Use of positron emission tomography in localized extremity soft tissue sarcoma treated with neoadjuvant chemotherapy.
BACKGROUND
Patients with high-grade soft tissue sarcomas are at high risk of developing local disease recurrence and metastatic disease. [F-18]-fluorodeoxy-D-glucose (FDG) positron emission tomography (PET) scans are hypothesized to detect histopathologic response to therapy and to predict risk of tumor progression in patients with various malignancies. Serial FDG-PET scans were taken to determine the correlation between FDG uptake and patient outcomes in patients receiving multimodality treatment of extremity sarcomas.


METHODS
Forty-six patients with high-grade localized sarcomas were studied. The maximum standardized uptake values (SUVmax) of tumors were measured before receipt of neoadjuvant chemotherapy and again before surgery. Resected specimens were examined for residual viable tumor. Patients were followed up at least annually for evidence of local and distant recurrence of disease and survival.


RESULTS
Patients with a baseline tumor SUVmax >/= 6 and < 40% decrease in FDG uptake were at high risk of systemic disease recurrence estimated to be 90% at 4 years from the time of initial diagnosis. Patients whose tumors had a >/= 40% decline in the SUVmax in response to chemotherapy were at a significantly lower risk of recurrent disease and death after complete resection and adjuvant radiotherapy.


CONCLUSIONS
The FDG-PET scan was found to be a useful method with which to predict the outcomes of patients with high-grade extremity soft tissue sarcomas treated with chemotherapy. The pretreatment tumor SUVmax and change in SUVmax after neoadjuvant chemotherapy independently identified patients at high risk of tumor recurrence. The FDG-PET scan showed promise as a tool to identify the patients with sarcoma who are most likely to benefit from chemotherapy.
Schuetze
Scott M
SM
Department of Medicine, University of Washington Medical Center, Seattle, Washington, USA. scotschu@med.umich.edu
Rubin
Brian P
BP
Vernon
Cheryl
C
Hawkins
Douglas S
DS
Bruckner
James D
JD
Conrad
Ernest U
EU
Eary
Janet F
JF
D000293:Adolescent; D000328:Adult; D000368:Aged; D017024:Chemotherapy, Adjuvant; D002648:Child; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D035002:Lower Extremity; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D019637:Orthopedic Procedures / Q000379:methods; D049268:Positron-Emission Tomography; D011336:Probability; D011446:Prospective Studies; D018570:Risk Assessment; D012509:Sarcoma / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000401:mortality / Q000601:surgery; D012680:Sensitivity and Specificity; D012983:Soft Tissue Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000401:mortality / Q000601:surgery; D016019:Survival Analysis; D016896:Treatment Outcome; D034941:Upper Extremity
D019788:Fluorodeoxyglucose F18