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PubMed2003

Differentiating a chronic hyperplastic mass from pancreatic cancer: a challenge remaining in multidetector CT of the pancreas.

A multitude of clinical symptoms originate from pancreatic inflammatory or neoplastic processes due to their highly complex composition, function, and anatomic relationships to adjacent organs as well as the heterogeneous patterns of vascular perfusion and neural innervation of the pancreatic gland which complicate an early and precise diagnosis. Whereas early assessment of inflammatory or neoplastic pancreatic processes is a prerequisite for a successful curative approach, the classical radiologic signs of chronic pancreatitis and pancreatic carcinoma show significant similarities. This article provides an overview of the pathogenesis and imaging findings in chronic pancreatitis and pancreatic cancer, including some new approaches for visualizing the subtle but distinct differences between these two entities.

Adenocarcinoma↗
PubMedDate not supplied

Growth and progression of head and neck cancer: a report of the Upper Aerodigestive Cancer Task Force Workshop.

Factors governing the initiation, growth, and progression of squamous cell carcinoma were the focus of a recent Upper Aerodigestive Cancer Task Force workshop sponsored by the National Cancer Institute. The goal of the daylong workshop was to identify critical research concepts in head and neck cancer biology. Discussed were the multistep processes potentially involved in tumor evolution, including the role of carcinogens, viral promotors, host and tumor karyotypes, microenvironment growth factors and growth factor receptors, as well as host/tumor components inherent to the metastatic process. Concepts developed from research in other neoplastic processes but potentially relevant to head and neck cancer were emphasized. The process of identifying critical research directions is the first step by the National Cancer Institute in program development designed to advance the treatment of head and neck cancer.

Carcinogens↗
PubMed2006

Multicentric peripheral ossifying fibroma.

Peripheral ossifying fibroma (POF) is a common solitary gingival growth thought to arise from the periodontal ligament. Though the etiology of POF remains unknown, some investigators consider it an inflammatory or reactive process, while others suggest it is a neoplastic process. In this report, we present and discuss a unique case of multicentric POF, affecting the maxillary and mandibular gingiva of a 49-year-old Caucasian female with meticulous oral hygiene and routine dental care. Though biopsy samples from multiple sites revealed similar histopathologic features, consistent with POF, the fact that there was a multicentric presentation is a unique phenomenon for this lesion. Multicentric lesions presenting in the oral and maxillofacial region are not typical, but have been observed in conditions associated with known genetic mutations, such as nevoid basal cell carcinoma syndrome (multiple odontogenic keratocysts), multiple endocrine neoplasia type II (multiple neuromas), neurofibromatosis (multiple neurofibromas) and Gardner syndrome (multiple neoplasms). This case is the first one to demonstrate that there may be a multicentric variant of POF that has not been previously recognized, and given the clinical presentation and multifocal nature of disease, the lesions in this patient are likely the result of genetic mutation(s) that predisposes to gingival soft tissue overgrowths containing mineralized product.

Female↗
PubMed1991

The molecular progression of plutonium-239-induced rat lung carcinogenesis: Ki-ras expression and activation.

Specific, transforming point mutations of ras and alterations in ras expression have been associated with many neoplastic processes, and their presence may be pivotal in neoplastic transformation. Our objective were to evaluate the molecular and genetic alterations of Ki-ras in preneoplastic foci and neoplasms in the lungs of rats that inhaled 239PuO2 aerosols. Histologically classified pulmonary lesions were evaluated by in vitro nucleic acid amplification, oligonucleotide hybridization, and direct nucleic acid sequencing for activating Ki-ras point mutations. We evaluated ras expression in similar lesions using immunohistochemistry and in situ hybridization. Specific Ki-ras point mutations were present in 46% of the radiation-induced malignant neoplasms. Spontaneous pulmonary neoplasms, which are rare in rats, had similar activating mutations and frequencies (40%). We found similar mutation frequencies in radiation-induced adenomas and foci of alveolar epithelial hyperplasia. No mutations were identified in normal lung tissue. Ras expression in hyperplastic lesions and neoplasms was similar to that observed in normal pulmonary epithelia. These findings suggest that Ki-ras activation, not alterations in expression, is an early lesion associated with many radiation-induced, proliferative pulmonary lesions and that this molecular alteration may be an important component of both radiation-induced and spontaneous pulmonary carcinogenesis in the rat.

Animals↗
PubMed1990

Investigation of the effect of hydrogen peroxide on the chromosomes of young and elderly individuals.

Active oxygen species have been considered to be responsible for the aging process and for the induction and initiation of neoplastic processes. The effect of hydrogen peroxide, an active oxygen species, was investigated in the chromosomes of three young women (20-21 years of age) and of three elderly women (73-79 years of age) in a culture medium favorable to the appearance of folate-sensitive fragile sites. Hydrogen peroxide at a final concentration of 5 X 10(-6) during the final hours of culture caused a significant increase in hypodiploidy and structural aberrations, chromatid gaps in particular, only in the cultures from the three elderly women, suggesting that the chromosomes of older women are more sensitive to this agent than those of younger women. The preferential chromosome loss in both treated and untreated cultures from the elderly women involved chromosome X. The preferential sites for structural aberrations were 9p12, a constitutive heterochromatin site and 6q21, where the gene of mitochondrial superoxide dismutase, an enzyme involved in antioxidant processes in the cell, is located. Hydrogen peroxide significantly intensified the effect naturally occurring in the cells of elderly persons, such as hypodiploidy and increased structural aberrations, thus acting at the chromosome level in a manner similar to that of the natural aging process of the organism.

Adult↗
PubMed1997

Human neoplastic Schwann cells: changes in the expression of neurotrophins and their low-affinity receptor p75.

Neurotrophins are known to influence Schwann cells during development and to promote peripheral nerve regeneration after axonal damage. In neoplastic conditions. Schwann cells from experimentally-induced schwannomas appear to retain their responsiveness to nerve growth factor (NGF), although the role of neurotrophins in the neoplastic process in poorly understood. In this study, human neoplastic Schwann cells (five cases of acoustic schwannoma and two cases of malignant peripheral nerve sheath tumours [MPNST]) were investigated for the expression in situ of molecules of the neurotrophin system. In particular, we studied the 75 kDa low-affinity receptor (p75) and the mRNA for its ligands, NGF and neurotrophin-3 (NT-3). By immunohistochemistry, the p75 receptor was found to be the present at high levels in Schwann cells from acoustic schwannomas, whereas it was very weak or absent in MPNST. Messenger RNA for NGF and NT-3 was detected by reverse transcriptase in situ polymerase chain reaction technique and showed the same fluctuation of p75, being up-regulated in acoustic schwannomas and very weak or absent in MPNST. In normal non-neoplastic tissue, no detectable amounts of either ligand or receptor were observed. Our results indicate that changes in the expression of neurotrophins and their p75 receptor occurred during the neoplastic transformation of Schwann cells. In benign schwannomas, such changes are likely to reflect the loss of axonal contact, while in MPNST they may be related to a complete derangement of cell machinery in the tumour cells.

Adult↗
PubMed2004

"Stromatogenesis" and tumor progression.

"Stromatogenesis" is the formation of new stroma occurring, in parallel with the neoplastic process, at sites of active tumor invasion, i.e., at the free surface of a developing exophytic tumor, at the invading tumor front of an advancing endophytic tumor, and at sites of tumor metastasis, wherein the newly formed stroma disrupts the continuity of normal structures, cleaving paths for the invading tumor cells. Stroma is also present at the heart of the tumor, but only as a secondary event following tumor advancement and subsequent incorporation of its periphery into inner tumor areas. The new stroma, composed of stromal cells and extracellular matrix (ECM), is loose and edematous at the expanding tumor fronts, and rather dense in central tumor areas and sites of tumor metastasis. The stromal cells facing tumor invasion are intensely proliferating (high MIB-1 index) spindle-shaped cells, alpha-smooth muscle actin positive, and loaded with thymidine phosphorylase (TP) and SPARC (secreted protein acidic and rich in cysteine). The associated ECM is rich in collagen III, SPARC, and new blood vessels (CD31) but is depleted of collagen I and fibronectin. These constitutional changes render stromatogenesis amenable to tumor cell invasion and are, in cases of incipient neoplasia, a prospective criterion of early stromal invasion. Other stromal cell or ECM constituents, such as the lactate dehydrogenase-5 (LDH-5), the acidic fibroblast growth factor (aFGF), the basic FGF (bFGF), and the collagens II and IV, remain unchanged, and others are negative: myosin, desmin, S-100 protein and epidermal growth factor receptor (EGFR). The mechanism of stromatogenesis is obscure but is probably stimulated by specific stromatogenic growth factors, released by neoplastic and inflammatory cells. It appears that the process is neither neoplastic nor reactive, but rather is a, hereto unexplained, phenomenon of host's complicity in tumor progression.

Biomarkers, Tumor↗
PubMed2005

Cytochrome P450 aromatase expression in human seminoma.

BACKGROUND: The enzyme cytochrome P450 aromatase, catalysing the conversion of androgens into estrogens, has been detected in normal human testicular cells suggesting a physiological role of local estrogen biosynthesis on spermatogenesis control. Estrogens, regulating cell growth and apoptosis, can also be involved in tumorigenesis process, but the possible link between estrogens and testicular neoplastic process is, up to now, scarcely known. This study examined aromatase expression in human seminoma, which is the most common germ cell tumour of the testis. METHODS: The tumour-bearing testes were obtained from 20 patients with classic seminoma undergoing to therapeutic orchidectomy. Paraffin embedded tissues were processed for immunohistochemistry using a mouse monoclonal antibody generated against human placental cytochrome P450 arom, as primary antibody, and a biotinylated goat-anti-mouse IgG, as secondary antibody. Furthermore, Western blot analysis of seminoma extracts was carried out. RESULTS: Intense P450 arom immunoreactivity was observed in the seminoma cells and Western blot analysis confirmed the immunodetection. A strong immunostaining was also detected in cells of intratubular germ cell neoplasia (IGCN), adjacent to seminoma. CONCLUSION: The present study demonstrated, for the first time in human, aromatase expression in neoplastic cells of seminoma suggesting a relation between local estrogen biosynthesis and germ cell tumorigenesis. The P450 arom immunolocalization in the cells of IGCN, representing the common precursor of most germ cell tumors, seems to support these findings.

Adult↗
PubMed1976

Influence of brain and behavior on the immune system.

It has been shown experimentally that psychosocial processes influence the susceptibility to some infections, to some neoplastic processes, and to some aspects of humoral and cell-mediated immune responses. These psychosocial effects may be related to hypothalamic activity. Reviewing the mechanisms that may be involved in the role of the hypothalamus in immune responses indicates that there is no single mediating factor. Various processes may participate, including the autonomic nervous system and neuroendocrine activity. The research reviewed has been limited primarily to a consideration of the effect of hypothalamic lesions on humoral immune responses. There is some evidence (45, 80) indicating that hypothalamic lesions also modify cell-mediated immune responses. Further research is required to evaluate the effect of the hypothalamus on cell-mediated immunity.

Adrenal Cortex Hormones↗
PubMed1983

Computed tomographic identification of calcified optic nerve drusen.

Four cases of optic disk drusen were accurately diagnosed with orbital computed tomography (CT). The radiologist should be aware of the characteristic CT finding of discrete calcification within an otherwise normal optic disk. This benign process is easily differentiated from lesions such as calcific neoplastic processes of the posterior globe. CT identification of optic disk drusen is essential in the evaluation of visual field defects, migraine-like headaches, and pseudopapilledema.

Calcinosis↗
PubMed2004

Adenosine deaminase, xanthine oxidase, superoxide dismutase, glutathione peroxidase activities and malondialdehyde levels in the sera of patients with head and neck carcinoma.

OBJECTIVES: Clinical and epidemiological findings have provided evidence supporting a role of free radicals in the etiology of cancer. Scavengers and inhibitors of free radical processes have been demonstrated to prevent or delay the neoplastic process. PATIENTS AND METHODS: Adenosine deaminase, xanthine oxidase, superoxide dismutase, and glutathione peroxidase activities and malondialdehyde levels were measured in the sera of 35 patients with head and neck cancers and were compared to those of healthy control subjects. RESULTS: Serum adenosine deaminase activity was found to be significantly increased in the patient group (p<0.001). Compared to the control group, glutathione peroxidase and xanthine oxidase activities and malondialdehyde levels were slightly higher and serum superoxide dismutase activity was slightly lower in the patient group, with none reaching statistical significance. CONCLUSION: The results indicate that serum adenosine deaminase activity may be helpful in the diagnosis and follow-up of head and neck cancers. Further studies with a larger cohort of patients are needed to clarify the exact mechanism of adenosine deaminase elevation.

Adenosine Deaminase↗
PubMed2006

[Interleukin 2 concentration changes in the laryngeal cancer patients during the surgical treatment].

INTRODUCTION: Cytokines are molecules that regulate the process of differentiation and proliferation. They are also the mediators of immunological and inflammatory reactions. One of the cytokines that participates in immunological processes is interleukine-2 (IL-2), whose participation in neoplastic processes has been proved in many researches. It's anticancer effect is an indirect one and is connected with stimulating processes of immunologically competent cells, which are cytotoxic for cancer cells. IL-2 is produced by T-helper lymphocytes (THL), and on the basis of feedback it stimulates those lymphocytes to new cells and other cytokines, which stimulate next immunity cells or kill the cancer cells, production. The aim of the study was to evaluate the serum level concentration of IL-2 in the laryngeal cancer patients before any medical treatment and its denotation after the surgical procedure. MATERIAL AND METHODS: A group of 22 male patients with laryngeal cancer was considered for the purpose of this study. All of them were treated by surgery. In all the cases the serum concentration of IL-2 before the treatment, in the first and 30th day after therapy was evaluated. The results were compared with the group of 20 healthy volunteers. RESULTS: The mean value of IL-2 concentration in laryngeal cancer patients treated by surgery was 23.4 pg/ml before treatment, increased to 37.8 pg/ml in the 1 day and to 54.3 pg/ml 30 days after the therapy. The serum concentrations of IL-2 in the laryngeal cancer patients were lower than in the control group before the surgical treatment. These IL-2 concentrations increased significantly after the surgery and 1 month after the treatment were higher than in the healthy population. CONCLUSION: The serum concentration of IL-2 in the laryngeal cancer patients treated by surgery is lower than in the healthy control group. IL-2 increased significantly after the surgery to higher levels than in the control healthy group.

Adult↗
PubMed1979

[Clinical pathology of colonic mucosal polyps].

Of 636 polyps removed during endoscopy between 1973 and 1975 at the University Hospital, Zurich, 36 (5.5%) were of the hyperplastic and 18 (2.8%) of the juvenile type. One polyp was seen in a female patient with Peutz-Jeghers syndrome. The vast majority of the polyps (581, 91.5%) were neoplastic in origin; 70% were tubular adenomas, 16% villous adenomas, and 14% intermediate forms or tubulo-villous adenomas. On the basis of a continuous spectrum in histologic structure and similar cellular dedifferentiation, these three types of adenoma may be viewed as different forms in the development of the same neoplastic process. Hyperplastic and hamartomatous polyps are innocuous, whereas the neoplastic forms may well turn aggressive. Malignant change was observed in 5.1% of our material, particularly in villous adenomas and in polyps exceeding 1 cm in diameter. The presence or absence of invasive growth through the muscularis mucosae is of prime importance for therapy. In accordance with WHO nomenclature, the term carcinoma is used only in the presence of such infiltration. If, in addition, the tumor tissue is not well differentiated, additional segmental resection may be required. The term "focal carcinoma" is no longer in use and has been replaced by "severe focal atypia". In these cases, primary polypectomy for diagnostic purposes is also the optimal therapy, and is as effective here as in cases of benign adenoma.

Adenoma↗
PubMedDate not supplied

Oncogenic genes and human malignancy.

All vertebrates possess a series of genes which are homologs of the oncogenic genes of acute transforming retroviruses. Two lines of evidence suggest that these genes may play a role in the development of human malignancy: (1) DNA from a variety of human tumors transforms NIH 3T3 mouse fibroblasts and the transforming genes from a number of carcinomas, sarcomas, and hematological malignancies have been identified as members of a family of genes, the ras family, closely related to the oncogenic genes of the Harvey and Kirsten murine sarcoma viruses; and (2) correlations exist between the chromosomal localizations of certain oncogenes and the chromosomal breakpoints in specific translocations and deletions in certain human malignancies. In three separate hematological malignancies, alterations in more than one oncogenic gene may be involved in the neoplastic process.

Animals↗
PubMed1997

Optic nerve decompression for compressive neuropathy secondary to neoplasia.

OBJECTIVE: To evaluate the outcome of extracranial optic nerve decompression in patients with compressive optic neuropathy secondary to intracranial, paranasal sinus, or orbital neoplastic processes. DESIGN: A retrospective chart review and clinical follow-up of patients who underwent optic nerve decompression. SETTING: Tertiary care referral center. PATIENTS: During an 8-year period, 95 extracranial optic nerve decompressions were performed by one of us (M.P.J.) for optic neuropathy resulting from traumatic, inflammatory, infectious, iatrogenic, neoplastic, and idiopathic processes. Thirty patients with compressive optic neuropathy secondary to histopathologically confirmed tumors were identified. INTERVENTION: Optic nerve decompression via external ethmoidectomy approach. RESULTS: Twenty (67%) of 30 patients showed improvement in vision. Improvement in 17 of the 20 patients has been stable. Seven patients (23%) showed no improvement but there was no further worsening of vision after surgery. In 3 patients (10%) vision deteriorated following surgery. CONCLUSION: Extracranial optic nerve decompression may be considered for the preservation or improvement of vision in selected patients with compressive optic neuropathy from neoplasms.

Adult↗
PubMed2005

Benign ovarian serous tumors: a re-evaluation and proposed reclassification of serous "cystadenomas" and "cystadenofibromas".

OBJECTIVE: Serous cystadenomas and cystadenofibromas of the ovaries are currently regarded as neoplasms and are considered the most common ovarian neoplasms. The purpose of this study is to determine what proportion of benign serous tumors contain an epithelial proliferation (the hallmark of a neoplastic process in nearly all other sites) that can be considered neoplastic as opposed to reactive in nature. METHODS: An unselected series of 113 ovarian serous tumors (76 serous cystadenomas and 37 serous cystadenofibromas) were histologically evaluated. A 1-mm in diameter area of epithelial proliferation was considered potentially neoplastic. RESULTS: Eight tumors (7%) displayed at least 1 mm of epithelial proliferation (1% of serous cystadenomas and 19% of serous cystadenofibromas). CONCLUSION: The vast majority of benign serous tumors may not be bona fide epithelial neoplasms, but rather, may represent cystically dilated glandular inclusions (cystadenomas) and fibromas with epithelial inclusions (cystadenofibromas). A recently published study evaluating clonality in serous cystadenomas found that the vast majority are polyclonal and thus supports this hypothesis. These findings have important implications for the pathogenesis of ovarian cancer, for the distribution of ovarian neoplasms, and for the interpretation of molecular biological studies of ovarian tumors.

Cell Proliferation↗
PubMed1999

Fibro-osseous lesions of the central nervous system: report of four cases and literature review.

Fibro-osseous lesions, also reported as calcifying pseudoneoplasms of the neural axis, are uncommon lesions of the CNS. We report four additional cases: two extraaxial and two intraaxial, in patients ages 33, 47, 49, and 59 years at presentation. Fibro-osseous lesions involving the CNS demonstrate variable proportions of fibrous stroma, bone, palisading spindle to epithelioid to multinucleated cells in association with a highly distinctive, perhaps pathognomonic, chondromyxoid-like matrix often distributed in a nodular pattern. This histopathologically distinctive lesion can be seen in many regions of the neuraxis, often with a dural association, and most commonly along the vertebral column. It appears to be a slow-growing lesion and, with wide excision, the prognosis is excellent. The etiology remains unclear, but the preponderance of data favors a reactive rather than neoplastic process. If this putative pseudotumor is not recognized histopathologically, a neoplastic or infectious differential might result in inappropriate investigations and potentially harmful therapies.

Adult↗
PubMed1976

A case of chronic granulocytic leukemia in a dog.

A case of chronic granulocytic leukemia was diagnosed in a ten year old miniature poodle and was observed for four and one half years. Methods of diagnosis and characteristic features are described. A persistent granulocytosis with a preponderance of mature forms and the absence of a detectable underlying pyogenic process were key diagnostic features which enabled distinction of this neoplastic process from acute granylocytic leukemia and a leukemoid reaction. Other features included dysplastic granulocytes in various developmental stages, marginal anemia and hyperplastic bone marrow (myeloid elements). No blast crisis occurred. This dog was euthanatized in August 1975.

Animals↗