Objective: To demonstrate that expectant observation of young infants with small adrenal masses would result in excellent event-free and overall survival.
Background: Neuroblastoma is the most common malignant tumor in infants, and in young infants, 90% of neuroblastomas are located in the adrenal gland. Although surgical resection is standard therapy, multiple observations suggest that expectant observation could be a safe alternative for infants younger than 6 months who have small adrenal masses.
Methods: A prospective study of infants younger than 6 months with small adrenal masses and no evidence of spreading beyond the primary tumor was performed at participating Children's Oncology Group institutions. Parents could choose observation or immediate surgical resection. Serial abdominal sonograms and urinary vanillylmandelic acid and homovanillic acid measurements were performed during a 90-week interval. Infants experiencing a 50% increase in the volume of the mass, urine catecholamine values, or an increase in the homovanillic acid to vanillylmandelic acid ratio greater than 2, were referred for surgical resection.
Results: Eighty-seven eligible patients were enrolled: 83 elected observation and 4 chose immediate surgery. Sixteen observational patients ultimately had surgery; 8 had International Neuroblastoma Staging System stage 1 neuroblastoma, 2 had higher staged neuroblastoma (2B and 4S), 2 had low-grade adrenocortical neoplasm, 2 had adrenal hemorrhage, and 2 had extralobar pulmonary sequestration. The 2 patients with adrenocortical tumors were resected because of a more than 50% increase in tumor volume. The 3-year event-free survival for a neuroblastoma event was 97.7 ± 2.2% within the entire cohort of patients (n = 87). The 3-year overall survival was 100%, with a median follow-up of 3.2 years. Eighty-one percent of patients on the observation arm were spared resection.
Conclusions: Expectant observation of infants younger than 6 months with small adrenal masses led to excellent event-free survival and overall survival while avoiding surgical intervention in a large majority of the patients.
To determine the safety of expectant observation for young infants with small adrenal masses, patients were monitored with serial abdominal sonograms and urinary catecholamine measurements. Surgical resection was reserved for patients with evidence of persistent tumor growth. Using this algorithm, the vast majority of patients were spared resection with excellent survival.
*Departments of Surgery and Pediatrics, Texas Children's Hospital and Baylor College of Medicine, Houston
†Department of Pediatrics
‡Department of Radiology
§Department of Surgery, Children's Hospital Boston, Dana-Farber/Children's Hospital Cancer Center, and Harvard Medical School, Boston, MA
‖Children's Oncology Group Statistics and Data Center, Arcadia, CA
¶Department of Biostatistics, University of Florida, Gainesville
#Department of Surgery, University of Michigan, Ann Arbor
**Department of Pediatrics, University of Illinois, Chicago
††Department of Pediatrics, Children's Hospital of Philadelphia and University of Pennsylvania, Philadelphia
‡‡Department of Pediatrics, University of Chicago, Chicago, IL.
Reprints: Jed G. Nuchtern, MD, Division of Pediatric Surgery, Baylor College of Medicine, 6701 Fannin, Ste 1210, Houston, TX 77030. E-mail: firstname.lastname@example.org.
Disclosure: Supported by grants from the National Institutes of Health (NIH-NCI, UO1 CA098543, U10 CA98413, and U10 CA98543). The authors declare no conflicts of interest.