Chest x-ray (a) and Chest Tomosynthesis (b, c) show subsegmental atelectasis and reticular infiltration at right middle lobe.
CT Chest shows small pulmonary atelectasis at right middle lobe.
The F18-FDG-PET/CT show non-FDG avid lesion in right middle lobe, which could be a benign lesion. Pulmonary tumorlets and bronchioalveolar carcinoma may also be non-FDG avid lesion.
Figure 6a: The right middle lobe shows one accessory lobe (arrow ) superior to a minor fissue (arrow head)
Figure 6b: Serial near horizontal sections of the right middle lobe show no visible tumor nodule.
Figure 6c: The accessory lobe shows areas hemorrhage, atelectasis and clusters of dilated brochi.
Lung shows areas of hemorrhage, several blood vessels, focal fibrosis and dilated bronchi (HE x20).
Lung tissue shows three microscopic tumorlets with hemorrhage and mild focal fibrosis in the stroma. (HE x100).
One tumorlet composing of spindle, polyhedral to oval shape tumor cells with scanty to clear, vacu- olated cytoplasm and elongated to oval nuclei with speckled chromatin (HE x200).
In this fibrotic, hemorrhagic and vascularized area, there are four terminal bronchi showing neuroendo- crine cell hyperplasia (HE x100).
One tumorlet and three terminal bronchi show neuroendocrine cell hyperplasia (chromogranin A x100).
The tumorlet and foci of neuroendocrine cell hyper-plasia are also CEA positive (CEA x100).
Single, small clusters and one small nodule of chro- mogranin A positive neuroendocrine cells in the mu- cosa of one small brochus (Chromogranin A x200).
Two small nodules of neuroendocrine cells (neuro- endocrine bodies) in the bronchiolar mucosa (chro- mogranin A x200).
Lung tissue shows areas of vascular malformation and mild hemorrhage (HE x100).