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A Spatz

Publications and source records attributed to A Spatz.

65 records · Page 4Linked to original sources
PubMed1992

[Oncogenes and tumor-suppressor genes].

Tumors arise as a result of a chain of genetic alterations that impair normal cell functions and lead to invasion and development of metastases. These genetic alterations may result either in qualitative or quantitative changes in genes that play a key role in normal cell function, called proto-oncogenes, or in inactivation of genes that normally inhibit cell growth, called tumor suppressor genes. Whatever the mechanism involved, responses of the cell to changes in the environment become inappropriate. This paper successively reviews the various categories of proto-oncogenes, the mechanisms by which proto-oncogenes can be activated, and several examples of tumor suppressor genes. The various genetic factors involved in cell transformation probably act together to create a network of molecular interactions that results in tumor progression.

ErbB Receptors↗
PubMed1990

[Rapid diagnosis of cytomegalovirus hepatitis after liver transplantation. Use of monoclonal antibody E13 directed against an early viral antigen].

Liver biopsies obtained from 10 liver transplant patients for whom a cytomegalovirus (CMV) hepatitis was suspected on the basis of clinical and biological abnormalities have been studied by an immunohistological method using the monoclonal antibody E-13 directed against an early viral antigen. Biopsies were performed between the 30th and the 77th day after transplantation. In 7 of the 10 cases, CMV hepatitis was diagnosed by histological examination because of the association of lobular cytolysis, inflammatory infiltrate with neutrophils and intranuclear inclusions. Ten cases were positive with the E-13 antibody including the 3 cases in which histological examination was not conclusive. In all cases, positive results gave a nuclear staining pattern in hepatocytes (63%) or endothelial cells (40%), independently of the presence of inclusions. Rapid diagnosis of CMV hepatitis is of significant importance since anti-viral drugs, such as DHPG (Ganciclovir), are now efficient. The immunohistochemical method with E-13 could permit easy and rapid detection of CMV in liver specimens.

Adolescent↗
PubMedDate not supplied

[Melanoma of the penis: 6 cases].

BACKGROUND: Melanomas of the penis are rare tumors of poor prognosis. METHODS: Six cases of melanoma of the penis, followed between 1975 and 2002, were retrospectively reviewed. We collected the data on epidemiological, clinical and pathologic factors, treatment and follow-up. RESULTS: The mean age was 44 years. The time to diagnosis was 2 years. Two patients had general predisposing factors for melanoma, and 3 patients local predisposing factors. Two patients had partial penectomy and 4 patients had conservative excision. One patient had local recurrence, and another had metastatic course resulting in death. Five patients out of 6 were alive and disease free at time of the study, with a 24 month follow-up. DISCUSSION: The identified risk factors for the development of penile melanoma are melanosis and pre-existing nevus. Delayed diagnosis explains the usually bad prognosis. Classical surgical treatment used to be radical, but recently, conservative surgery has been proposed. For an early diagnosis, genital melanosis requires surgical excision, when technically feasible, and any atypical lesion of the penis should be submitted to a biopsy.

Adolescent↗
PubMedDate not supplied

Value of high-frequency US for preoperative assessment of skin tumors.

The purpose of this study was to evaluate the accuracy of high-frequency ultrasound (US) in the preoperative assessment of skin tumors. A US scanner with a 20-MHz probe was used to visualize and evaluate 70 skin lesions (38 clinically suspected melanomas and 32 suspected basilar cell carcinomas [BCCs]) before surgical resection. A US morphologic study and a Doppler analysis of vascularity were performed for each tumor. Of the 70 tumors, 62 were clearly visualized, including 19 melanomas, 12 nonmalignant nevi, and 31 BCCs. Most lesions were hypoechoic. In 13 of 19 proved melanomas, the difference between the histologic and US measurements was equal to or less than 0.2 mm. Vessels were visualized in melanomas with thicknesses greater than 3 mm. All BCCs were visualized, and in 29% of cases of BCC, tumor size at US was greater than that at clinical examination. High-frequency, high-resolution US is a simple, reliable, noninvasive method for accurate preoperative assessment of skin tumor dimensions. This technique allows surgical planning to be adapted and reexcision to be avoided. However, its role is limited in the differential diagnosis of malignant and benign skin lesions.

Basal Cell Carcinoma↗
PubMedDate not supplied

Reproducibility of histopathologic diagnosis and classification of non-melanocytic skin cancer: a panel exercise in the framework of the multicenter southern European study HELIOS.

AIMS AND BACKGROUND: The reproducibility of histologic diagnoses, and in particular of the distinction between basal and squamous cell forms, has been evaluated in the framework of a multicenter case-control study (in Italy, France, Spain and Switzerland) aimed to assess the causes of non-melanocytic skin cancers. METHODS: A panel composed of 10 pathologists from the collaborating centers was appointed. A total of 1,774 slides of routine diagnoses were blindly reviewed by a second panelist; discordant diagnoses underwent a third examination. Controversial and interesting cases were discussed during general sessions. RESULTS: The results showed a high degree of concordance (99.5%), with a Cohen's kappa of 0.85 (95% CI, 0.77-0.94) in the assessment of malignancy of lesions. The concordance in the distinction between large morphologic groups, basal cell carcinoma and squamous cell carcinoma was also high (Cohen's kappa = 0.85; 95% CI, 0.82-0.89). The assessment of histologic subtypes, degree of invasion and differentiation showed a lower degree of concordance, presumably as a consequence of a weaker consistency in the relevant classifications. CONCLUSIONS: The reproducibility study has therefore validated the epidemiologic study and in particular allowed to correct some misclassifications that could have lessened the analysis of the case-control study. In general, because of its characteristics (number of pathologists and variety of their origins, the large number of cases examined, blind examination of histologic slides), the conclusions of the study may show a certain degree of generalization, at least with regard to the countries represented. Routine histologic diagnoses of cutaneous carcinoma showed a high degree of reliability with reference to the assessment of malignancy and the distinction between basal and squamous cell carcinoma morphotypes.

Adult↗