PMC3738344_01
Frontal chest radiograph demonstrates multiple lung nodules. The largest lung nodule (arrow) is noted in the left lung
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PMC3738344_01_10.1258_arsr.2012.120012-fig1.jpg
ARSR-12-0012F1
A 50-year-old woman with a history of hysterectomy for uterine leiomyoma 12 years ago was examined for multiple small lung nodules, including the largest one (30 x 25 mm in size) which were incidentally discovered on chest radiographs at a private hospital (Fig. 1).
CT images show multiple well-demarcated round lung nodules of various sizes
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PMC3738344_01_10.1258_arsr.2012.120012-fig2.jpg
ARSR-12-0012F2
Unenhanced CT images showed multiple peripheral parenchymal nodules of variable sizes with smooth margins (Fig. 2).
Early 1 hour FDG-PET emission (a, c) and fused PET/CT (b, d) images show no visible FDG uptake in the multiple small lung nodules (white arrows, early SUVmax 0.5-0.8, delayed SUVmax 0.4-0.6) except the largest nodule which has faint FDG uptake (black arrows, early SUVmax 1.3, delayed SUVmax 1.2)
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PMC3738344_01_10.1258_arsr.2012.120012-fig3.jpg
ARSR-12-0012F3
Faint FDG uptake was noted in the largest nodule (Fig. 3a and b), and its early and delayed maximum standardized uptake values (SUVmaxs) were 1.3 and 1.2, respectively. In this connection, early and delayed SUVmaxs were 0.5 and 0.5 in the lung field, 1.5 and 1.4 in the thoracic muscle, and 2.4 and 1.6 in the mediastinum at the Fig. 3a tomographic level, respectively. The remaining smaller nodules <= 8 x 8 mm in diameter showed no visible uptake (early SUVmax 0.5-0.8; delayed SUVmax 0.4-0.6) (Fig. 3c and d).
(a) Microscopic examination of the lesion (HE stain, x20) showed interlacing bundles of spindle cells with elongated nuclei. (b) These cells are positive for alpha-smooth muscle actin on immunohistochemical stain (x20)
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PMC3738344_01_10.1258_arsr.2012.120012-fig4.jpg
ARSR-12-0012F4
Microscopic examinations showed an interlacing pattern by spindle cells having elongated nuclei without cellular atypia (Fig. 4a). Tumor cells were positive for alpha-smooth muscle actin (Fig. 4b) and both estrogen and progesterone receptors and negative for CD31, CD34, AE1/AE3, EMA, HMB45, and S-100 protein on immunohistochemical stains.