Osteosarcoma of the pelvis: experience of the Cooperative Osteosarcoma Study Group.
OBJECTIVE
To define patients and tumor characteristics as well as therapy results, patients with pelvic osteosarcoma who were registered in the Cooperative Osteosarcoma Study Group (COSS) were analyzed.


METHODS
Sixty-seven patients with a high-grade pelvic osteosarcoma were eligible for this analysis. Fifteen patients had primary metastases. All patients received chemotherapy according to COSS protocols. Thirty-eight patients underwent limb-sparing surgery, 12 patients underwent hemipelvectomy, and 17 patients did not undergo definitive surgery. Eleven patients received irradiation to the primary tumor site: four postoperatively and seven as the only form of local therapy.


RESULTS
Local failure occurred in 47 of all 67 patients (70%) and in 31 of 50 patients (62%) who underwent definitive surgery. Five-year overall survival (OS) and progression-free survival rates were 27% and 19%, respectively. Large tumor size (P =.0137), primary metastases (P =.0001), and no or intralesional surgery (P <.0001) were poor prognostic factors. In 30 patients with no or intralesional surgery, 11 patients with radiotherapy had better OS than 19 patients without radiotherapy (P =.0033). Among the variables, primary metastasis, large tumor, no or intralesional surgery, no radiotherapy, existence of primary metastasis (relative risk [RR] = 3.456; P =.0009), surgical margin (intralesional or no surgical excision; RR = 5.619; P <.0001), and no radiotherapy (RR = 4.196; P =.0059) were independent poor prognostic factors.


CONCLUSIONS
An operative approach with wide or marginal margins improves local control and OS. If the surgical margin is intralesional or excision is impossible, additional radiotherapy has a positive influence on prognosis.
Ozaki
Toshifumi
T
Department of Orthopaedic Surgery, Westfälische Wilhelms-University, Münster, Germany. tozaki@md.okayama-u.ac.jp
Flege
Silke
S
Kevric
Matthias
M
Lindner
Norbert
N
Maas
Rainer
R
Delling
Günter
G
Schwarz
Rudolf
R
von Hochstetter
Arthur R
AR
Salzer-Kuntschik
Mechthild
M
Berdel
Wolfgang E
WE
Jürgens
Heribert
H
Exner
G Ulrich
GU
Reichardt
Peter
P
Mayer-Steinacker
Regine
R
Ewerbeck
Volker
V
Kotz
Rainer
R
Winkelmann
Winfried
W
Bielack
Stefan S
SS
D000293:Adolescent; D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001859:Bone Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D020360:Neoadjuvant Therapy; D012516:Osteosarcoma / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D010384:Pelvic Bones; D011379:Prognosis; D011446:Prospective Studies; D015996:Survival Rate; D017211:Treatment Failure; D016896:Treatment Outcome