case_images: PMC10720033_01
case_images: Preoperative CT scans, (A) three-dimensional CT of the lower extremity, and (B,C) CT of the chest level. CT showed contrast deficits from the right CFA to the proximal SFA and DFA and at the popliteal artery behind the knee (arrow). There was also a contrast defect from the right pulmonary vein into the left atrium, which might be a thrombus with a direct invasion of pulmonary metastases (arrowhead). CT, computed tomography; CFA, common femoral artery; SFA, superior femoral artery; DFA, deep femoral artery.
case_images: fcvm-10-1221180-g001.jpg
case_images: PMC10720033_01_fcvm-10-1221180-g001.jpg
case_images: F1
case_images: Computed tomography showed contrast deficits from the right CFA to the proximal superior femoral artery (SFA) and deep femoral artery (DFA) and at the popliteal artery behind the knee (Figure 1A). Moreover, a contrast defect was observed from the right pulmonary vein into the left atrium, suspected to be a thrombus with direct invasion of the pulmonary metastases (Figures 1B,C).
case_images: Embolus removed intraoperatively, (A) yellow solid mass removed from the CFA, (B,C) black thrombus removed from the SFA and DFA. The CFA was found to be filled with a yellow solid mass during the incision. The black thrombi were removed from the SFA and DFA. CFA, common femoral artery; SFA, superior femoral artery; DFA, deep femoral artery.
case_images: fcvm-10-1221180-g002.jpg
case_images: PMC10720033_01_fcvm-10-1221180-g002.jpg
case_images: F2
case_images: The CFA was found to be filled with a yellow solid mass during the incision (Figure 2A), and black thrombi were removed from the SFA and DFA (Figures 2B,C).
case_images: Postoperative echocardiography, (A) left ventricular long axis view, (B) 4 chamber view.echocardiography showed no pericardial effusion (arrow). It showed a floating mass extending from the left atrial orifice of the right pulmonary vein toward the atrial septum, which was considered a potential embolic source (arrowhead).
case_images: fcvm-10-1221180-g003.jpg
case_images: PMC10720033_01_fcvm-10-1221180-g003.jpg
case_images: F3
case_images: Considering the size and location, it was the same mass observed preoperatively and thought to be a potential embolic source (Figures 3A,B).
case_images: Pathological findings: (A) HE staining, (B) CK AE1/AE3, (C) CAM5.2, (D) TTF-1. The yellow embolus removed intraoperatively shows atypical cells on HE staining (arrow). The cells are typical of epithelial carcinoma cells because CK AE 1/AE 3 and CAM 5.2 are stained positive (arrowhead). TTF-1 is stained negative, indicating undifferentiated metastasized thyroid cancer. HE, Hematoxylin and eosin; CK, cytokeratin; TTF-1, thyroid transcription factor-1.
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case_images: PMC10720033_01_fcvm-10-1221180-g004.jpg
case_images: F4
case_images: The yellow embolus removed intraoperatively had atypical cells on hematoxylin and eosin staining (Figure 4A). Additional immunostaining was performed; the cells were determined to be epithelial carcinoma cells because cytokeratin AE 1/AE 3 (Figure 4B) and CAM 5.2 (Figure 4C), which are stained positive in most epithelial cells, were stained positive. Thyroid transcription factor-1 (TTF-1), normally stained positive in thyroid cancer, was stained negative (Figure 4D); however, TTF-1 is stained negative in undifferentiated carcinoma.