case_images: PMC4399517_01
case_images: Microscopic findings in the antemortem specimens.. Notes: Hematoxylin and eosin staining for computed tomography-guided lung tumor biopsy specimens (A) and visceral pleura specimens using video-assisted thoracoscopic biopsy (B) revealed adenocarcinoma. Immunohistochemical analyses showed that tumor cells were positive for TTF-1 (C) and NAPSA (D), and negative for CK 5/6 (E), CgA (F) and SYP (G).. Abbreviations: CgA, chromogranin; CK 5/6, cytokeratin 5/6; NAPSA, Napsin A; TTF-1, thyroid transcription factor-1.
case_images: ott-8-783Fig1.jpg
case_images: PMC4399517_01_ott-8-783Fig1.jpg
case_images: f1-ott-8-783
case_images: She had been diagnosed with T2bN1M1a adenocarcinoma (stage IV with visceral pleural nodules) harboring an EGFR exon 19 deletion by computed tomography (CT)-guided lung tumor biopsy (biopsy was performed twice) and by visceral pleural nodule biopsy using video-assisted thoracoscopy (biopsy was performed once) (Figure 1).
case_images: Chest computed tomography (CT) images.. Notes: CT performed before gefitinib treatment showed a mass shadow in the right S10 (red circle) and right hilar lymphadenopathy (A and B). One month after gefitinib therapy, these shadows were reduced (C and D). However, only a few months after gefitinib therapy (on the present admission), chest CT showed atelectasis in the right middle and lower lobes (E and F).
case_images: ott-8-783Fig2.jpg
case_images: PMC4399517_01_ott-8-783Fig2.jpg
case_images: f2-ott-8-783
case_images: Chest CT showed that the tumor and right hilar lymphadenopathy were reduced 1 month after gefitinib therapy was initiated (the longest dimension of the tumor decreased by 62.1% after gefitinib therapy) (Figure 2A-D). However, only a few months after gefitinib therapy (on the present admission), CT showed atelectasis in the right middle and lower lobes (Figure 2E and F).
case_images: Antemortem and postmortem specimens analysis.. Notes: Antemortem (A-D) and postmortem specimens (E-H) analysis. Hematoxylin and eosin staining (A and B). Double immunohistochemical staining of CDH1 (in blue) and VIM (in brown) (B and F). Immunohistochemical staining of HGF (C and G). MET gene translocation (fluorescence in situ hybridization, red signal: MET gene probe, green signal: Centromere enumeration probe 7) (D and H).. Abbreviations: CDH1, E-cadherin; HGF, hepatocyte growth factor; VIM, vimentin.
case_images: ott-8-783Fig3.jpg
case_images: PMC4399517_01_ott-8-783Fig3.jpg
case_images: f3-ott-8-783
case_images: Surprisingly, microscopic examination revealed a diffuse proliferation of atypical giant cells in the primary and metastatic lesions, but no adenocarcinomatous components such as those seen in the antemortem specimens were observed (Figure 3). Using the antemortem and postmortem specimens, we also evaluated EGFR mutations, PIK3CA mutations, and MET gene amplification (Table 1 and Figure 3).