A 6-month-old boy is found to have an adrenal mass on abdominal ultrasound during evaluation of a palpable abdominal mass. Urine catecholamine metabolites (VMA and HVA) are elevated. CT shows heterogeneous suprarenal mass with calcification, crossing the midline. The bone marrow aspirate shows small round blue cells arranged in pseudo-rosettes. This tumor's cell of origin and the MOST COMMON site for stage 4S (special) neuroblastoma metastasis is:
- A Neural crest cells; liver ✓
- B Adrenal cortical cells; bone
- C Sympathetic ganglion cells; lung
- D Chromaffin cells; peritoneum
Explanation
Neuroblastoma arises from neural crest-derived sympathoadrenal progenitor cells (postganglionic sympathetic neurons). Stage 4S (special) neuroblastoma, defined in infants <18 months with small primary tumor plus limited metastases, characteristically metastasizes to the liver (which can become massively enlarged — 'blueberry muffin' appearance is from skin deposits), skin, and bone marrow (<10% bone marrow involvement). Stage 4S has a favorable prognosis because many cases spontaneously regress. Bone is the hallmark of Stage 4 (non-special) disease. Lung metastases are rare in neuroblastoma.
Reference: Ghai Essential Pediatrics, 10th ed.
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Written and medically reviewed by the StethoPrep medical team.