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K Peris

Publications and source records attributed to K Peris.

43 records · Page 3Linked to original sources
PubMed1991

Proto-oncogene expression in dermal naevi and melanomas.

Overexpression of proto-oncogenes (c-onc) may be involved in the initiation and progression of human neoplasia. We investigated the mRNA expression of the proto-oncogenes c-myc, c-fos, c-neu (erb B-2) and Ha-ras in 12 cutaneous melanocytic lesions (four dermal naevi, seven melanomas; one cutaneous metastatis of melanoma) and in normal skin (five cases) by Northern blot analysis; mRNA expression levels were quantified by densitometry of the specific bands. The expression of c-myc mRNA was higher in naevi than in melanomas, whereas c-fos mRNA expression was significantly higher in melanomas than in naevi. No significant differences were detected in the c-neu and Ha-ras mRNA levels in naevi and melanomas. The expression of c-neu mRNA was higher in normal skin than in the melanocytic lesions examined. Our results suggest that enhanced c-myc and c-fos expression may play an important role in the growth of melanocytic naevi and melanomas. The overexpression of c-fos may be involved in the progression of a particular subset of melanoma. Activation of Ha-ras and the c-neu gene, as determined by mRNA overexpression, does not seem to play a significant role in the progression of cutaneous pigmented lesions. Expression of c-neu may have an important function in the proliferation and/or differentiation of normal cells of the epidermis.

Genes, fos↗
PubMed1991

Expression of c-myc in cutaneous lymphomas and pseudolymphomas.

The expression of the proto-oncogene c-myc was studied in tumorous skin lesions of (cutaneous) lymphoproliferative diseases (3 cases of pseudolymphoma, 8 cases of non-Hodgkin lymphoma and 1 case of lymph node involvement in mycosis fungoides) in a total of 12 patients. c-myc mRNA levels were quantified by Northern blot analysis followed by densitometric evaluation of the specific bands. Higher levels of c-myc mRNA expression were observed in lymphomas as compared with pseudolymphomas (p greater than 0.05). No significant differences in c-myc mRNA values were detected between B and T cell pseudolymphomas. Our results suggest that c-myc mRNA overexpression is associated with malignant lymphomas of the skin. We conclude that the measurement of c-myc mRNA levels may contribute to further characterize cutaneous lymphoproliferative diseases.

Blotting, Northern↗
PubMed1991

Angiosarcoma of the face and scalp. A case report with complete spontaneous regression.

A wide, hemorrhagic lesion occurred on the face and scalp of a 75-year-old woman who had no history of previous trauma to the region. Histology showed features consistent with a diagnosis of angiosarcoma. Clinical and radiologic investigations failed to show any sign of internal involvement. The lesion completely regressed without any therapy within a few months from onset, and the patient is alive and free of disease 36 months after the first observation. Repeated clinicoradiologic investigations failed again to prove visceral diffusion of the tumor. Spontaneous regression of an angiosarcoma is an exceptional event, and only one similar case has been reported in the literature.

Aged↗
PubMed1990

[Immunophenotype of lymphocytic infiltrate in mycosis fungoides at the plaque stage and at the tumor stage. A comparative study].

An immunohistochemical study of 18 cases of mycosis fungoides (8 cases in tumor stage, 10 in plaque stage) is reported. Seven immunohistochemical parameters were set to evaluate the immunophenotype of the lymphocytes int he two stages of the disease. The results showed loss of differentiation and marked activation of the neoplastic lymphocytes with the progression of the disease from plaque to tumor stage.

Antibodies, Monoclonal↗
PubMed1989

[Analysis of point mutations of Ha-ras gene in basaliomas and spinaliomas usiang the polymerase chain reaction (PCR) technic].

Polymerase chain reaction is a recently developed procedure to detect point mutations in human genomic DNA. The sensitivity and specificity of this technique which requires a very little amount of DNA, have allowed the large scale screening of tumors. The Authors report the detection of point mutations of Ha-ras gene at codon 12 in 12 basal cell carcinomas and 10 cutaneous squamous cell carcinomas by the use of polymerase chain reaction in paraffin-embedded tissue sections. The gene alteration was identified in 2 basaliomas whereas no squamous cell carcinoma showed point mutations. These results suggest that point mutations of Ha-ras gene do not represent a general activating mechanism in cutaneous epitheliomas.

Basal Cell Carcinoma↗
PubMedDate not supplied

Histopathologic interobserver agreement on the diagnosis of melanocytic skin lesions with equivocal dermoscopic features: a pilot study.

AIMS AND BACKGROUND: Dermoscopy (dermatoscopy, skin surface microscopy, epiluminescence microscopy) has been increasingly employed in recent years for the preoperative detection of cutaneous melanoma, and dermatoscopic features of pigmented skin lesions have been previously defined using histopathology (HP) as the "key to the code". The aim of the present study was to evaluate the interobserver agreement on the HP diagnosis in a series of epiluminescence microscopy equivocal melanocytic skin lesions. STUDY DESIGN: Ten melanocytic skin lesions were selected on the basis of diagnostic disagreement of at least 2 out of 9 epiluminescence microscopy observers. The histologic specimens from the 10 lesions were examined by 9 HP observers. The agreement of the HP diagnoses was calculated by means of Fleiss' k statistics. RESULTS: The overall HP agreement was less than excellent (k = 0.5). When considering the prevailing epiluminescence microscopic and HP diagnoses, 2 cases were shown to be epiluminescence microscopy false-negative melanomas. Virtually no agreement was found among epiluminescence microscopy observers in 4 cases (40%) or among HP observers in 3 cases (30%). However, only one pigmented skin lesion remained unclassifiable on epiluminescence microscopy as well as HP. CONCLUSIONS: When at least 2 epiluminescence microscopy experts disagree in the evaluation of a given melanocytic skin lesion, even HP consultations may give equivocal results. The need to establish more reliable epiluminescence microscopic and HP criteria by performing an improved and meticulous clinicopathologic correlation, e.g. by using telecommunication via Internet, is emphasized.

Adult↗