Immunohistochemical expression of cyclooxy genase- 2 [COX - 2] and vascular endothelial growth factor [VEGF] in oral: premalignant lesions and squamous cell carcinoma

Squamous cell carcinoma [SCC] represents more than 90% of all head and neck cancers. It can arise de novo or from premalignant lesions. Seventy to ninety percent of all precancerous oral lesions have the potential to develop into malignant phenotype. Early detection and identification of the molecular changes that are responsible for tumor development and progression is of paramount importance in medical and surgical intervention with improved outcome. Angiogenesis is an essential condition for the development and proliferation of malignant tumors. Cyclooxygenase [Cox-2] as well as vascular endothelial growth factor [VEGF] are two epitopes among the different pro angiogenic molecules that have been investigated in literature in relation to tumor angiogenesis. The present study aimed at delineation of the molecular expression profile of Cox-2 and VEGF factors in oral cavity premalignant dysplatic lesions and SCC and its relation to tumor development, grade and stage of the tumor. Thirty cases were studied, which included 12 tongue lesions, 3 in the cheek and 15 in the palate and mandible. The studied cases were categorized into: five oral premalignant cases [leukoplakia] and 25 cases of invasive SCC with six cases presented by metastatic cervical lymph nodes. Paraffin embedded tissues were processed and sections were immunohistochemically stained using Avidin Biotin peroxidase complex [ABC] with Cox-2 and VEGF [Ab-7] epitopes. Positive staining for Cox-2 was detected in 3 out of 5[60%] of precancerous oral lesions, but it appeared in 9 out of 25 [36%] of SCC cases. Total positivity for Cox-2 reached 40% [12 out of the 30 samples]. As regards VEGF immuno staining, positive reaction was detected in one out of 5 cases [20%] of precancerous lesions and in 12 out of 25 cases [48%] of malignant lesions. Total positive reaction for VEGF was seen in 13 out of the 30 samples examined [43%]. Expression of VEGF was almost of the same ratio in premalignant and grade I tumors [25% and 26%] respectively, but it was increased in grade II [85%] and grade III tumors [66%]. Correlation between VEGF staining and grading of the SCC showed a significant difference [p=0.018]. An interesting finding in this study, is the expression of both Cox-2 and VEGF markers in normal fibroblasts, inflammatory cells, minor salivary glandular epithelium as well as some endothelial cells. Co-expression of both Cox-2 and VEGF staining was significantly correlated [p=0.004]. The results of this study demonstrated a definite role for Cyclo-oxygenase and VEGF as two pro-angiogenic factors that proved to be existing in both oral premalignant and SCC tumors .The dysplastic epithelium nearby a tumor area or in leukoplakia lesion expressed both markers with increased ratio for Cox-2 than VEGF factor. There was a direct relationship between VEGF immunopositivity and increased SCC grade. Also,co-expression of Cox-2 and VEGF was significantly correlated. From the present study it can be concluded that, both Cox-2 and VEGF factors are expressed in oral premalignant as well as SCC lesions, but Cox-2 may have a role in early stages of tumorigenesis, while VEGF showed a clear existence in higher grades of SCC

Evaluation of CD[7] T-cell deletion marker for diagnosis of mycosis fungoides

Clinical diagnosis of mycosis fungoides [MF] in its early stages can be difficult and requires biopsy confirmation of disease. Even with histological evaluation, early-stage MF is still difficult to distinguish from various benign inflammatory dermatoses [BID]. Recent attempts to enhance the diagnostic sensitivity and specificity have mainly focused on lymphocyte Immunophenotyping and genotyping [1, 2]. Our purposes in this study were clinical and histopathologic assessment of MF patients in addition to evaluate the diagnostic value of Immunophenotyping with special reference to CD7 deletion. The study was carried on 19 MF patients and 16 cases of BID as a control group. They were subjected to full clinical examination, routine laboratory investigations and chest x- ray. Skin biopsies were obtained from all MF cases and BID control group. The paraffin embedded skin specimens were stained with hematoxylin-eosin stain [H and E] and immunostains for CD3, CD4, CD8 and CD7. According to Smoller's [3] histological criteria, the diagnosis of MF was confirmed; showing various pathologic patterns including granulomatous MF in one case. Immunophenotyping results revealed that T-cells in all MF and BID specimens were predominantly expressed CD3+, CD4+ and negatively stained by CD8. Conversely, the mean CD7+ count as a percentage of total T-cells in MF specimens [16.8%] was significantly lower than those of BID [61.7%]. The sensitivity and specificity of CD7 deletion [expressed by <50% of T-cells] for diagnosis of MF was 89.5% and 93.75% respectively. CD4/CD8 ratios greater than 2:1 and 10:1 were noticed in 73.7% and 31.3% of MF biopsies. CD4/CD8 ratios more than 10:1 were specific for MF while ratios greater than 2:1 were also found in 15.8% of BID. We can conclude that MF may manifest a variety of histological forms. Expressions of conventional T-cell markers including CD3, CD4 and CD8- do not generally distinguish benign T-cell infiltrate from MF, however, deletion of CD7 [<50%] has demonstrated considerable usefulness in the diagnosis of MF [89.5%] and was occasionally found in BID [6.25%]