Tumor angiogenesis at baseline identified by ¹⁸F-Alfatide II PET/CT may predict survival among patients with locally advanced non-small cell lung cancer treated with concurrent chemoradiotherapy

Abstract

Background

The study investigated the predictive value of tumor angiogenesis observed by ¹⁸F-ALF-NOTA-PRGD2 II (denoted as ¹⁸F-Alfatide II) positron emission tomography (PET)/computed tomography (CT) before concurrent chemoradiotherapy (CCRT) for treatment response and survival among patients with locally advanced non-small cell lung cancer (LA-NSCLC).

Methods

Patients with unresectable stage IIIA or IIIB NSCLC (AJCC Cancer Staging 7th Edition) who received CCRT were included in this prospective study. All patients had undergone ¹⁸F-Alfatide PET/CT scanning before CCRT, and analyzed parameters included maximum uptake values (SUV _max) of primary tumor (SUV _P) and metastatic lymph nodes (SUV _LN) and mean uptake value of blood pool (SUV _blood). Tumor-to-background ratios (TBRs) and changes in tumor diameter before and after CCRT (ΔD) were calculated. The ratios of SUV _P to SUV _blood, SUV _LN to SUV _blood, and SUV _P to SUV _LN were denoted as TBR _P, TBR _LN, and T/LN. Short-term treatment response, progression-free survival (PFS), and overall survival (OS) were evaluated.

Results

Of 38 enrolled patients, 28 completed CCRT. SUV _P, SUV _LN, TBR _P, TBR _LN and T/LN showed significant correlation with PFS (all P < 0.05). SUV _P was negatively correlated with OS ( P = 0.005). SUV _P and TBR _P were higher in non-responders than in responders (6.55 ± 2.74 vs. 4.61 ± 1.94, P = 0.039; 10.49 ± 7.58 vs. 7.73 ± 6.09, P = 0.023). ΔD was significantly greater in responders (2.78 ± 1.37) than in non-responders (-0.16 ± 1.33, P < 0.001). Exploratory receiver operating characteristic curve analysis identified TBR _P (area under the curve [AUC] = 0.764, P = 0.018), with a cutoff value of 6.52, as the only parameter significantly predictive of the response to CCRT, with sensitivity, specificity, and accuracy values of 71.43%, 78.57%, and 75.00%, respectively. ROC curve analysis also identified SUV _P (AUC = 0.942, P < 0.001, cutoff value 4.64) and TBR _P (AUC = 0.895, P = 0.001, cutoff value 4.95) as predictive of OS with high sensitivity (84.21%, 93.75%), specificity (100.00%, 66.67%), and accuracy (89.29%, 82.14%).

Conclusions

Evaluation of tumor angiogenesis by ¹⁸F-Alfatide II at baseline may be useful in predicting the short-term response to CCRT as well as PFS and OS in patients with LA-NSCLC.