Doppler US with perfusion software and contrast medium injection in the early evaluation of isolated limb perfusion of limb sarcomas: prospective study of 49 cases

Background: The aim of this study was to prospectively evaluate the use of Doppler ultrasonography with perfusion software and contrast agent injection (DUPC) during isolated limb perfusion (ILP) with high-dose chemotherapy and TNF-alpha(biochemotherapy) in patients with locally advanced extremity soft tissue sarcoma (STS). Patients and methods: Fifty-two patients were prospectively included in this monocentric imaging trial. Three were excluded because the study was incomplete in two patients and one tumour did not exhibit any contrast uptake. DUPC was performed before ILP and on days 1, 7, 15, 30 and 60 after ILP. A total of 292 DUPC were performed on 55 target lesions in 49 evaluable patients. The percentage of contrast uptake was evaluated at each tumour site by two radiologists. The criterion tested was a decrease of more than 50% in intra-tumour contrast uptake compared to the pre-ILP examination. Results were compared with both MRI and histological analysis after resection of residual disease. Results: According to MRI and the histological analysis, 25 (51%) patients were good responders (no difference between the four treatment arms) with tumour necrosis exceeding 90% and 24 (49%) were poor responders. As of day +1, the accuracy of DUPC in predicting tumour response was 82% (18/25 good responders and 22/24 poor responders) increasing to 91% at day +7, 95% at day +15 and 96% at day +30. At day +15, DUPC was predictive of a good response in 100% of the cases. Conclusion: DUPC is a simple technique, allowing early prediction of tumour response after ILP. A new treatment planning scheme can be proposed based on the results of this study.