Observation of untreated patients with neuroblastoma detected by mass screening: A ?wait and see? pilot study

BACKGROUND: Recent studies have indicated that mass screening for neuroblastoma detects tumors that otherwise would have regressed spontaneously without recognition. Therefore, we started an observation program for these patients to determine how frequently spontaneous regression occurs. PROCEDURE: Eighteen patients were detected by mass screening between June 1994 and December 1996. Eight of these cases matched the following criteria and entered the observation program: Stage I or II, less than 5 cm in diameter; no involvement of large vessels or organs; not difficult to resect; informed consent. If there were an increase in tumor size, an elevation of tumor markers, or evidence of metastasis, the tumor would be immediately resected. RESULTS: Five of the eight cases showed spontaneous regression. Although the remaining three tumors were resected 6-10 months after diagnosis, all patients survived without evidence of recurrence. CONCLUSIONS: At least 60% of neuroblastoma cases who entered our observation program regressed spontaneously.