P3.01-014 Differential Gene Expression of Lung Adenocarcinoma Histology Subtypes According to the IASLC/ATS/ERS Classification

Abstract

which were not available. Post-amputation b-hCG levels were high and she had been treated with multimodality chemotherapy for choriocarcinoma. She had good response to chemotherapy initially, however became resistant later on. Review of lung biopsy in the light of the past history along with extensive literature review led to the final diagnosis of metastatic trophoblastic tumor to lung. Figure 1-The lung biopsy shows an invasive tumor (A) (H&E, 10Â); composed of polygonal cells with moderate amount of eosinophilic cytoplasm, round to oval nuclei and inconspicuous nucleoli (B) (H&E, 20Â). Hyaline eosinophilic material is seen amid tumor cells with mitotic activity (C) (H&E, 20Â). These tumor cells show strong nuclear immunopositivity for p40 in approximately half of the tumor cells (D) (IHC, 20Â). Conclusion: Hence, awareness that p40 immunopositivity can be seen in trophoblastic tumors is essential to avoid misdiagnosis, especially in sites like lung where squamous cell carcinoma is common.