Delayed diagnosis and tumor stage in Ewing's sarcoma.

The relationship between tumor stage and time to diagnosis was investigated in a consecutive series of 618 patients with Ewing's sarcoma. This tumor is diagnosed late, with a mean interval between initial symptoms and biopsy of 4 months. The interval between the clinical onset and the final diagnosis was not associated with tumor stage. On the contrary, patients with metastatic Ewing's sarcoma were generally diagnosed at an earlier time than patients with localized disease, possibly reflecting inherent biological differences in aggressiveness among sub-groups of Ewing's sarcoma.