Prognostic Value of Preradiotherapy 18F-FDG PET/CT Volumetrics in Limited-Stage Small-Cell Lung Cancer

Abstract

Background Whether FDG PET/CT metrics predict outcome in limited-stage small cell lung cancer (LS-SCLC) has not been well established; most previous reports have only analyzed SUVmax. We investigated multiple pre-treatment PET metrics, including SUVmax, SUV mean, total lesion glycolysis (TLG), and metabolic tumor volume (MTV) in LS-SCLC patients undergoing chemoradiotherapy (CRT) and correlated them with survival and disease control outcomes. Methods All patients received platinum-based chemotherapy and a median radiation dose of 45 Gy. Kaplan-Meier and competing-risks analyses were performed to assess the prognostic value of PET metrics with respect to OS, DF, DFS, and LRF. Univariate and multivariate analyses were performed to account for the effect of other clinical factors on outcomes. Results A total of 120 patients with LS-SCLC had analyzable pre-CRT PET/CTs. The median follow up was 34 months. Median overall survival was 26.9 months. Overall survival was 53.2% at 2 years and 33.1% at 5 years. SUVmax, SUVmean, MTV, and TLG of the primary tumor were not significantly associated with OS, LRF, and DFS on univariate analysis. MTV was significantly associated with DF (p=0.024) on univariate but not multivariate analysis. Conclusions This is the largest reported series to date evaluating the prognostic value of baseline PET metrics in LS-SCLC. Neither SUVmax nor other analyzed PET metrics demonstrated significant correlation with OS or LRF. MTV was correlated with DF and DFS, but this association was no longer significant after adjustment for other clinical factors. This analysis suggests that pre-treatment PET scans, even with the use of advanced metrics, do not have independent prognostic value for outcomes in LS-SCLC patients after CRT.

Prognostic value of metabolic tumour volume and total lesion glycolysis measured by 18F‐fluorodeoxyglucose positron emission tomography/computed tomography in small cell lung cancer: A systematic review and meta‐analysis

“…), and that from the fixed effects model was 2.10 (95% CI 1.77–2.50). There was a high level of heterogeneity among the six studies ( I 2 = 87%) . The combined HR of TLG for OS from the random effects model was 1.61 (95% CI: 1.24–2.07; Fig.…”

“…We reviewed the remaining full text for nine articles; one study that calculated the HRs by a 10‐cm 3 increase in MTV and TLG was excluded, while one study was excluded because it did not provide data for HRs and lacked sufficient information to enable a calculation of the HR with corresponding 95% CI . The remaining seven articles all conformed to the inclusion criteria and had sufficient information to allow calculation of HRs . Both MTV and TLG were measured in three studies .…”

“…The remaining seven articles all conformed to the inclusion criteria and had sufficient information to allow calculation of HRs . Both MTV and TLG were measured in three studies . while, only MTV was measured in the other four studies .…”

“…This included primary tumour, lymph nodes, and distant metastases. Three studies measured MTV and TLG only in the thorax (MTV TRX and TLG TRX ) . The remaining study evaluated both MTV WB and MTV TRX .…”

18F-Fludeoxyglucose PET/CT in SCLC: Analysis of the CONVERT Randomized Controlled Trial

“…Meta-analysis of small retrospective and nonrandomized prospective studies demonstrated the prognostic significance of pretreatment 18 F-FDG PET volumetric and metabolic parameters in SCLC, 35 but these results are inconsistent. 36 Complete data on pretreatment 18 F-FDG PET parameters in our study were unavailable. A separate exploratory analysis on the prognostic significance of 18 F-FDG PET volumetric and metabolic parameters in patients recruited to CONVERT from UK centers is ongoing.…”