Comparison of Metabolic and Anatomic Response to Chemotherapy Based on PERCIST and RECIST in Patients with Advanced Stage Non-small Cell Lung Cancer

Abstract

Background: The aim of this study was to explore the prognostic role of metabolic response to chemotherapy, determined by FDG-PET, in patients with metastatic non-small-cell lung cancer (NSCLC). Materials and Methods: Thirty patients with metastatic NSCLC were analyzed for prognostic factors related to overall survival (OS) and progression free survival (PFS). Disease evaluation was conducted with FDG-PET/CT and contrast-enhanced CT prior to and at the end of first-line chemotherapy. Response evaluation of 19 of 30 patients was also performed after 2-3 cycles of chemotherapy. Morphological and metabolic responses were assessed according to RECIST and PERCIST, respectively. Results: The median OS and PFS were 11 months and 6.2 months, respectively. At the end of first-line chemotherapy, 10 patients achieved metabolic and anatomic responses. Of the 19 patients who had an interim response analysis after 2-3 cycles of chemotherapy, 3 achieved an anatomic response, while 9 achieved a metabolic response. In univariate analyses, favorable prognostic factors for OS were number of cycles of first-line chemotherapy, and achieving a response to chemotherapy at completion of therapy according to the PERCIST and RECIST. The OS of patients with a metabolic response after 2-3 cycles of chemotherapy was also significantly extended. Anatomic response at interim analysis did not predict OS, probably due to few patients with anatomic response. In multivariate analyses, metabolic response after completion of therapy was an independent prognostic factor for OS. Conclusions: Metabolic response is at least as effective as anatomic response in predicting survival. Metabolic response may be an earlier predictive factor for treatment response and OS in NSCLC patients.

Evaluating tumor response with FDG PET: updates on PERCIST, comparison with EORTC criteria and clues to future developments

“…So far, however, there only relatively few and mostly small studies comparing RECIST and PERCIST (References: [17] [42] [43] [44] [45] [46] [47] [48] [20] [49] [50] [51] [21] [52] [53] [24] [23] [25] [54] [26] [55] [56]). A meta-analysis published in 2016 identified 6 studies including 268 patients [57].…”

Morphologic and Metabolic Comparison of Treatment Responsiveness with 18Fludeoxyglucose-Positron Emission Tomography/Computed Tomography According to Lung Cancer Type

“…Therefore, FDG uptake may be useful in the differentiation of tumor tissue, fibrosis and necrosis for which anatomical boundaries are not always distinguishable. Ordu et al (14) reported in their study that, in advanced NSCLC patients, in evaluation of response to chemotheraphy and in determination of overall survival, the metabolic response with PERCIST may be an early predictive factor in comparison with morphologic response. Our study showed that although there was no significant change in the longest total dimension, the change in post-treatment SUVmax was significant whether only the longest dimension of the primary tumor or of target lesions were taken into account.…”

Mechanism and non-mechanism based imaging biomarkers for assessing biological response to treatment in non-small cell lung cancer

“…Specificity remains low, confounded by tumour associated inflammation, while sensitivity for tumour deposits smaller than the 0.5 cm is lacking because of limited spatial resolution (especially problematic in NSCLC mediastinal nodal assessment) [10]. Repeatability coefficients of 18 FDG-PET SUVmean and SUVmax, which have been extensively studied for use in treatment response evaluation [32,34,35], are in the range 25e50% [36e39]. This is improved by measuring the SUV of the 30 most avid voxels rather than SUVmax or SUVpeak [40].…”