Use of positron emission tomography in localized extremity soft tissue sarcoma treated with neoadjuvant chemotherapy

Abstract

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. Cancer 2005. © 2004 American Cancer Society.

Impact of Dynamic 18F-FDG PET on the Early Prediction of Therapy Outcome in Patients with High-Risk Soft-Tissue Sarcomas After Neoadjuvant Chemotherapy: A Feasibility Study

“…The use of SUV for the quantification of 18 F-FDG studies is a robust parameter that reflects tumor viability and has a prognostic value. Nonresponders demonstrated higher mean SUVs in the baseline study (5.5 vs. 3.9) as shown in the present study (Supplemental Table 1a) and as reported in the literature (8,12,15). Therefore, baseline 18 F-FDG uptake may have a prognostic value.…”

“…The literature data concerning the change in 18 F-FDG uptake after chemotherapy and long-term therapy outcome are divergent. Schuetze et al demonstrated in patients with localized extremity STSs treated with NAC that less than 40% decrease in SUVmax was a bad prognostic criterion, because these patients were at high risk of systemic disease recurrence estimated to be 90% at 4 y from the initial diagnosis (15). The main problem of the use of percentage change of 18 F-FDG metabolism is that sensitivity and specificity depend on the cutoff level used for discrimination, and dependence on cutoff level is furthermore dependent on the tumor histology and therapy used.…”

Dual-time point 18FDG-PET/CT imaging may be useful in assessing local recurrent disease in high grade bone and soft tissue sarcoma

“…During the initial workup of sarcomas, MRT provides better description and definition of the local extent of the tumor. PET/CT has been found to be useful in prognostication, grading and assessing response to chemotherapy [2,6,7]. SUVmax has been shown to correlate with tumor grade and progression [8,9].…”

PET Imaging for Treatment Response in Cancer

“…In a series of patients who had localized extremity soft tissue sarcomas treated with adriamycin-based neo-adjuvant chemotherapy followed by resection, the change in FDG uptake from baseline after therapy was highly correlated with survival. 50 In a mixed group of bone and soft tissue sarcoma patients, the reduction in tumor FDG uptake correlated with percent tumor necrosis in the resected tumors. 51 …”