Prediction of tumour necrosis fractions using metabolic and volumetric F-18-FDG PET/CT indices, after one course and at the completion of neoadjuvant chemotherapy, in children and young adults with osteosarcoma

Department of Nuclear Medicine, National Cancer Center, Goyang-si, Gyeonggi-do, Korea.
European Journal of Nuclear Medicine (Impact Factor: 5.38). 09/2011; 39(1):39-49. DOI: 10.1007/s00259-011-1936-4
Source: PubMed

ABSTRACT The utility of combined metabolic and volumetric (18)F-FDG PET/CT indices for predicting tumour necrosis fractions following neoadjuvant chemotherapy has not been extensively studied in osteosarcoma. Furthermore, little is known of the early PET/CT responses after only one chemotherapy course.
Enrolled in the study were 20 children and young adults with resectable osteosarcoma who had undergone (18)F-FDG PET/CT scans before and after neoadjuvant chemotherapy. Maximum standardized uptake value (mSUV), metabolic tumour volume (MTV), and total lesion glycolysis (TLG) were measured. From among the 20 patients, 14 were prospectively recruited and underwent an additional PET/CT scan after one chemotherapy course. Histopathological necrosis fractions were compared with the above-mentioned PET/CT indices and their ratios.
MTV at the SUV threshold of 2 g/ml was closely correlated with the magnetic resonance image volumes before therapy (r = 0.91). In the prospective cohort, five patients were classified as good responders and nine as poor responders. All the metabolic indices (mSUV and its ratio) and combined metabolic/volumetric indices (MTV, TLG, and their ratios) except the mSUV ratio determined after therapy showed significant differences between good and poor responders (P <0.05). Differences were also noted for all of these indices determined after one chemotherapy course. Furthermore, most of these indices determined after therapy as well as after one chemotherapy course had good sensitivity, specificity, positive predictive value and negative predictive value with respect to predicting histological response to chemotherapy.
In our osteosarcoma patient population, (18)F-FDG PET/CT indices (either combined metabolic/volumetric or metabolic indices) determined after neoadjuvant chemotherapy were useful in predicting tumour responses. This held true after only one chemotherapy course.

Download full-text


Available from: Jong Hyung Yoon, Aug 21, 2014
30 Reads
  • Source
    • "In a prospective study of osteosarcoma patients, MTV and TLG were significantly different after therapy between good and poor responders. These parameters had good sensitivity, specificity, positive predictive value, and negative predictive value for predicting histological responses to chemotherapy (49). In another study comparing response evaluation using volume-based PET parameters to a clinical response evaluation based on RECIST and WHO clinical criteria in patients with esophageal cancer, a decrease in MTV and TLG between baseline and post-treatment scans was the better predictor of histopathologic response and survival than a decrease in clinical response (50). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Accurate prediction of cancer prognosis before the start of treatment is important since these predictions often affect the choice of treatment. Prognosis is usually based on anatomical staging and other clinical factors. However, the conventional system is not sufficient to accurately and reliably determine prognosis. Metabolic parameters measured by (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) have the potential to provide valuable information regarding prognosis and treatment response evaluation in cancer patients. Among these parameters, volume-based PET parameters such as metabolic tumor volume and total lesion glycolysis are especially promising. However, the measurement of these parameters is significantly affected by the imaging methodology and specific image characteristics, and a standard method for these parameters has not been established. This review introduces volume-based PET parameters as potential prognostic indicators, and highlights methodological considerations for measurement, potential implications, and prospects for further studies.
    Korean journal of radiology: official journal of the Korean Radiological Society 01/2013; 14(1):1-12. DOI:10.3348/kjr.2013.14.1.1 · 1.57 Impact Factor
  • Source
    • "Most studies also assessed FDG uptake with measurement tools other than SUV, such as MTV, TLG, %ID, TBR, and their ratios. MTV has proved to be a reliable measurement of glycolytic activity within the lesion, showing a good correlation with tumour volume as measured by MRI and a much stronger association with histological response [26, 36]. TBR (obtained by drawing identical regions of interest over the tumour and the contralateral normal site) and TBR ratio (posttherapy TBR/baseline TBR) showed a high correlation with histological necrosis, in some cases much more significant than SUV [17–19]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Aim. The objective of this study is to systematically review the role of positron emission tomography (PET) and PET/computed tomography (PET/CT) with fluorine-18-fluorodeoxyglucose (FDG) in assessing the response to neoadjuvant treatment in patients with osteosarcoma (OS). Methods. A comprehensive literature search of published studies through March 2012 in PubMed/MEDLINE, Embase, and Scopus databases regarding whole-body FDG-PET and FDG-PET/CT in patients with OS was performed. Results. Twenty-two studies have investigated the role of FDG-PET and FDG-PET/CT in the evaluation of response to neoadjuvant treatment with either chemotherapy or radiation therapy in patients with OS. The main findings of these studies are presented. Conclusion. FDG-PET or PET/CT seems to be sensitive and reliable diagnostic tools in the assessment of metabolic response to treatment in patients with OS, after baseline PET evaluation has been performed in advance. However, false positive findings due to inflammation in sites of tumoral response should be considered.
    09/2012; 2012:870301. DOI:10.1155/2012/870301
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose: This study evaluated the usefulness of the maximum standardized uptake value (SUVmax) as a measure of histologic response to neoadjuvant chemotherapy in patients with extremity osteosarcoma. The correlation between [(18) F]FDG PET SUVmax values and histologic response to preoperative chemotherapy was also assessed prospectively using PET/MRI. Methods: A total of 26 consecutive patients with high-grade osteosarcoma were prospectively enrolled. All patients underwent parallel PET and MRI scans before and after neoadjuvant chemotherapy. Using the PET and MRI images and pathologic mapping, we assessed the percentage necrosis by histology at the highest metabolic activity point in the tumors. This was defined as the minimum histologic response. The predictive values of SUVmax before (SUV1) and after (SUV2) chemotherapy and the SUV change ratio were determined. Correlations were also investigated among SUV2, minimum histologic response and histologic response. Results: Histologically, 13 patients were classified as good responders and 13 as poor responders. Patients with an SUV2 of >5 showed a poor histologic response. A significant correlation was found between SUV2 and histologic response (Spearman's rho -0.642; P < 0.001), and SUV2 and histologic response were both found to be significantly correlated with minimum histologic response (Spearman's rho -0.515 and 0.911; P = 0.007 and P < 0.001, respectively). Conclusion: A SUVmax of more than 5 after neoadjuvant chemotherapy identified the majority of histologic nonresponders (sensitivity 61.3 %, PPV 88.9 %). Tumor necrosis at the point of maximum metabolic activity was found to be significantly correlated with the histologic response of entire resected specimen.
    European Journal of Nuclear Medicine 01/2013; 40(5). DOI:10.1007/s00259-013-2344-8 · 5.38 Impact Factor
Show more