case_images: PMC8040611_01
case_images: Computed tomography pelvis with contrast showing bilateral pelvic and groin lymphadenopathy with penile base mass and scrotal edema.
case_images: 10.1177_23247096211008717-fig1.jpg
case_images: PMC8040611_01_10.1177_23247096211008717-fig1.jpg
case_images: fig1-23247096211008717
case_images: Repeat computed tomography scan done at this time showed a mass measuring around 13 x 6.8 cm at the base of the penis with moderate bilateral pelvic and bilateral inguinal lymphadenopathy, consistent with metastatic disease (Figure 1).
case_images: (A) Shows a malignant neoplasm with multiple areas of necrosis (black arrowheads) infiltrating adipose tissue (red arrow). (B) Shows poorly differentiated, hyperchromatic tumor cells with scant cytoplasm (left) adjacent to an area of necrosis (right). (C and D) demonstrate tumor cells staining positive for synaptophysin and chromogranin, respectively, consistent with a diagnosis of high-grade neuroendocrine carcinoma.
case_images: 10.1177_23247096211008717-fig2.jpg
case_images: PMC8040611_01_10.1177_23247096211008717-fig2.jpg
case_images: fig2-23247096211008717
case_images: The tumor was composed of cohesive sheets of hyperchromatic cells with scant cytoplasm, nuclear molding, and dispersed chromatin (Figure 2A and B). Immunohistochemistry staining was positive for synaptophysin (Figure 2C), chromogranin (Figure 2D), and CAM5.2, but negative for CK7, CK20, CDX2, uroplakin II, GATA3, p63, and CK5/6.