ADRENAL NEUROBLASTOMA

Neuroblastoma arises from the neural crest cells. 70% arise in the abdomen, half of which arise in the adrenal gland. Neuroblastoma in situ is a benign lesion present in 1.5% of normal neonates and is presumed to either resolve spontaneously or develop into mature adrenal tissue (1). It has not been described antenatally.

ETIOLOGY / PATHOGENESIS

Etiology / Pathogenesis

ULTRASOUND

• 60-90% are in the adrenal glands (compared with only 35% of neuroblastomas in infants) (2,3).
• Usually only diagnosed in the third trimester (earlier scans on the same patients are usually normal).
• Solid.
• Cystic and anechoic (4) (50%).
• Both solid and cystic components (due to necrosis, hemorrhage and tumor involution) (5).
• Less commonly hyperechoic with calcifications.
• Usually well encapsulated and displaces the kidney inferiorly and laterally.
• Asynchronous movement between the lesion and the kidney during fetal breathing may help distinguish it from a primary renal mass.
• Usually unilateral. The right side is more frequently affected. Curtis et.al. (6) state that 90% of 31 right sided suprarenal masses were neuroblastomas. When a right sided lesion is detected after 29 weeks of gestation, the positive predictive value for neuroblastoma was 96%.
• Metastasizes to:
• Fetal liver (most common site, 25%) (7)
• Placenta (8).
• Skeleton.
• Liver.
• Neck.
• Subcutaneous tissue.
• Umbilical cord (rare).
• Fetal hydrops (several hypotheses including:
• Umbilical vein or IVC obstruction from the hepatomegaly (9).
• Hypoalbuminemia from compromised liver function.
• Mestastaic involvement of the placenta (8).
• Bone marrow infiltration resulting in anemia and cardiac failure.
• Arrhythmia due to catecholamine release resulting in cardiac failure.
• Hypersecretion of fetal aldosterone (10).
• Color doppler may demonstrate a low impedence waveform (3).

Calcified right adrenal mass
Complex cystic adrenal mass with calcified metastasis to the fetal neck

DIFFERENTIAL DIAGNOSIS

Link to Differential Diagnosis

REFERENCES

1. Beckwith JB, Perrin EV. In situ neuroblastoma: A contribution to the natural history of neural crest tumors. Am J Pathol 1963;43:1089.
2. Acharya s, Jayabose S, Kogan S et.al. Prenatally diagnosed neuroblastoma. Cancer 1997;80:304-310.
3. Goldstein I, Gomez K, Copel J. The real time and color Doppler appearance of adrenal neuroblastoma in a third trimester fetus. Obstet Gynecol 1994;83:854-856.
4. Hendry GMA. Cystic neuroblastoma of the adrenal gland - a potential source of error in ultrasonic diagnosis. Pediatr Radiol 1982;12:204.
5. Fenart D, Deville A, Donzeau M et.al. Neuroblastome retroperitoneal diagnostique in utero. A propos dun cas. J Radiol 1983;64:359-361.
6. Curtis M, Mooney D, Vaccaro T et.al. Prenatal ultrasound characterization of the suprarenal mass: distinction between suprarenal neuroblastoma and subdiaphragmatic extralobar pulmonary sequestration. J Ultrasound Med 1997;16:75-83.
7. Grosfeld J, Rescorla F, West K et.al. Neuroblastoma in the first year of life: clinical and biological factors influencing outcome. Semin Pediatr Surg 1993;2:37-46.
8. Lynn A, Parry S, Morgan M et.al. Disseminated neuroblastoma involving the placenta. Arch Pathol Lab Med 1997;121:741-744.
9. Van der Slikke J, Balk A. Hydramnios with hydrops fetalis and disseminated fetal neuroblastoma. Obstet Gynecol 1980;55:250-252.
10. Moss T, Kaplan L. Association of hydrops fetalis with congenital neuroblastoma. Am J Obstet Gynecol 1978;132:905-906.