Intraoperative radiotherapy electron boost followed by moderate doses of external beam radiotherapy in resected soft-tissue sarcoma of the extremities.
OBJECTIVE
To analyze the patterns of failure and the toxicity profile of intraoperative electron beam radiotherapy (IOERT) after resection of soft tissue sarcomas of the extremities (STS).


METHODS
Forty-five patients with extremity STS were treated with IOERT and moderate-dose postoperative radiotherapy (45-50 Gy). Twenty-six patients were treated for primary disease (PD) and 19 patients for an isolated recurrence (ILR). Tumor size was >5 cm (maximum diameter) in 36 patients (80%), and high-grade histology in PD patients was present in 14 patients (54%). In nine patients, IOERT was used alone, due to previous irradiation or patient refusal. Chemotherapy (neoadjuvant and/or adjuvant) was mainly given to high-grade tumors.


RESULTS
Nine patients relapsed in the extremity (20%), and 12 patients in distant sites (28%). Actuarial local control at 5 years was 88% for patients with negative/close margins and 57% for patients presenting positive margins (P=0.04). Five patients (11%) developed neuropathy associated with the treatment. Extremity preservation was achieved in 40 patients (88%). With a median follow-up of 93 months (range: 27-143 months) for the patients at risk, 25 patients remain alive (a 7-year actuarial survival rate of 75% for PD and 47% for ILR; P=0.01).


CONCLUSIONS
IOERT combined with moderate doses of external beam irradiation yields high local control and extremity preservation rates in resected extremity STS. Peripheral nerves in the IOERT field are dose-limiting structures requiring a dose compromise in the IOERT component to avoid severe neurological damage.
Azinovic
Ignacio
I
Department of Oncology, Radiation Oncology Division, Clínica Universitaria, School of Medicine, University of Navarre, Av. Pio XII, 36, 31008 Pamplona, Spain.
Martinez Monge
Rafael
R
Javier Aristu
Jose
J
Salgado
Esteban
E
Villafranca
Elena
E
Fernandez Hidalgo
Oscar
O
Amillo
Santiago
S
San Julian
Miguel
M
Villas
Carlos
C
Manuel Aramendía
Jose
J
Calvo
Felipe A
FA
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D015331:Cohort Studies; D003131:Combined Modality Therapy; D005121:Extremities / Q000528:radiation effects / Q000601:surgery; D005260:Female; D006801:Humans; D007432:Intraoperative Period / Q000009:adverse effects / Q000379:methods; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000532:radiotherapy*; D010525:Peripheral Nerves / Q000528:radiation effects; D011879:Radiotherapy Dosage; D011882:Radiotherapy, High-Energy / Q000009:adverse effects* / Q000379:methods*; D012509:Sarcoma / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D012983:Soft Tissue Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D016019:Survival Analysis; D017211:Treatment Failure