Tumors Of Epidermal Origin Research Articles

A Retrospective Histopathological Study of Non-Melanocytic Skin Tumors

Background: Three most frequent primary skin cancers are basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and malignant melanoma. Together SCC and BCC are referred to as non-melanoma skin cancers (NMSC). NMSCs comprise of 1-2% of all diagnosed cancers in India in contrast to one-third in whites. SCC represents 30%-65% of skin cancers in blacks and Indians, whereas BCC contributes to 65%-75% of skin cancers in whites.
 Methods: Total 100 cases of Non-melanocytic skin Tumors were studied retrospectively by paraffin section and H&E staining.
 
 Result: A histopathological study of 100 cases of non-melanocytic skin tumors was carried out in Department of pathology, B.J. Medical College, Ahmedabad over a period of two years from January 2015 to December 2017. Out of 100 cases, histopathologically 57 were diagnosed as benign and 43 as malignant lesions. Among 57 benign lesions, 31 (55%) were tumors of epidermal in origin, 10 (17%) were epidermal appendageal in origin and 16 (28%) were soft tissue in origin. Out of 43 malignant cases, 37 (87%) were tumors of epidermal origin, 04 (09%) were lymphoma, 01 (2%) was leiomyosarcoma and 01 (2%) was metastatic carcinoma.
 
 Conclusion: Unlike in the western countries, in India Squamous cell carcinoma is the commonest histologic variety. Diagnosis of skin tumor can be done by correlating clinical features, gross and histologic appearances. In some cases, rare entities and problems of differential diagnosis may be solved with the help of immunohistochemical and/or electron microscopic studies.

Histopathological Study of Epithelial, Melanocytic And Adnexal Tumors Of Skin- A Retrospective Study In A Tertiary Care Centre

Background and objectives: To classify and identify various skin tumors and study their variations according to age and sex. The most common predisposing factors being fair skin, sun exposure, chemical exposure, HPV infection in the setting of immunosuppression.
 Methods: This was an observational study carried out in the Department of Pathology at private Medical College of coastal Andhra from July 2018 to June 2020.
 Result: The present study included histopathological study of 71 cases of tumors of skin and its adnexae over a period of two years. Out of the 71 tumors, 43 were diagnosed as benign and 28 as malignant tumors of skin constituting 61% and 39% respectively. The ratio of benign to malignant tumors was 1:0.63. Among the 43 benign tumors 20 (46.5%) were tumors of skin appendages, 15 (34.9%) were tumors of epidermis, 8 (18.6%) were of melanocytic origin. Among the 28 malignant tumors 25 (89.3%) were tumors of epidermis, 2 (7.1%) were melanocytic tumors and 1 (3.6%) was tumor of skin appendages. Among the malignant epidermal tumors squamous cell carcinoma was the most common constituting 42.9% (12 cases).
 Conclusion: The present study concludes that benign tumors are most common when compared to malignant tumors of skin. Among the malignant tumors, Squamous cell carcinoma falls as the most common variety of skin followed by Basal cell carcinoma and verrucous carcinoma. Among the benign tumors, tumors of epidermal origin are most frequent followed by tumors of sweat gland and adnexal-hair follicle origin.

Post-transcriptional Up-regulation of ADAM17 upon Epidermal Growth Factor Receptor Activation and in Breast Tumors

ADAM17 is a transmembrane metalloprotease involved in the proteolytic release of the extracellular domain of many cell surface molecules, a process known as ectodomain shedding. Despite its likely participation in tumor progression and its current consideration as a therapeutic target, very little is known about the regulation of the expression of ADAM17. Here we show that long term treatment with epidermal growth factor (EGF) leads to a marked increase in the levels of ADAM17. EGF receptor activation does not affect the levels of the mRNA that encodes for, or the rate of synthesis of, ADAM17 but increases its half-life. The effect of EGF is biologically relevant because it increases the shedding of several substrates of ADAM17, including the desmosomal cadherin Dsg-2. Analysis of protein and mRNA levels in mammary tumor samples shows that in vivo the levels of ADAM17 can also be controlled post-transcriptionally. Finally, we show that both the shed extracellular domains of Dsg-2 and ADAM17 are frequently expressed in tumors, further supporting the participation of the metalloprotease in malignant progression.

Characterization of keratin peptide in sebaceous carcinomas.

The keratins are a family of water-insoluble proteins (MW 40-68 kDa) that form the intermediate filaments of almost all epithelial cells. There are 20 subunits (K 1 ~ K20) [15, 19] that are differentially expressed in different epithelia at various stages of differentiation and development [3, 4, 15]. To date, numerous studies on keratin expression have been reported in skin tumors of epidermal origin, such as squamous cell carcinoma (SCC) [8, 11, 18, 28] and basal cell carcinoma (BCC) [6, 8, 11, 16] and there have been only a few reports of studies on keratin expression in skin adnexal tumors [14, 21, 30]. Moreover, no studies on keratin analysis of sebaceous carcinoma (SC) have yet been reported. In the present paper, we analyzed keratins in two sebaceous carcinoma specimens using histological, gel electrophoretic, and immunoblot techniques. The tumor tissues used in this study were obtained from surgical specimens from the following two cases of SC: case 1, an 86-year-old woman with a 1-year history of a left preauricular 60 x 70 x 40 mm ulcerated domeshaped tumor; case 2, a 71-year-old man with a 2-year history of a right thigh 25 x25 x 10mm tumor. The specimens were cut into several sections. One section was fixed in 10% formalin for a routine histological study and the other sections were used for keratin extraction. The diagnoses of SC were confirmed by examination of hematoxylin and eosin (HE) stained paraffin-embedded sections using conventional histological criteria [12]. Histological examination of the tumor in case 1 revealed that the tumor lesions in the dermis formed irregular lobular proliferations composed of germinative basaloid cells and atypical sebaceous cells with foamy cytoplasm. Numerous mitoses and keratinized material were observed. Peripheral palisading was never marked and no

Epidermal Nevi and Tumors of Epidermal Origin

Benign lesions of the epithelial surface, tumors of melanocytic derivation, appendicular tumors, and cancerous lesions of the epidermis are discussed with emphasis on their cosmetic effect, possible association with systemic disease, and potential for malignant degeneration.

Antigenic alterations in tumors of epidermal origin

One hundred tumors of epidermal origin were studied by means of indirect immunofluorescence technique with sera from patients with proven pemphigus and bullous pemphigoid. We found that in tumors of epidermal origin, there was a loss of antigenicity of the intercellular substance and basement membrane; this was minimal for benign tumors, greater for premalignant tumors, and very clear for malignant tumors. We also found a gross correlation between the histologically proven malignancy of squamous cell carcinoma and the grade of antigenic loss; both for the intercellular substances and for the basement membrane antigens. However, this did not yeild definite results in the group with basal cell carcinoma. With regard, especially, to the intercellular substance antigen, it seemed to be completely independent of histologic type of basal cell carcinoma. We found that the duration of the epidermal tumor did not correlate with the percentage of intercellular substance and basement membrane antigenic loss. This suggested that the antigenic loss was an early feature of neoplastic behavior. The deeper parts of the malignant tumors in the dermis showed a lower percentage of antigenicity for both antigens.