ALPP and testicular germ cell tumor: Immunohistochemical analysis of biopsy specimens typically demonstrates positive staining for AFP, Glypican-3, SALL4, and placental alkaline phosphatase (PLAP) [9], which is crucial for differentiating PMYST from other anterior mediastinal malignancies, including thymoma, lymphoma, and other germ cell tumors [3,10].