ABSTRACT
Context: Thyroid cancer is the most common malignant endocrine tumor. Nowadays tissue biopsy and pathological assessment are the best diagnostic modalities for thyroid lesions. Differential diagnosis between adenomas and follicular variant of papillary thyroid carcinoma (PTC) is an important issue in pathology. Aims: This study is designed to show any association between expressions of CD56 and nm23 and types of thyroid lesions (benign vs. malignant). Settings and Design: In this cross-sectional study, 78 paraffin-embedded tissue blocks of thyroid tissue from a tertiary care center were selected, and assessed by using immunohistochemistry for expressions of CD56 and nm23 genes. Materials and Methods: we studied 39 benign and 39 malignant thyroid lesions, CD56 and nm23 expressions were determined by immunohistochemical staining, and the results were used for differentiation of benign and malignant lesions of thyroid. Statistical Analysis: The obtained results were analyzed and evaluated using SPSS (Version 18). Results: CD56 was expressed in 93% of benign specimens and in only 5% of malignant types. The sensitivity and specificity of this test were 94.8% and 92.3, respectively (P = 0.001). All malignant specimens and 95% of benign specimens were positive for nm23. The sensitivity and specificity of nm23 were 100% and 5%, respectively. Conclusion: Considering high sensitivity and specificity of CD56, it is possible to apply immunohistochemistry for definite diagnosis and differentiation of benign lesions from PTC. We conclude that by using this marker, the diagnostic mistakes in pathologic diagnosis of thyroid cancer versus benign lesions like thyroid adenoma will decrease.
ABSTRACT
Context: Prostate cancer is the most common malignant tumor in men. Tumor grade is one of the most important prognostic factors of prostate cancer. P53 and Ki-67 expressions have also been considered to be prognostic factors. Aims: This study was performed to investigate the frequency of these proteins expression and compare the obtained results with Gleason's grading. Settings and Design: In this cross-sectional study, 49 paraffin blocks of prostate cancers were assessed. Tumor grade was determined according to the Gleason's criteria. Materials and Methods: Ki-67 and P53 expressions were determined by immunohistochemical staining. Statistical Analysis: The obtained results were analyzed and evaluated using Spearman's statistical test (SPSS version 15). Results: Three out of 49 (6.1%) cases were well differentiated, 21 (43%) moderately differentiated and 25 (51%) were poorly differentiated. P53 was negative in all well-differentiated cases. Ki-67 was negative in 14 cases (28%) including all well-differentiated tumors. Among moderately and poorly differentiated tumors Ki-67 was negative in eight (38%) and three (12%) of cases, respectively. A statistically significant relation was observed between the increased Ki-67 labeling index (LI) and increased Gleason's grade. Conversely, no statistically significant relation was found between P53 expression and increased Gleason's grade. Conclusions: According to the findings of this study, it seems that Ki-67 can be used as a prognostic factor for prostate cancer. On the other hand, the probable relation between P-53 and prostate cancer prognosis requires further studies.