Ewing sarcoma/primitive neuroectodermal tumor of the chest wall: impact of initial versus delayed resection on tumor margins, survival, and use of radiation therapy

Abstract

Objective: To establish outcome and optimal timing of local control for patients with nonmetastatic Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) of the chest wall.

Methods: Patients < or =30 years of age with ES/PNET of the chest wall were entered in 2 consecutive protocols. Therapy included multiagent chemotherapy; local control was achieved by resection, radiotherapy, or both. We compared completeness of resection and disease-free survival in patients undergoing initial surgical resection versus those treated with neoadjuvant chemotherapy followed by resection, radiotherapy, or both. Patients with a positive surgical margin received radiotherapy.

Results: Ninety-eight (11.3%) of 869 patients had primary tumors of the chest wall. Median follow-up was 3.47 years and 5-year event-free survival was 56% for the chest wall lesions. Ten of 20 (50%) initial resections resulted in negative margins compared with 41 of 53 (77%) negative margins with delayed resections after chemotherapy (P = 0.043). Event-free survival did not differ by timing of surgery (P = 0.69) or type of local control (P = 0.17). Initial chemotherapy decreased the percentage of patients needing radiation therapy. Seventeen of 24 patients (70.8%) with initial surgery received radiotherapy compared with 34 of 71 patients (47.9%) who started with chemotherapy (P = 0.061). If a delayed operation was performed, excluding those patients who received only radiotherapy for local control, only 25 of 62 patients needed radiotherapy (40.3%; P = 0.016).

Conclusion: The likelihood of complete tumor resection with a negative microscopic margin and consequent avoidance of external beam radiation and its potential complications is increased with neoadjuvant chemotherapy and delayed resection of chest wall ES/PNET.

FIGURE 1. Kaplan-Meier estimate of event-free survival for patients according to site of primary tumor: ribs (n = 98), humerus or femur (n = 188), pelvis (n = 159), and all other sites (n = 424). No difference was seen between the rib, pelvis and humerus/femur cohorts (P = 0.26), but a clear difference existed between the “other” lesions when compared with rib (P < 0.01), pelvis (P < 0.01), and humerus/femur (P = 0.02) cohorts.

FIGURE 2. Kaplan-Meier estimate of event-free survival for patients shown according to whether they had primary resection or post chemotherapy resection (P = 0.69).

FIGURE 3. Kaplan-Meier estimate of event-free survival for patients shown by method of local control: surgery and radiotherapy, radiotherapy alone, and surgery alone (P = 0.17).

FIGURE 4. Kaplan-Meier estimate of event-free survival by method of local control (surgery alone or surgery and radiotherapy) (P = 0.97) for all patients who had complete surgical resection with pathologic margins negative for tumor.