SUVmax Predicts Disease Progression after Stereotactic Ablative Radiotherapy in Stage I Non-small Cell Lung Cancer

Abstract

Fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) is gaining evidence as a predictive factor in non-small cell lung cancer (NSCLC). Stereotactic ablative radiotherapy (SABR) is the standard treatment in early-stage NSCLC when a patient is unsuitable for surgery. We performed a study to assess the prognostic clinical significance of PET-CT after SABR in early-stage NSCLC. Materials and Methods Seventy-six patients with stage I NSCLC treated with SABR were investigated. Total radiation dose ranged from 36 to 63 Gy in three to eight fractions depending on tumor location and size. Respiratory motion control was implemented at simulation and during treatment. PET-CT prior to SABR was performed in 66 patients (86.8%). Results Median follow-up time was 32 months (range, 5 to 142 months). Local control rate at 1, 2, and 5 years were 95.9%, 92.8%, and 86.7%, respectively. Overall survival (OS) at 1, 2, and 5 years were 91.0%, 71.3%, and 52.1% respectively. Cause-specific survival at 1, 2, and 5 years were 98.6%, 93.1%, and 84.3% respectively. Tumor size and pre-SABR maximal standardized uptake value (SUVmax) demonstrated statistical significance in the Kaplan-Meier survival analyses with log-rank test. In multivariate analyses pre-SABR SUVmax remained statistically significant in correlation to OS (p=0.024; hazard ratio [HR], 3.2; 95% confidence interval [CI], 1.2 to 8.8) and with marginal significance in regards to regional progressionfree survival (p=0.059; HR, 32.5; 95% CI, 2.6 to 402.5). Conclusion Pre-SABR SUVmax demonstrated a predictive power in statistical analyses. Tumors with SUVmax above 6 at diagnosis were associated with inferior outcomes.

Evaluation of Response to Stereotactic Body Radiation Therapy For Non-Small Cell Lung Cancer: PET Response Criteria in Solid Tumors (PERCIST) Versus Response Evaluation Criteria in Solid Tumors (RECIST)

“…We con rmed clinical stage to be univariate risk factors in the present study, whilst location, tumor T stage, node metastasis were not signi cant risk factors in our univariate analysis [26,27]. These ndings do not agree with previous reports that tumor T stage is risk factors for the outcome in early NSCLC patients [28] which may be due to the small size of study population.…”

Evaluation of response to stereotactic body radiation therapy for nonsmall cell lung cancer: PET response criteria in solid tumors versus response evaluation criteria in solid tumors

“…We confirmed clinical stage to be univariate risk factors in the present study, whereas location, tumor T stage, and node metastasis were NS risk factors in our univariate analysis [26,27]. These findings do not agree with previous reports that the tumor T stage is a risk factor for the outcome in early NSCLC patients [28], which may be due to the small size of the study population.…”

Tumor to liver maximum standardized uptake value ratio of FDG-PET/CT parametersBBpredicts tumor treatment response and survival of stage III non-small cell lung cancer

“…18 FDG-PET/CT, which is a tool to evaluate tumor metabolism and reveal the uptake of FDG by tumor cells, has been applied widely for early detection of tumor locations and the decision-making of anticancer intervention. Some previous studies have reported that several baseline parameters derived from PET/CT before initiation of treatment, such as SUVmax and SUVmean might predict clinical treatment response and recurrence in patients with various types of human cancers [28][29][30][31][32] . A previous retrospective study of stage III NSCLC patients showed that SUVmax signi cantly affected the OS of patients with NSCLC, which is consistent with our nding that the patients with a higher SUVmax (SUVmax ≥ 14) had a worse OS than those with a lower SUVmax (SUVmax < 14) (median of OS: 18 months vs. 25 months) after de nitive chemoradiotherapy 33 .…”