Pretreatment Tumor 18F-FDG Uptake Improves Risk Stratification Beyond RECIST 1.1 in Patients With Advanced Nonsquamous Non-Small-Cell Lung Cancer: FDG Uptake and Risk Stratification.

PURPOSE: This study investigated the prognostic role of tumor F-FDG uptake on pretreatment scans as an independent indicator and whether its addition improves risk prediction from Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1).

METHODS: We measured the SUVmax of the most F-FDG-avid tumor lesions on pretreatment scans from 222 patients (age, 60.5 ± 9.5 years; males, 55.2%) with advanced nonsquamous non-small-cell lung cancer who were enrolled in a prospective phase II clinical trial. We then examined the prognostic value of SUVmax compared with other clinical factors, including chemotherapy response according to RECIST 1.1 criteria.

RESULTS: A multivariable Cox proportional hazards model revealed that an SUVmax greater than 16.3 was an independent predictor of poor progression-free survival (hazards ratio, 3.50; 95% confidence interval, 1.89-6.51; P < 0.000) and overall survival (hazards ratio, 6.87; 95% confidence interval, 2.51-18.76; P < 0.000), whereas RECIST 1.1 did not show a significant association with any survival outcome. Furthermore, improvement was achieved by adding SUVmax to RECIST 1.1, which increased the net reclassification index (27.4%; P = 0.046) and integrated discrimination improvement (integrated discrimination improvement, 10.6%; P = 0.026). Similarly, adding RECIST 1.1 to SUVmax also improved net reclassification index (68.9%, P = 0.006) and integrated discrimination improvement (25.4%, P = 0.006) for prognosis prediction.

CONCLUSIONS: High tumor F-FDG uptake on a pretreatment scan is an independent prognostic indicator that can significantly improve risk stratification when added to RECIST 1.1 for patients with advanced nonsquamous non-small-cell lung cancer.