCLUSION: These differences in mucin gene expression suggest a possible regulatory role for these products in intestinal epithelial cell differentiation.

Adult↗

Passive seeding in metanephric adenoma: a review of pseudometastatic lesions in perinephric lymph nodes.

Lymph node involvement derived from a discrete neoplastic process fundamentally implies tumor malignancy. However, rarely, inconsequential passive transport of benign neoplastic cells to the lymph node can occur and may cause confusion as to the nature of the neoplasm (ie, malignant vs benign). We describe a 10-cm right renal metanephric adenoma incidentally discovered in a 30-year-old woman during cesarean section for a triplet pregnancy. Subsequent nephrectomy following an equivocal needle biopsy diagnosis showed histologic features classic for metanephric adenoma, including the lack of cytologic atypia and mitoses. Necrosis present in this lesion appeared to be secondary to tumor physical disruption. The tumor cells were positive for Wilms tumor 1 (WT1) antigen, pankeratin, and CD57, focally positive for epithelial membrane antigen, and negative for cytokeratin 7, cytokeratin 34betaE12, and CD56. Electron microscopy confirmed the tumor's epithelial nature, and cytogenetics revealed a diploid 46XX karyotype. The tumor proliferation index with Ki-67 was only 3% to 5% and the proliferating cell nuclear antigen index was 0%. A single, concurrently resected hilar lymph node contained scattered subcapsular, sinusoidal, and focally intralymphovascular psammoma bodies along with occasional adherent epithelial cells. These cells were highlighted by pankeratin but were nonreactive to WT1 antigen, similar to the nonviable cells in the primary tumor. Clinical surveillance and follow-up showed no disease recurrence 4 years after nephrectomy. We postulate that the lymph node inclusions found in this case represent passive transport of neoplastic cells to the lymph node following manipulation of the renal mass. We conclude that this phenomenon is understudied and underrecognized and can easily be mistaken for metastasis.

Adenoma↗

[Morphologic and molecular-genetic characteristics of keratinization and apoptosis in squamous cell lung carcinoma].

46 samples of squamous-cell lung carcinoma (SqCLC) from surgical patients were examined for biomolecular tumor markers (pancytokeratins, c-myc, p53, bcl-2, Bax, Ki-67, IGF-system) and apoptosis. Keratinization appeared an independent from apoptosis type of programmed cell death. It relates to cell death by differentiation, is followed by accumulation of c-fos, c-myc, Bax, IGF-II, IGFBP-2, IGFBP-5 this indicating their involvement in the regulation of this process. High level of apoptosis does not determine positive prognosis of the neoplastic process as it is not a single variant of programmed cell death in SqCLC. Malignant grade of SqCLC depends upon correlation between the proliferative processes and various types of cell death. Better prognosis of well and moderately differentiated SqCLC (as compared to poorly differentiated carcinomas) may be due to the fact that high proliferative activity of the tumor cells is balanced by their death by keratinization.

Apoptosis↗

Intraoperative consultation for nervous system lesions.

The pathologist responsible for nervous system intraoperative consultations must know basics of the clinical history, details of the location and imaging characteristics of the lesion, and must be familiar with known clinicopathologic entities. Although cytologic and frozen section techniques have not changed significantly in the past 15 years, significant advancements in neuroimaging have greatly improved the ability to generate an accurate preoperative differential diagnosis. Such information can greatly aid the pathologist during intraoperative consultation. This review concerns the intraoperative cytologic and frozen section findings of the major clinicopathologic entities encountered in surgical neuropathology. While neoplastic processes of the central nervous system will be emphasized, important non-neoplastic conditions that mimic brain tumors will also be covered. A basic clinicopathologic approach to successful neurosurgical intra-operative consultation is provided.

Adult↗

[Necrosis of the bone marrow and cancer].

Bone marrow necrosis (BMN) is a rare complication and is characterized by the presence of an eosinophilic amorphous material in the bone marrow. The clinical, analytical and histological characteristics of 4 patients with BMN associated to a neoplastic process are described. One of them was a gastric cancer but the neoplastic origin could not de determined in the other three cases. Three patients presented bone pain, but in all four patients thrombopenia, anemia, leuko-erythroblastic reaction and elevated LDH was found. A literature review is carried out and the possible physiopathological mechanisms are discussed.

Adult↗

[Computed tomography in leptomeningeal and ventricular spread of primary brain tumors (author's transl)].

Of 8000 consecutive patients studied with computed tomography, 10 patients with primary intracranial tumors (germinoma, medulloblastoma, malignant teratoma and glioblastoma) showed ventricular or leptomeningeal spread of the tumor cells. In patients with leptomeningeal spread, computed tomography showed obliteration of basal cisterns and sulci with isodense or slightly hyperdense mass, which was markedly enhanced following administration of the contrast medium. In cases of ventricular spread, a narrow zone of high density was noted on the ependymal surface, and it was also markedly enhanced with the contrast medium. Similar CT scan appearance of contrast enhancement in the subarachnoid space or in the ventricular surface was, however, noted also in the infectious processes such as basal arachnoiditis or ependymitis, and the differentiation of the neoplastic process from the infectious lesions seemed impossible based on the CT scan appearance alone.

Adolescent↗

p53 expression in sweat gland tumors.

We analyzed the expression of p53 in 74 cutaneous adnexal tumors, with enhancement of the detection by incubation of the slides in the microwave. The immunostaining in benign tumors was almost uniformly negative as we found p53-positivity only in one poroma, one nodular hidradenoma, and one case of syringocystadenoma papilliferum (amongst 13 spiradenomas, 9 cylindromas, 12 nodular hidradenomas, 7 poromas, 6 syringomas, 7 syringocystadenomas papilliferum, 2 papillary tubular adenomas and 4 chondroid syringomas). These results contrasted with the widespread p53 overexpression, which was revealed in the sweat gland carcinomas. All spiradenocarcinomas (3), malignant nodular hidradenoma (1), apocrine hidradenocarcinoma (1), and malignant syringoadenoma (1) showed a strong reaction to anti-p53 antibody. Two of three eccrine hidradenocarcinomas, and two of three porocarcinomas presented p53 overexpression, whereas in one case of malignant cylindroma and adenoid cystic carcinoma we did not find p53-positivity. The results of the study indicate an important role, that p53 protein plays in the malignant sweat gland tumors in comparison to their benign counterparts, but reveal that its overexpression may also occur in the reactive and benign neoplastic processes.

Gene Expression Regulation, Neoplastic↗

Perspectives in gene therapy.

Gene therapy is understood to be both the restitution of genetic alterations caused by mutation or deletion and the control of overexpressed genes. The concept of gene therapy can also encompass molecular strategies to induce cell death in tumor cell by either the so-called "suicided genes" or by certain viral genes that induce a more selective cell death among the transformed cells. The prospect for the clinical application of gene therapy are enormous and, at least theoretically, its utilization can be extended to a number of diseases known to have a genetic basis, and to neoplastic processes. This review summarizes some of the projects that are currently underway involving neoplastic diseases, liver diseases, hematopoietic cells and respiratory tract cells. The results of most of the ongoing protocols are not yet conclusive, and presumibly, their clinical application is still some years away. One of the major limitations is the method of introducing the genetic sequences into the cells and achieving their constitutive expression by the cells. For ethical reasons, this approach should not be done in germ cells, but at the level of the tissue or cells most closely involved in the development of each gene-based disease. The methods employed in gene therapy are discussed, focusing on those mediated by the application of viral vectors, as well as those requiring the use of liposomes and others.

Animals↗