USMLE (United States Medical Licensing Examination) Step 1 Practice Exam

Which tumor is characterized by neural crest cell origin and childhood onset?

1. Primary B-cell lymphoma

2. Primary hyperparathyroidism

3. Neuroblastoma

4. Resp Alkylosis + Ca2+ Homeostasis

The correct answer is: Neuroblastoma

Neuroblastoma is indeed characterized by its origin from neural crest cells and is the most common tumor found in infants and young children. This type of cancer typically arises from the sympathetic nervous system, most frequently in the adrenal glands or along the sympathetic nerve chain. Key features of neuroblastoma include its ability to present with various clinical manifestations such as abdominal masses and symptoms related to catecholamine release. The age of onset is crucial; neuroblastoma commonly occurs in children under the age of 5, which distinguishes it from other tumors. Other options do not relate to neural crest cell origin or childhood presentation. For instance, primary B-cell lymphoma typically affects older populations and does not stem from neural crest cells. Primary hyperparathyroidism is predominantly seen in adults and results from parathyroid gland issues rather than tumors originating from neural crest cells. The last choice, "Resp Alkylosis + Ca2+ Homeostasis," refers to a metabolic condition rather than a specific tumor type. Therefore, neuroblastoma is the most appropriate answer as it fits both the criteria of neural crest cell origin and childhood onset.