Proton-beam, intensity-modulated, and/or intraoperative electron radiation therapy combined with aggressive anterior surgical resection for retroperitoneal sarcomas.
BACKGROUND
We sought to reduce local recurrence for retroperitoneal sarcomas by using a coordinated strategy of advanced radiation techniques and aggressive en-bloc surgical resection.


METHODS
Proton-beam radiation therapy (PBRT) and/or intensity-modulated radiation therapy (IMRT) were delivered to improve tumor target coverage and spare selected adjacent organs. Surgical resection of tumor and adjacent organs was performed to obtain a disease-free anterior margin. Intraoperative electron radiation therapy (IOERT) was delivered to any close posterior margin.


RESULTS
Twenty patients had primary tumors and eight had recurrent tumors. Tumors were large (median size 9.75 cm), primarily liposarcomas and leiomyosarcomas (71%), and were mostly of intermediate or high grade (81%). PBRT and/or IMRT were delivered to all patients, preferably preoperatively (75%), to a median dose of 50 Gy. Surgical resection included up to five adjacent organs, most commonly the colon (n = 7) and kidney (n = 7). Margins were positive for disease, usually posteriorly, in 15 patients (54%). IOERT was delivered to the posterior margin in 12 patients (43%) to a median dose of 11 Gy. Surgical complications occurred in eight patients (28.6%), and radiation-related complications occurred in four patients (14%). After a median follow-up of 33 months, only two patients (10%) with primary disease experienced local recurrence, while three patients (37.5%) with recurrent disease experienced local recurrence.


CONCLUSIONS
Aggressive resection of retroperitoneal sarcomas can achieve a disease-negative anterior margin. PBRT and/or IMRT with IOERT may possibly deliver sufficient radiation dose to the posterior margin to control microscopic residual disease. This strategy may minimize radiation-related morbidity and reduce local recurrence, especially in patients with primary disease.
Yoon
Sam S
SS
Division of Surgical Oncology, Department of Surgery, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA. sam.yoon@uphs.upenn.edu
Chen
Yen-Lin
YL
Kirsch
David G
DG
Maduekwe
Ugwuji N
UN
Rosenberg
Andrew E
AE
Nielsen
G Petur
GP
Sahani
Dushyant V
DV
Choy
Edwin
E
Harmon
David C
DC
DeLaney
Thomas F
TF
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007432:Intraoperative Period; D007890:Leiomyosarcoma / Q000532:radiotherapy / Q000601:surgery; D008080:Liposarcoma / Q000532:radiotherapy / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000473:pathology / Q000517:prevention & control / Q000532:radiotherapy* / Q000601:surgery*; D009367:Neoplasm Staging; D011446:Prospective Studies; D061766:Proton Therapy; D011859:Radiography; D011879:Radiotherapy Dosage; D018714:Radiotherapy, Adjuvant; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods; D012186:Retroperitoneal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D012509:Sarcoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D016896:Treatment Outcome; D011522:Protons
D011522:Protons