Prognostic significance of 18F-FDG uptake in primary osteosarcoma after but not before chemotherapy: a possible association with autocrine motility factor/phosphoglucose isomerase expression

Abstract

Response to neoadjuvant chemotherapy is a significant prognostic factor for osteosarcoma (OS). 18-F-fluorodeoxy-D: -glucose (FDG) positron emission tomography (PET) is a noninvasive imaging modality that correlates with histological grading in musculoskeletal sarcomas. To determine the prognostic value of FDG PET in patients receiving chemotherapy, 13 patients were evaluated by FDG-PET, and followed for more than 4 years. FDG PET standardized uptake values before (SUV1) and after (SUV2) chemotherapy were analyzed and correlated with the expression of metastasis-related glycolytic enzyme, autocrine motility factor (AMF)/phosphoglucose isomerase (PGI) by immunohistochemical examination in surgically excised tumors. Although mean SUV1 for OS patients with metastatic lesions were similar to those in the completely disease-free (CDF) group (6.5 vs. 6.6, respectively, P = 0.975), mean SUV2 for OS with metastatic lesions were significantly higher than those in the CDF group (5.1 vs. 2.5, respectively, P = 0.0445). Interestingly, immunohistochemical analysis using anti-AMF/PGI antibody revealed that SUV2 correlated significantly with the AMF/PGI staining titers (P = 0.0303), while no correlation between SUV1 and the AMF/PGI staining titers existed (P = 0.964). The present study suggests that FDG PET after chemotherapy may provide information for AMF/PGI-related metastatic potentiality of residual tumors located out side of the area surgically resected afterward, and then lead to a useful prediction of the patients' prognosis.

18F-FDG PET/CT as an Indicator of Progression-Free and Overall Survival in Osteosarcoma

“…Many of our findings, such as the association between tumor necrosis and outcome (2,4,9-11) and the association of worse survival with high metabolic activity in the chemotherapy-naïve tumor (17) and with high metabolic activity after chemotherapy (17), all confirm the conclusions of prior studies that 18 F-FDG PET accurately reflects response of osteosarcoma to chemotherapy. Despite the small number of deaths and relatively short follow-up, our study results are similar to a recently published study with follow-up periods of more than 4 y that showed that survival is associated with SUV max after chemotherapy (21).…”

“…Few published studies assess the utility of 18 F-FDG PET in the evaluation of the response of osteosarcoma to neoadjuvant chemotherapy (16)(17)(18)(19)(20)(21). Many of our findings, such as the association between tumor necrosis and outcome (2,4,9-11) and the association of worse survival with high metabolic activity in the chemotherapy-naïve tumor (17) and with high metabolic activity after chemotherapy (17), all confirm the conclusions of prior studies that 18 F-FDG PET accurately reflects response of osteosarcoma to chemotherapy.…”

“…Imaging currently plays a major role in assessing response to chemotherapy and may include radiography or MRI or CT of the primary tumor (12) and a bone scan (15). A few studies have shown that evaluation with 18 F-FDG PET is a predictor of outcome and of tumor necrosis (16)(17)(18)(19)(20)(21).…”

Imaging in Sarcoma

“…Implications for limb salvage surgery were described because such complex tumor resection procedures might not be considered in nonresponders (52). Others have recently shown similar results for 18 F-FDG imaging in osteosarcoma (53,54).…”

Positron emission tomography for the evaluation of soft-tissue sarcomas and bone sarcomas

“…Sato et al [6] evaluated a series of 13 patients by measuring the sarcoma SUV max before and after the neoadjuvant chemotherapy and correlated them with the expression of metastasis-related glycolytic enzyme and autocrine motility factor/phosphoglucose isomerase by immuno-histochemical examination in surgically excised tumours. The follow-up was 4 years.…”