case_images: PMC11195025_01
case_images: Type II pleuropulmonary blastoma. Autopsy and histological findings: a. A mediastinal mass (blue arrowhead), compressing the heart with fluids accumulation into pericardium. b. Histopathological exam of the specimen - note a heterologous mass with epithelial islands (black arrows), cartilage (orange 5 points star), cysts (green points stars). (HE, x40); c. The mesenchymal component comprised undifferentiated primitive tissue (orange star) and blastoid structures (green star) while cyst is lined by a cuboidal epithelium with varies degrees of atypia (blue arrow) (HE, x100); d. Complete developed cartilaginous island inside the tumoral mass (HE, x100). e. Heterologous rhabdoid cells are not unusually findings in PPB (HE, x400); f. The presence of focally atypia, as presented here in a focus of stromal cells, mandatory for a PPB diagnosis (HE, x400).
case_images: acc-11-02-10286-g001.jpg
case_images: PMC11195025_01_acc-11-02-10286-g001.jpg
case_images: f1
case_images: The fetus, weighing 360 grams and measuring 28 cm (Figure 1a). The mass measured 3.5 x 2.3 x 1.6 cm and displayed an encapsulated appearance (Figure 1b). The mediastinal mass displayed an inhomogeneous composition with cystic areas and solid formations consisting of epithelial components and immature mesenchymal tissue (Figure 1b). The cystic areas were variably lined with atypical cuboidal ciliated epithelium (Figure 1c). The mesenchymal component comprised undifferentiated primitive tissue (Figure 1c orange star) and blastoid structures (Figure 1c green star). The presence of normal histological tissue such as cartilage (Figure 1d), pathological like rhabdoid structures (Figure 1e), or some bizarre multinucleate cells with nuclear atypia were observed (Figure 1f).
case_images: Type II pleuropulmonary blastoma. Immunohistochemistry findings: a. CK7 positive in the remaining epithelium lining the collapsed cyst (top center) and in the conglomerate immature epithelial components (bottom center) (IHC, anti-CK7 mAb, x100); b. Desmin positive in rhabdoid neoplastic components (IHC, anti-Desmin mAb, x200); c. Intense nuclear staining with p53 antibody in majority of epithelial cells is indicative for malignant transformation (IHC, anti-p53 mAb, x100); d. Beta catenin nuclear positivity in cluster of cells and epithelium lining cystic component (IHC, anti-beta catenin mAb, x100)
case_images: acc-11-02-10286-g002.jpg
case_images: PMC11195025_01_acc-11-02-10286-g002.jpg
case_images: f2
case_images: Immunohistochemical analysis revealed positive staining for AE1/AE3, CK7 (Figure 2a), and TTF1 in the epithelial component, as well as desmin (Figure 2b) and myogenin in rhabdoid structures. Noteworthy our findings include aberrant localization of p53 (Figure 2c) and beta-catenin (Figure 2d).