2002 CTOS Annual Meeting Oral Presentations — Medical Oncology

FLUORODEOXYGLUCOSE UPTAKE IN ADULT SOFT TISSUE SARCOMA PREDICTS RISK OF RECURRENCE AFTER CHEMOTHERAPY
[Abstract ID: 31]

Category: Medical Oncology

Presentation: Oral

Authors: Scott M Schuetze¹, Brian P Rubin¹, Cheryl Vernon¹, James D Bruckner¹, Ernest U Conrad III¹, Janet F Eary¹

Author Institutions: ¹University of Washington, Seattle, Washington, United States

Presenter: Scott M Schuetze
sschuetz@fhcrc.org

Correspondent: Scott M Schuetze
sschuetz@fhcrc.org
Seattle Washington United States 98109
Ph: 206 288-2052
Fax: 206 288-2042

Objectives: Patients with localized, high-grade soft tissue sarcomas (STS) are at significant risk of developing metastasis. Chemotherapy may reduce the risk of relapse; however, not all patients benefit from treatment. High-grade STS metabolize fluorodeoxyglucose (FDG) to a greater extent than normal tissue which can be quantified by positron emission tomography (PET). We sought to determine whether the change in metabolic activity of STS in response to chemotherapy could serve as a surrogate measure for chemosensitivity and correlate with risk of disease recurrence.

Methods: FDG-PET was performed prior to doxorubicin-based chemotherapy and prior to surgery. Patients were followed for a minimum of 2 years for recurrence of disease and death. Patient outcomes were analyzed by Kaplan-Meier analyses stratified by change in FDG uptake, tumor grade, tumor size and pathologic response.

Results: Thirty-eight patients with localized, high-grade STS were retrospectively studied. Seventeen patients remain free of tumor with a median follow-up of 3 years. Patients with a greater than 40% decrement in the maximum FDG uptake in STS in response to chemotherapy had a significantly lower risk of relapse and improved survival. Risk of relapse did not correlate with tumor grade, size or pathologic response to therapy.

Conclusions: A change in the metabolism of FDG in response to chemotherapy may serve as a surrogate measure of chemotherapy sensitivity in high-grade soft tissue sarcomas. Patients with a large decrement in FDG uptake in response to doxorubicin-based therapy have a lower risk of disease recurrence and improved survival.