Regressive Neuroblastoma: Widely Accepted, Underreported Histology.

Neuroblastoma accounts for approximately 8% of all pediatric cancers and up to 15% of pediatric cancer-related deaths in malignant cases; neuroblastoma is the most common malignancy in infancy. Notably, up to 50% of tumors may undergo spontaneous regression without treatment. However, detailed histological descriptions of regressed neuroblastoma remain limited in the literature. We report the histological features of a particularly illustrative case, characterized by edema, mild collagen deposition, evidence of prior hemorrhage, and calcifications. Cellularity was minimal, consisting of rare, scattered mature-appearing ganglion cells, without neuropil or neuroblastic clusters. Accurate recognition of these morphological features in surgical specimens is essential for optimal treatment planning.