Metabolic tumor volume on FDG-PET/CT is a possible prognostic factor for Stage I lung cancer patients treated with stereotactic body radiation therapy: a retrospective clinical study

Abstract

The aim of this study was to determine whether metabolic tumor volume (MTV) and total lesion glycolysis (TLG) are associated with outcomes in Stage I lung cancer patients treated with stereotactic body radiation therapy (SBRT). Thirty-eight patients underwent [18F] fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) within 60 days before SBRT at our institution between January 2001 and December 2011. The maximum standardized uptake value (SUVmax), MTV2, MTV4, MTV6, TLG40%, TLG50% and TLG60% were calculated. Prognostic factors for overall survival (OS) and local control (LC) were analyzed using Cox's proportional hazards model, and survival curves were calculated using the Kaplan–Meier method. Receiver operating characteristics (ROC) curves of PET parameters for OS and LC were calculated. The median follow-up period for survivors was 37.7 months. Three-year OS and LC rates were 56.4% and 70.5%, respectively, and 5-year OS and LC rates were 36.8% and 70.5%, respectively. In univariate analyses, tumor diameter (P = 0.019), single dose ≥10 Gy (P = 0.017), MTV2 (P = 0.030) and MTV4 (P = 0.048) were significant predictors for OS. Tumor diameter (P < 0.001), single dose ≥10 Gy (P = 0.007), SUVmax (P = 0.035), MTV2 (P < 0.001), MTV4 (P = 0.003), MTV6 (P = 0.017), TLG40% (P < 0.001), TLG50% (P = 0.001) and TLG60% (P = 0.003) were significant predictors for LC. SUVmax was not a significant predictor for OS. We made the ROC curves at PET parameters, and the largest area under the curve value for OS was MTV2 and for LC was TLG40%. Tumor diameter, single dose ≥10 Gy, MTV2 and MTV4 are prognostic factors for OS and LC rates and MTV2 is a better prognostic factor for OS than other PET parameters.

Metabolic Tumour Volume Is Prognostic in Patients with Non-Small-Cell Lung Cancer Treated with Stereotactic Ablative Radiotherapy

“…Abelson et al 17 retrospectively reviewed 53 patients and found mtv to be prognostic of os at high-threshold mtv cutoffs (the volume of metabolically active tumour being defined as the volume having suvs above 4, 7, and 10). Takahashi et al 8 found mtv to be the imaging parameter most prognostic of os (using a threshold suv of 2) and tlg to be the parameter most prognostic of lc. The mtv has also been shown to be prognostic in patients with early-stage nsclc treated surgically 18 , in all stages of nsclc treated definitively 9 , and in other tumour sites, including esophageal cancer 19 , cervical cancer 20 , and head-and-neck cancer 21 .…”

Clinical utility of texture analysis of 18F-FDG PET/CT in patients with Stage I lung cancer treated with stereotactic body radiotherapy

“…The predictive value of PET images for clinical prognosis has been investigated. For analyzing PET images, histogram-based parameters [such as maximum standardized uptake value (SUV) and mean SUV] and volume-based parameters [such as metabolic tumor volume (MTV) and total lesion glycolysis (TLG)] have been investigated [ 5 – 9 ]. Recently, texture analysis of 18 F-FDG PET/CT images has been shown to have prognostic value in local control (LC), distant metastases and survival of patients with early-stage lung cancer treated with SBRT [ 10 – 12 ].…”

Is There Any Prognostic Significance of the Level of Change in SUVmax after SBRT in Patients with Early Stage NSCLC?

“…19,[22][23][24] For this reason, it has been followed by studies involving volume based parameters (VBP) such as metabolic tumor volume (MTV) and total glycolysis (TLG). 25 Contradictory results on this subject have been reported in a few studies. For example, Vu et al could not show any correlation between SUVmax, but Satoh et al showed that SUVmax, MTV and TLG were significantly associated with DFS.…”