Current Results With a Combined Treatment Approach to Localized Ewing’s Sarcoma

Abstract

Like many malignant tumors of childhood and adolescence, Ewing’s sarcoma should be considered a systemic disease, at least in the majority of patients. Multiple foci of neoplastic cells scattered throughout the body, mainly in the bones and lungs, are present at the time of initial diagnosis. In approximately 25% of patients metastases are clinically detectable, while in 75% they cannot be detected with the diagnostic tools currently available. In this latter group we generally detect one single bone lesion, which is considered to be the primary tumor. The concept of distant micrometastases has led clinical investigators to abandon mutilating surgical procedures and to adopt high-energy radiotherapy as the treatment of choice for the primary site [1]. Long-term results after radiation were similar to those obtained with radical surgery (cure rate: 10%–20%), while a high percentage of relapsing patients were spared a useless mutilation. However, the percentage of patients developing distant spread remained very high, and radiotherapy also failed to eradicate the primary tumor in 20%–40%. In several reported series the median disease-free survival ranged between 6 and 10 months (Fig. 1) [3, 4, 14, 16]. Once metastases were clinically evident, patients showed only a moderate and transient benefit from optimal chemotherapy, which was able to induce remission and to prolong survival but not to save a consistent number of patients.