Role of Napsin A and Survivin Immunohistochemical Expression in Bronchogenic Adenocarcinoma

Background: Lung cancer, being the leading cause of cancer deaths with most patients diagnosed at a late stage, represents a major burden in developing countries especially with both air pollution and tobacco use increasing. With the evolution of new, successful therapies that target lung adenocarcinoma, it became of utmost importance to diagnose lung adenocarcinoma. Despite considering TTF-1 as the predominant marker for identifying lung adenocarcinoma but it has limited sensitivity and specificity, which means that its expression decreases in relation to the degree of tumor differentiation. Aim of work: this study intended to evaluate the use of Napsin A in lung adenocarcinoma, and observe if it can withstand along the different lines of tumor differentiation and Survivin as a marker of poor prognosis. Materials and Methods: Forty paraffin blocks of bronchogenic carcinoma were collected and studied immunohistochemically against Napsin A and Survivin. Results: There was a statistically significant relation between Napsin A reactivity and tumor grade as 72% of grade II as well as all cases of grade I were strongly positive compared to none of grade III cases. Another statistically significant relation between Survivin reactivity and tumor grade was observed as all grades I and II cases showed labeling index <10%, while all grade III cases showed labeling index >10%. Conclusion: Napsin A is a good prognostic marker while Survivin stands as a poor one for lung adenocarcinoma with a statistically inverse relation between the two, which means that Napsin A can’t be used as a marker for diagnosing poorly differentiated tumors.