Pulmonary Tumor Embolism and Pulmonary Tumor Thrombotic Microangiopathy Causing Rapidly Progressive Respiratory Failure: A Case Series

Figure 1.. (A) Chest radiograph revealing mild diffuse interstitial prominence and (B) CT angiography of chest revealing mild centrilobular nodular pattern and interlobular septal thickening. Abbreviation: CT, computed tomography.

Figure 2.. Pulmonary tumor thrombotic microangiopathy: (A): H&E, 10×: H&E-stained slide showing fibrocellular intimal proliferation with spindle-shaped cells (green asterisks) surrounding the pulmonary tumor emboli (blue asterisks) and completely filling the lumen of this vessel, (B) Immunostaining for CK-7, 10×: CK-7 highlights tumor cells (black arrowhead) within the lumen of muscular arteries, adjacent to intimal proliferation, (C) Immunostaining for CK-7, 10×: CK-7-positive tumor cells (blue arrowheads) present in lymphatics, and (D) Immunostaining for SMA, 10×: smooth muscle actin (SMA) highlights proliferation of smooth muscle cells within tunica intima (intimal proliferation) (black asterisks).

Figure 3.. (A) Chest radiograph at initial presentation revealing diffuse reticular opacities and tiny bilateral pleural effusions and (B) CT scan of chest without contrast revealing bilateral pleural effusions with diffuse interstitial septal thickening and scattered ground-glass opacities. Abbreviation: CT, computed tomography.

Figure 4.. Pulmonary tumor embolism: (A) H&E 10×: H&E-stained slide showing tumor cells (asterisk) within the lumen of a muscular artery, causing venous congestion without intimal proliferation, (B) Immunostaining for CK-7, 10×: CK-7 positive tumor cells (black arrowheads) in the lumen of blood vessels, and (C) Immunostaining for SMA, 10×: tumor cells (outlined in black) within the lumen of the artery without causing intimal proliferation. SMA staining is confined to the original wall of the artery and not extending into the lumen. Abbreviation: SMA, smooth muscle actin.