2.3. Pathological findings of the extirpated specimen
Hematoxylin-eosin staining revealed <50% stroma of Schwann
cells and a low mitosis karyorrhexis-index (MKI) (Fig. 2D), and
immunohistochemical staining showed positivity for VIP (Fig. 2E). The
definitive pathological diagnosis according to the international
neuroblastoma pathology classification of the Shimada system [8] was
neuroblastoma, differentiating subtype with a low MKI, favorable
histology, MYCN not amplified.