Expression of epidermal growth factor receptor [EGFR], p53 and Ki-67 in major salivary glands tumors: a clinicopathologic and immunohistochemical study

The parotid gland is the most common site for the uncommon salivary glands tumors. However the immunohistochemical characteristics of the salivary gland tumors, regarding expression of proliferating cell antigens and oncogenes, in relation to their clinical behavior have not been fully clarified. These may provide predictive quantitative measures for the prognosis of salivary neoplasms and may assess in their management. The aim of this study was to detect the immunohistochemical expression of epidermal growth factor receptor [EGFr], ki-67 proliferating cell antigen and p53 concoprotein in major salivary glands tumors and also to study the relation between these markers expression and the clinicopathological parameters of these tumors focusing on prognostic factors and tumor differentiation. Thus twelve patients with primary tumors of their major salivary glands were included in this study. They were seven men and five women and ranged in age between 32 to 67 years [mean age=51.7 years]. All patients were treated surgically by complete excision of their masses after preoperative investigations including computed tomographic [CT] scan and fine-needle aspiration biopsy [FNAB] and followed up clinically postoperatively for a period ranging from 11 to 48 months [average =33 months]. The tumor size ranged between 15 and 55 mm [average = 31.2 mm]. The clinicopathologic features and the immunohistochemical expression of EGFr, p53 and ki-67 detected with monoclonal antibodies in these cases were analyzed. The results revealed that 6 cases [50%] showed grade-1 of differentiation while the other 3 cases [75%] were grade-II. None of these cases had cellular pleomorphism, vascular or neural invasion, recurrence, lymph modes or distant metastasis. [5 cut of 6 cases. 83.3%] and in all ALs and MECs with no significant differential expression in the various salivary gland tumors. However, p53 and ki-67 expressions were negative in almost all benign cases [PAs and Als] and positive in all MECs but with no significant difference between grade-1 and grade-II cases. Also, no significant association was found between any of these cell markers and the evaluated clinicopathologic parameters of these tumors regarding tumor location, size, aggressiveness, recurrences, lymh nodes or distant metastasis. In conclusions, there was a high prevalence of EGFr expression in primary salivary glands tumors [either benign or malignant with no significant difference]. However, p53 seems to be involved in the pathogenesis of MECs but not in Pas or Als. Also, the highly significant difference in expression of p53 and ki-67 biomarkers between the benign and the low-grade malignant tumors of the major salivary glands can help to distinguish between them, although they may have similarities in their clinicopatholoogic features

Cellular phenotypes and immunity in acquired aural cholesteatoma

Middle ear cholesteatoma is characterized by the presence or a keratinizing squamous epithelium with proliferative features and associated with marked bone destruction. Aims of this study to detect the cellular phenotypes and their immunological functional state in aquired aural cholesteatoma. So, cellular membranous expression of CD4, CD8 and HLA-DR antigens on the infilterated mononuclear cells in cholesteatoma were studied through immunohistochemical method. Nine formalin-fixed cholesteatoma specimens were obtained from patients of chronic otitis media during their ear surgery. The patients' ages ranged between 11 to 43 years [mean age=22 yrs. and SD +/- 6.5] and they involved 15 males and 12 females. All patients had dry ears with no signs of bacterial infections for at least 2 weeks preoperatively. Also, three normal skin specimens from external auditory canals of these patients were taken as a control. All tissue specimens were subjected to Hematoxylin and Eosin staining and immunohistochemical [strept-avidin-peroxidase] method staining. The results showed CD4 positive [=T- helper or inducer] lymphocytes in 24 out of 27 specimens [88.8%] with subepithelial distribution and at the periphery of lymphoid follicles in 15 cases [55.5%].While, CD 8 positive [=T-suppressor or cytotxic] lymphocytes were seen only in 6 out of 27 specimens [22.2%] with diffuse distribution pattern. On the other hand, HLA-DR expression was observed in both cholesteatoma matrix and perimatrix cellular components indicating their immunocompetent activity. Keratinocytes of cholesteatoma matrix were HLA-DR positive in 18 specimens [66.6%] while, "epidermal Langerhans" cells were positive in 12 specimens [44.4%]. In the perimatrix of all specimens, infilterated lymphocytes and macrophages were positive for HLA-DR expression. Also, [either intact or degranulated mast cells] were demonstrated in all specimens scattered in the cholesteatoma perimatrix. Active T-helper cells are directly correlated to the expression HLA-DR has a certain playing. Role in epithelial proliferation and participating in bone resorption rather than cytotoxic T-lymphocytes. Also, activated keratinocytes and Langerhans' cells and sensitized mast cells contribute to the biologic features of cholesteatoma