PMC6098234_01
Axial ultra-low-dose CT images with mediastinal window (A) and lung window (B) reveal a round and smoothly marginated low-attenuation nodule located anterior to the left hilum (asterisks). The obtuse angle formed between the nodule and the adjacent lung parenchyma (arrows) suggests a mediastinal lesion.
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The ultra-low-dose CT scan revealed a round and smoothly marginated low-attenuation nodule (maximum diameter, 25 mm) located anterior to the left hilum in the phrenic nerve region (Fig. 1).
Axial dynamic contrast-enhanced CT images obtained before contrast medium injection (A), at 30 seconds (B), 1 minute (C) and 3 minutes (D) after contrast medium injection show that the nodule has predominant fluid attenuation with rim enhancement and thick hypervascularized septa (arrowheads in B). Note that the lesion is closely abutted to the superior pulmonary vein (asterisk in B).
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The dynamic contrast-enhanced CT scan revealed that the nodule had predominant fluid attenuation (approximately 10 Hounsfield Units) with rim enhancement and thick hypervascularized septa and was closely abutted to the superior pulmonary vein (Fig. 2).
Axial PET (A) and fused PET/CT (B) images show no pathological FDG uptake within the nodule.
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No pathological fluorodeoxyglucose (FDG) uptake was observed within the lesion (Fig. 3) or in the rest of the body.
Histological hematoxylin and eosin images of the pulmonary hamartoma at actual size (A), 20x (B) and 40x (C) showing the predominant myxomatous component and clefts lined by respiratory epithelium. The blue circle and red square in A indicate the area of magnification displayed in B and C, respectively. The magnification in B shows a cleft lined by compressed respiratory epithelium with increased vascularity. Note the minimal area of cartilage (arrows) within the nodule. The magnification in C depicts the predominant myxomatous component with a central pseudocystic appearance.
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