PMC4501525_01
Imaging findings in chest computed tomography (CT). (A) Contrast-enhanced CT showing a 74-mm irregular tumor in the right lower lobe with diaphragm invasion. (B) Plane CT showing a 111-mm tumor after 1 cycle of cisplatin plus docetaxel treatment. (C) Contrast-enhanced CT showing an 83-mm tumor after 2 cycles of carboplatin with albumin-bound paclitaxel.
gr1.jpg
PMC4501525_01_gr1.jpg
fig1
Contrast-enhanced computed tomography (CT) revealed a 74-mm irregular tumor in the right lower lobe with diaphragm invasion (Fig. 1A). First-line chemotherapy with cisplatin and docetaxel was started, but disease progression (Fig. 1B) and grade 2 creatinine elevation were observed after 1 cycle. CT taken after 2 cycles of chemotherapy demonstrated a reduction of tumor size (Fig. 1C), and FDG-PET revealed a substantial decrease of FDG accumulation in the primary tumor (Fig. 2B).
Fluorodeoxyglucose (FDG) positron-emission computed tomography findings at diagnosis and at 8 weeks after treatment initiation. (A) Marked accumulation of FDG in a marginal region of the lung tumor and low accumulation in the center of the tumor. (B) Low accumulation in the lung tumor after 2 cycles of carboplatin with albumin-bound paclitaxel. (C) Nodule-shaped accumulation in left gluteal muscles at diagnosis.
gr2.jpg
PMC4501525_01_gr2.jpg
fig2
Fluorodeoxyglucose (FDG) positron-emission CT demonstrated marked FDG accumulation in the marginal region of the lung tumor and solitary nodule-shaped accumulations in pleura, liver, and the right gluteal muscles (Fig. 2A and C).
Histopathological findings of the nodule obtained from left gluteal muscle. (A) Low-power (left) and high-power (right) images of a hematoxylin and eosin-stained section showing the tumor comprised only of spindle-shaped malignant cells with clustered necrotic regions (white arrow) and invasion to skeletal muscles (black arrow). (B) Immunohistochemical analysis showing diffuse cytokeratin AE1/AE3 (left) and vimentin (right) positivity.
gr3.jpg
PMC4501525_01_gr3.jpg
fig3
Histologically, the nodule consisted only of spindle-shaped malignant cells with invasion to skeletal muscles and clustered necrotic foci (Fig. 3A). Immunohistochemical analysis demonstrated that the tumor cells were diffusely positive for cytokeratin AE1/AE3 and vimentin (Fig. 3B), and negative for S-100, p63, synaptophysin, and thyroid transcription factor 1 (TTF-1).