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Immunohistochemical detection of p53 in non-malignant and malignant oral lesions associated with snuff dipping in the Sudan and Sweden.

Immunohistochemistry was used to examine the expression of p53 in pre-malignant oral lesions and oral squamous-cell carcinomas (SCCs) from Swedish and Sudanese snuff-dippers, as well as in pre-malignant oral lesions and oral SCCs from non-snuff-dippers from the Sudan, Sweden and Norway. Of the 14 SCCs from Sudanese snuff-dippers, 21% (3/14) expressed p53. Of the 14, 60 and 41 SCCs from non-snuff-dippers from the Sudan, Sweden and Norway, 64% (9/14), 65% (39/60) and 68% (28/41) expressed p53, respectively. A statistically significant difference in expression of p53 was found in SCCs from Sudanese snuff-dippers compared to those from non-snuff-dippers from all/or any of the 3 countries. None of the suspected pre-malignant oral lesions from Sudanese snuff dippers or non-snuff-dippers expressed p53. Only 2 out of the 15 oral fibro-epithelial hyperplastic lesions from Swedish snuff-dippers expressed p53. Some of the oral epithelial dysplastic lesions, as well as the carcinoma in situ lesions from Norwegian non-snuff-dippers, expressed p53, while the oral fibro-epithelial hyperplastic lesions did not. The low relative frequency of p53 expression found in oral SCCs from snuff-dippers compared to those from non-snuff-dippers might suggest differences in mechanisms of oncogenic action induced by snuff. Alternatively, the pathogenesis of malignant oral lesions from snuff-dippers may follow a p53-independent pathway. In view of the unusually high levels of the tobacco-specific nitrosamines (TSNA) found in the type of snuff used in the Sudan, investigations of p53 mutations or oncogenes are needed.

Adolescent↗

Malignant mixed tumor of the skin: malignant chondroid syringoma.

Malignant tumors of sweat gland origin are rare. Probably one of the rarest types, still poorly understood, is the so-called malignant chondroid syringoma or malignant mixed tumor of the skin. A case of malignant chondroid syringoma is presented. Ultrastructural study proves very useful for the differential diagnosis with other chondroid or chordoid tumors.

Basement Membrane↗

Malignant fibrous histiocytoma of soft tissue. Correlation between clinical variables and histologic malignancy grade.

The prognosis for malignant fibrous histiocytoma (MFH) of soft tissue is correlated to histologic malignancy grade but also has been related to tumor size, depth, and location. In a consecutive series of 61 patients with MFH we found that large, deep-seated and thigh tumors were more often highly malignant histologically. This finding suggests that the prognostic significance which has been attributed to the clinical variables may be a function of their covariation with histologic malignancy grade.

Histiocytoma, Benign Fibrous↗

Biopsy versus resection for malignant glioma.

BACKGROUND: Patients with isolated supratentorial brain tumours, presumed to be primary on imaging, have two surgical management options - biopsy or resection. Surgical opinions appear to be equally divided when considering the relative risks and benefits of these two procedures. OBJECTIVES: To estimate the clinical effectiveness of radical surgical resection compared to simple biopsy in patients with malignant glioma. SEARCH STRATEGY: Electronic database searches of COCHRANE CONTROLLED TRIALS REGISTER (including the Cochrane Cancer Network Specialised Register of Trials), MEDLINE, CANCERLIT, EMBASE, BIOSIS and SCIENCE CITATION INDEX. Hand searching the references of all identified studies; hand searching the Journal of Neuro-Oncology over the previous 10 years, including all conference abstracts; personal communication. SELECTION CRITERIA: Randomised and clinical controlled trials were included if they compared biopsy to resection, or looked at effect of extent of resection on survival, time to progression or quality of life, for malignant glioma patients of all ages. DATA COLLECTION AND ANALYSIS: Studies were to be identified, critically appraised and data extracted by the author (SEM). For dichotomous data, Peto odds ratios (OR) with 95% confidence intervals (CI) were hoped to have been estimated. Normal continuous data were to have been summated using the weighted mean difference (WMD). MAIN RESULTS: The electronic database search yielded 2100 citations. Of these, two articles were identified for possible inclusion, however both were excluded. The hand search and personal communication were similarly unproductive. No studies were included in the review and no data was synthesised. REVIEWER'S CONCLUSIONS: Given that no qualifying studies were identified and because this is an important issue, both in terms of patient risk and benefit and health economics, the author feels it important to conduct a randomised controlled trial in this subject.

Biopsy↗

Subcellular concentrations of estrone, estradiol, androstenedione and 17 beta-hydroxysteroid dehydrogenase (17-beta-OH-SDH) activity in malignant and non-malignant human breast tissues.

Total and subcellular (cytosol and nuclear) concentrations of estrone (E1), estradiol (E2), and androstenedione were determined in non-malignant (n = 61) and malignant (n = 65) human breast tissues obtained from post-menopausal women. The 17 beta-hydroxysteroid dehydrogenase (17 beta-OH-SDH) activity was determined in 800g supernatant fraction. Total estrogens, E1 and E2 levels and 17 beta-OH-SDH activity were significantly (p less than 0.005, 0.0005, 0.001, respectively) higher in malignant than in non-malignant breast tissues. We failed to observe significant changes in subcellular steroid concentrations or enzyme activity associated with patients' obesity or tumor estrogen receptor status. When the steroid levels were analyzed in relation to clinical staging of the disease, nuclear contents of estradiol were significantly higher (p less than 0.005) in Stage-IV patients than in those with less advanced disease (Stages I to III). 17 beta-OH-SDH activity was significantly (p less than 0.001) lower in patients with advanced disease than in those with relatively less advanced (Stages I to III) disease and was positively correlated with tissue concentration of androstenedione. Our present data indicate that differential intracellular metabolism of steroid hormones may have some influence on availability of estradiol at nuclear sites. In postmenopausal women, local interconversion of estrogens may provide sufficient estrogenic stimulus to enhance the growth and progression of breast tumors.

17-Hydroxysteroid Dehydrogenases↗

Immunodetection of cathepsins B and L present in and secreted from human pre-malignant and malignant colorectal tumour cell lines.

Pre-malignant and malignant human colorectal tumour epithelial cell lines both secreted precursor forms of the 2 cysteine proteinases, cathepsins B and L. The amount of proteinases secreted by these cell lines varied according to the cell density. Comparison at similar cell densities showed that the pre-malignant, adenoma-derived cell line (PC/AA) secreted as much, or more, of both cathepsin B and L precursors as did the malignant, carcinoma-derived cell line (PC/JW/FI). However, mature forms of cathepsins B and L were detected in the culture media of only the carcinoma-derived cell line, thus indicating that the invasive potential of a tumour may be related to its ability to process extracellularly the secreted precursor enzyme to a mature and consequently active enzyme, rather than to the amount of proteinase synthesized and/or secreted. Similar results were obtained using 2 other epithelium-derived tumour cell lines, HT/29 (carcinoma) and SP/AN (adenoma). Immunolocation studies showed that cathepsin B was lysosomal while cathepsin L appeared to have a distribution more consistent with a plasma membrane association. Purified human cathepsins B and L (mature form) were capable of solubilizing an isolated basement membrane matrix (bovine anterior lens capsule) in vitro, thus indicating that the secreted mature enzymes and the membrane-associated cathepsin L could potentially degrade basal laminae or sub-endothelial basement membranes in vivo.

Adenoma↗

Malignant histiocytosis in infants: surface marker analysis of malignant cells in two cases.

Two infants with malignant histiocytosis, as diagnosed by morphological and cytochemical examinations of malignant cells infiltrating pleural effusion, skin, and bone marrow, are described. Surface marker analysis of the malignant cells with monoclonal antibodies showed these cells to express markers of T-lymphocytes and HLA-DR antigen, but not those of B-lymphocytes, granulocytes, or monocytes. These immunological findings demonstrated that the neoplastic cells in malignant histiocytosis of infancy may be of T-cell origin, rather than histiocytic or monocytic origin.

Antibodies, Monoclonal↗

Primary malignancy, secondary malignancy and semimalignancy of bone tumors.

1. Bone tumors in contrast to tumors in soft tissue, show a wide variety of clinical behavior qualified by the expressions semimalignancy, low grade of malignancy, sarcomatous degeneration and primarily benign bone tumors and bone lesions. 2. The term semimalignancy is characterized by local invasive and destructive tumor growth with a tendency to recur locally but no hematogeneous spreading. Semimalignancy requires wide en-bloc resection of amputation. 3. The term low grade malignancy is used to describe a tumor of very slow growth and with very late metastasis. Low-grade malignancy requires resection with careful preservation of functional structures. 4. The term secondary malignancy means the sarcomatous degeneration of a primarily benign lesion or bone tumor. This transformation is enhanced by irradiation and probably by acceleration of the normal turnover of bone tissue. In Paget's disease sarcomatous degeneration is to be expected in 2 percent of cases and in fibrous dysplasia in 0.5 percent of cases. 5. Sarcomatous degeneration of bone infarcts is rare, but an increase is to be expected due to an increased frequency of bone infarcts caused by long-term treatment with cortisone. 6. Primary bone tumors and recurrences show the same structure and cytology. In a minority of cases the recurrences are less differentiated; in a very few cases the recurrences are more highly differentiated and have a better prognosis than the initial lesion.

Adult↗

Malignant mesenchymomas of soft tissue associated with numerous osteoclast-like giant cells mimicking the so-called giant cell variant of "malignant fibrous histiocytoma".

Three cases of malignant mesenchymoma with numerous osteoclast-like giant cells, arising in deep soft tissue, and which mimicked the so-called giant cell variant of "malignant fibrous histiocytoma" have been studied. All three neoplasms arose in adults; two patients were male and one was female. Two tumours arose in the thigh, and one in the right shoulder. Two patients died within 2 years of the primary excision while the third is alive and well at 2.5 years. Histologically, one case showed leiomyosarcoma plus liposarcoma, one leiomyosarcoma plus osteosarcoma, and one tumour consisted of liposarcoma plus osteosarcoma; all components were assessed morphologically as high-grade malignant. All three cases showed prominent osteoclast-like giant cells in the leiomyosarcomatous or osteosarcomatous areas, thereby closely mimicking the phenotype of so-called giant cell variant of "malignant fibrous histiocytoma". We discuss briefly differences in soft tissue sarcomas demonstrating this distinctive osteoclast-rich phenotype.

Adult↗

FU-3 monoclonal antibody: a specific marker for malignant fibrous histiocytoma? An analysis of 32 malignant soft tissue and bone sarcomas.

An immunohistochemical study on frozen sections was carried out on 51 malignant tumours of soft tissue and bone using the FU-3 monoclonal antibody. This antibody is claimed to be specific for malignant fibrous histiocytoma (MFH) and liposarcoma and for normal and tumour cells located in perivascular fields. The results show a lack of specificity in MFH staining: several malignant tumours such as synovial sarcoma, fibrosarcoma, rhabdomyosarcoma, osteogenic sarcoma, and including an anaplastic malignant melanoma, presented positive staining somewhat similar to that found in MFH. The value of this antibody in the differential diagnosis of MFH is doubtful. It might be useful to recognize a common pathway of terminal differentiation expressed by several pleomorphic sarcomatous neoplasms.

Antibodies, Monoclonal↗

Proliferating cell nuclear antigen in malignant and pre-malignant lesions of epithelial origin in the oral cavity and the skin: an immunohistochemical study.

Proliferating cell nuclear antigen (PCNA) is a nuclear protein synthesized in the late G1 and S phase of the cell cycle and immunohistochemical detection of the protein represents a useful marker for the proliferating fraction of cells in tissue specimens. A series of malignant and pre-malignant lesions of the oral cavity and skin were evaluated by the streptavidin biotin immunoperoxidase method for detection of this protein. Monoclonal anti-PCNA antibody (PC 10) labelled proliferating cells in all cases with varying intensity of nuclear staining. In squamous cell carcinoma (n = 48), PCNA positivity correlated with the differentiation and atypia of the tumour cells; however, in poorly differentiated tumours, the relationship between PCNA expression and proliferation was lost. Basal cell carcinoma showed an increased growth fraction in tiny epithelial nests (mean 43.8, SD 6.0, n = 20) than in neoplastic basal cells (mean 30.1, SD 6.9, n = 8). The growth fractions were significantly higher in the pre-malignant lesions (leukoplakia, mean 22.3, SD 7.7, n = 14; Bowen's disease, mean 45.2, SD 11.7, n = 12; senile keratosis, mean 41.2, SD 7.0, n = 12) than in the normal mucosa (mean 9.8, SD 4.9, n = 10), suggesting that cellular growth fractions correlate with the degree of dysplasia in pre-malignant lesions.

Antibodies, Monoclonal↗

A cohort study on second malignancies in gastrectomized patients with gastric cancer. I. Second malignancies other than cancer of the gastric remnant.

In a retrospective cohort study, a total of 235 (2.32 per cent) second malignancies were clinically observed in 10,138 patients during the average 8.8-year follow-up period. The patients had undergone gastrectomy for gastric cancer during 1960-1975, in seven different institutions. This observed number was smaller than the expected one of 340.9 (p less than 0.01). Among the 235, cancers of the gastrointestinal tract (111) were the most frequent and followed by respiratory (54) and urogenital (25) cancers. Twelve cases of malignant lymphoma and five of leukemia were also noted. With regard to adjuvant chemotherapeutic agents such as mitomycin-C (MMC), 5-fluorouracil (5FU) or its derivative Tegafur, and cyclophosphamide (EDX), no significant differences in the rate of second malignancies were obtained between the chemotherapy and non-chemotherapy groups. The occurrence rate of second malignancies tended to be higher in the Billroth II group than in the Billroth I, the significance of which is yet to be determined.

Adult↗

[The Malignant Melanoma Central Register of the German Society of Dermatology 1983-1993. Epidemiologic developments and current therapeutic management of malignant melanoma of the skin].

The Central Malignant Melanoma Registry of the German Dermatological Society was founded in 1983 and has meanwhile developed into a major continuously updated multicentre project. Up to June 1994, 19,250 reports of cutaneous melanoma had been received, from 41 departments of dermatology in the former Federal Republic of Germany, from 14 departments in the former German Democratic Republic, from 2 departments in Austria, and from 1 department in Switzerland. Analysis of the data revealed some epidemiological trends over time during the years 1983 to 1993. (1) During the last 10 years the percentage of male patients has steadily increased, from an average of 38% in the year 1983 to 46% in 1993. (2) Early diagnosis of malignant melanoma improved during the period of time investigated. The percentage of diagnoses of primary tumour alone increased between 1983 and 1993. The mean tumour thickness (Breslow) decreased in the West Germany from 1.8 mm to 1.3 mm and in East Germany from 2.5 mm to 1.7 mm. The proportion of nodular melanoma decreased correspondingly from 29% to 14% in the former Federal Republic of Germany and from 40.6% to 22.6% in the former Germany Democratic Republic. During the years 1990 and 1993, 64% of melanoma patients with the primary tumour alone were operated on in two consecutive sessions in the former Federal Republic of Germany and 34.2% of those in the former Germany Democratic Republic. During this period 73.7% of all melanoma patients were operated on under local anaesthesia. In recent years surgical operations were more often performed in two consecutive sessions, mostly under local anaesthesia and with decreasing safety margins, in keeping with the decrease in tumour thickness. The present analysis shows that the Central Malignant Melanoma Registry is an important instrument for investigating trends in clinical epidemiology and treatment of malignant melanoma in the German-speaking countries.

Adult↗

Malignant peripheral nerve sheath tumours in neurofibromatosis type 1: MRI supports the diagnosis of malignant plexiform neurofibroma.

Plexiform neurofibroma (PNF) is a typical feature of neurofibromatosis 1 (NF1). About 10% of patients with NF1 develop malignant peripheral nerve-sheath tumours (MPNST), usually arising from PNF, and this is the major cause of poor survival. A better prognosis can be achieved if the tumours are diagnosed at an early stage. Our objective was to establish MRI criteria for MPNST and to test their usefulness in detecting early malignant change in PNF. MRI was performed on 50 patients with NF1 and nerve-sheath tumours, of whom seven had atypical pain, tumour growth or neurological deficits indicative of malignancy; the other 43 were asymptomatic. On MRI all seven symptomatic patients had inhomogeneous lesions, due to necrosis and haemorrhage and patchy contrast enhancement. In one patient, the multiplicity of confluent tumours with inhomogeneous areas in addition to central lesions did not allow exclusion of malignancy. Only three of the 43 asymptomatic patients had comparable changes; the other 40 patients had tumours being of relatively homogeneous structure on T1- and T2-weighted images before and after contrast enhancement. All three asymptomatic patients with inhomogeneous lesions were shown to have MPNST.

Adolescent↗

The value of magnetic resonance imaging in the differentiation between malignant peripheral nerve-sheath tumors and non-neurogenic malignant soft-tissue tumors.

OBJECTIVE: To assess the sensitivity and specificity of MRI criteria in the differentiation between malignant peripheral nerve sheath tumors (MPNST) and non-neurogenic malignant soft-tissue tumors (MSTT). DESIGN AND PATIENTS: MRI examinations of 105 patients with pathologically proven malignant soft-tissue lesions (35 MPNST and 70 MSTT) were retrospectively reviewed, the reviewers being unaware of the pathological diagnosis. Using a standardized protocol, the tumors were evaluated for multiple parameters regarding morphology and appearance on different sequences before and after gadolinium contrast administration (location, distribution, delineation, homogeneity, size, shape, relationship to bone and neurovascular bundle, intralesional hemorrhage, necrosis, perilesional edema, lymphangitis and signal intensities). Results were compared using a chi-square or Fisher's exact test. RESULTS: MRI findings suggestive of MPNST (p<0,05) were intermuscular distribution, location on the course of a large nerve, nodular morphology, and overall non-homogeneity on T1-weighted images, T2-weighted images and T1-weighted images after gadolinium contrast injection. MRI findings in favor of MSTT were intramuscular distribution, ill-delineated appearance of more than 20% of the lesion's circumference, and presence of intralesional blood vessels, perilesional edema and lymphangitis. There is no significant difference for degree and pattern of enhancement after gadolinium contrast injection, nor for presence of bone involvement or cystic or necrotic areas. CONCLUSION: MRI provides several features that contribute to the differentiation between MPNST and non-neurogenic malignant soft-tissue tumors. MRI findings suggestive of MPNST should be helpful to pathologists in the strategy for further examination.

Chi-Square Distribution↗

Immunodetection of epithelial mucin (MUC1, MUC3) and mucin-associated glycotopes (TF, Tn, and sialosyl-Tn) in benign and malignant lesions of colonic epithelium: apolar localization corresponds to malignant transformation.

Epithelial mucins are present at the apical membranes of gastrointestinal epithelial cells or in their secretions. In this study, we examined the occurrence of peptide epitopes of the mucins MUC1 and MUC3 and of three mucin-associated glycotopes (TF, Tn, and s-Tn) in a series of colorectal tissue samples (normal colon, adenomas with different grades of dysplasia, carcinoma in situ, and invasive carcinomas). A new monoclonal antibody to a conformation-dependent peptide epitope of MUC1 was employed, which does not react with the fully glycosylated mucin as found in normal gastrointestinal mucosa. We found that adenomas acquired the ability to expose Tn, s-Tn, TF and MUC1 epitopes, and this correlated with increasing malignant potential. The secretory mucin, MUC3, revealed a different pattern: it was detectable in all sections, with maximum expression in adenomas and decrease in carcinomas. Most importantly, normal mucosa and benign lesions showed supra-nuclear and/or apical distribution of these antigens, but malignant lesions and lesions with a very high risk of malignancy revealed diffuse cytoplasmic and basolateral membrane localization. The immunohistological response to a combination of MUC1-related antibodies may assist in assessing the malignant potential and status of lesions of the colon.

Adenoma↗

Clinical implications of new studies in the treatment of benign, potentially malignant and malignant ventricular arrhythmias.

For purposes of clinical management, ventricular arrhythmias have been divided into risk categories of benign, prognostically important (potentially malignant) and malignant. Benign arrhythmias occur in the setting of structurally normal hearts and do not require therapy unless associated with debilitating symptoms. Malignant arrhythmias such as sustained ventricular tachycardia or fibrillation deserve aggressive therapy to prevent recurrence. Arrhythmias occurring in the presence of organic heart disease (often ischemic disease) are frequently asymptomatic but prognostically important as a risk factor for sudden death or cardiac arrest. The common empiric practice to treat such arrhythmias (by about 40 to 50% of cardiologists in the United States) needs to be reassessed in the face of the Cardiac Arrhythmia Suppression Trial. For malignant arrhythmias, class IA agents (procainamide and quinidine) continue to be the standard of treatment, and class IB agents (e.g., mexiletine) may be used as alternative or additive therapy. Class IC agents are used as second-line therapy, especially in the setting of ischemic heart disease. Class III therapy with amiodarone is reserved for refractory patients because of potential toxicity. Sotalol, a new class II-III agent, may become a first-line drug. For prognostically important arrhythmias, beta blockers remain the agents of choice, class IC agents are contraindicated, and class IA or IB drugs, or both, should be used conservatively (i.e., only for symptomatic arrhythmias). For symptomatic but benign arrhythmias requiring treatment, beta blockers are safe although not always effective. Class IA, IB and IC agents may then be considered. In these patients, the proarrhythmic potential of quinidine and class IC agents remains a concern.(ABSTRACT TRUNCATED AT 250 WORDS)

Amiodarone↗

Early presence of activated ('exhausted') platelets in malignant tumors (breast adenocarcinoma and malignant melanoma).

To evaluate whether or not the finding of platelet activation in patients with tumors is related to the stage of malignancy, a study of biochemical markers indicative of the presence of circulating activated ('exhausted') platelets was carried out in 95 untreated patients with breast adenocarcinoma or malignant melanoma, localized or spread to regional lymph nodes with no detectable distant metastasis. These tumors were chosen as examples of tumors which can be accurately staged for localization or spread, and as examples of mucin-secreting tumors (breast adenocarcinoma) or neuroectodermic tumors (malignant melanoma). Results were compared with those for 26 patients with benign breast disease, 23 blood donors and 50 hospital workers. The most frequent abnormalities were low levels of intraplatelet ADP and 5-hydroxytryptamine and high ATP/ADP ratios. Although these abnormalities occurred with both types of tumor, they were more frequent and marked for melanomas and breast carcinomas spread to regional lymph nodes. Our data indicate that the presence of exhausted platelets is an early finding in patients with malignant tumors.

Adenocarcinoma↗