IS Case 411: Neuroblastoma, metastatic to bone marrow

Sam McCabe, MD

University of Rochester


Imaging Sciences URMC 2010
Publication Date: 2010-08-27

History

Patient is a 4-year-old male with a one-week history of left leg/hip pain, weakness, mild fever, elevated ESR, presenting to evaluate for clinical suspicion of osteomyelitis.

Findings

A single posterior image of the torso from a whole body MIBG scan shows diffuse radiotracer activity in the axial and central appendicular skeleton. A large left suprarenal MIBG-avid mass is seen.

Diagnosis

Neuroblastoma, metastatic to bone marrow

Discussion

Neuroblastoma (NB) is the 3rd most common pediatric malignancy (after leukemia/lymphoma and brain tumors), accounting for 8-10% of childhood malignancies. They are the most common abdominal malignancy in children and the most common malignancy to be diagnosed in the 1st week of life. The mean age at presentation is 22 months.

NB arises from neural crest cells. They occur most commonly in the adrenal medulla but can originate anywhere along the sympathetic chain. These are aggressive tumors, often with metastasis to liver, lung and/or bone at the time of presentation.

The Evans staging system is used to determine prognosis. It is unique in that patient age plays a role in prognosis, with children <1 year old having more favorable outcomes. Stage 1 is a localized tumor (5 year survival 90%). Stage 2 has local extension beyond the organ of origin (75%). Stage 3 crosses the midline (30%). Stage 4 has distant metastasis (10%). Stage 4S is a special subgroup with near 100% long term survival: these patients are <1 year old and have metastases confined to the liver, skin and bone marrow.

Imaging features include heterogeneity reflecting internal hemorrhage and necrosis as well as calcifications on CT (in 74%). NB demonstrates MIBG as well as MDP avidity (see companion case 330). NB has a tendency to engulf and surround vessels rather than displacing them. This is in contradistinction to Wilms' Tumor, another common pediatric malignancy. NB also has a tendency to invade the spinal canal via the neural foramen, and this is an important imaging finding in the pre-operative patient. The differential diagnosis includes Wilms' Tumor, adrenal hemorrhage, and other adrenal tumors less common in childhood, including pheochromocytoma and adrenocortical carcinoma.

References

  1. Mettler FA, Guiberteau MJ. Essentials of Nuclear Imaging. 5th ed., Elsevier, Philadelphia, PA, 2006.
  2. Parisi MT, Greene MK, Dykes TM, et al. Efficacy of metaiodobenzylguanidine as a scintigraphic agent for the detection of neuroblastoma. Invest Radiol. 1992 Oct;27(10):768-73. PMID: 1399431

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