PET response signals increased survival in soft-tissue sarcoma
Patients with soft-tissue sarcoma (STS) who demonstrate an early pathologic response on positron emission tomography (PET) after the initial cycle of neoadjuvant chemotherapy survive longer than patients showing no such response, according to recent study findings.
Neoadjuvant chemotherapy is associated with considerable toxicity and limited survival benefits in persons with STS. For this study, the researchers sought to learn whether 2[18F]fluoro-2-deoxy-D-glucose (18F-FDG)-PET/computed tomographic (CT) imaging could predict survival in STS patients after an initial cycle of neoadjuvant therapy.
A total of 39 STS patients underwent 18F-FDG-PET/CT imaging to measure tumor metabolism (how much glucose was being taken up by the tumor) before and after the first round of chemotherapy. Persons whose tumors had a reduction in metabolic activity of 25% or more were later determined to have significantly higher survival rates than persons with a tumor-activity reduction of less than 25%. As the investigators noted in Clinical Care Research (2012;18:2024-2031), 7 of 15 early PET nonresponders died during follow-up, compared with only 4 of 24 early PET responders.
The PET response can help clinicians determine quickly whether a person with STS is receiving appropriate chemotherapy.