Solid Malignancies of Childhood
PP 9 Wilms’ tumor
Image 0033 Kidney almost entirely replaced by fleshy tan tumor with areas of hemorrhage and necrosis. The tumor is circumscribed by a pseudocapsule. A small rim of residual kidney with attached ureter can be seen at the right.
PP 10 Low power magnification of a triphasic Wilms' tumor
Image 0034 demonstrates pale staining stroma alternating with darkly staining blastema. Within the blastema, epithelial differentiation in the form of irregular ribbons and tubules is seen.
PP 11 Retroperitoneal neuroblastoma
Image 0035 Probably arising in the adrenal, but without visible adrenal tissue in the specimen. The tumor appears lobulated and deep red to grey tan in color with extensive calcification giving it a speckled yellow appearance.
PP 12 High magnification of an undifferentiated neuroblastoma
Image 0036 Tumor cells are small and hyperchromatic without visible cytoplasm. Pale, pink-staining neurofibrillary stroma is visible in some areas, identifying the tumor as neuroblastoma. Homer-Wright pseudorosettes are not present in this picture.
PP 13 Botryoid rhabdomyosarcoma arising in the bile duct
Image 0037 The grape-like ("botryoid") clumps of tumor are characteristic of rhabdomyosarcoma arising within any hollow structure. These tumors are associated with embryonal histology.
PP 14
Image 0038 The microscopic features of alveolar rhabdomyosarcoma are readily apparent in this micrograph. Undifferentiated tumor cells line fibrovascular septae, with the central cells "falling out" to give the alveolar appearance. At top and right, cells with abundant eosinophilic cytoplasm and a central or somewhat eccentric nucleus demonstrate rhabdomyoblastic differentiation.