L-型氨基酸转运体-1（LAT1）是一种在各种肿瘤类型中特异性表达的转运体，在正常器官中的表达较小。我们之前在一项临床前研究中证明了18F-氟硼基苯丙氨酸（18F-FBPA）作为选择性的LAT1 PET探针。在本研究中，我们利用18F-FBPA PET和免疫荧光染色评估了术前患有肺部或纵隔肿瘤的患者的LAT1表达。研究人群包括组织病理学诊断的患者（n = 55）：原发性肺癌（n = 21），肺转移（n = 6），纵隔肿瘤（n = 15）和良性病变（n = 13）。注射18F-FBPA（232±32 MBq）后1小时进行PET扫描。利用LAT1抗体在切除的肿瘤组织切片上进行免疫荧光染色。将LAT1染色按照4级评分，并与18F-FBPA PET的最大标准摄入值（SUVmax）进行比较。 结果显示18F-FBPA PET的SUVmax与LAT1在免疫荧光染色中的表达呈正相关（r=0.611，P＜0.001）。18F-FBPA的SUVmax在LAT1表达3级为3.92 ± 1.46，在2级为3.21 ± 1.82，在1级为2.33 ± 0.93，在0级为1.50 ± 0.39。虽然18F-FBPA PET在肺癌和纵隔肿瘤中的摄取呈现变异性，但良性病变的SUVmax明显低于恶性病变（P＜0.01）。 18F-FBPA PET的摄取反映了肺部和纵隔肿瘤中LAT1的表达水平。结果表明，18F-FBPA PET可在预治疗评估中用于肿瘤的精确表征。 版权所有 © 2023 作者。由Wolters Kluwer Health, Inc出版。

L-type amino acid transporter-1 (LAT1) is a tumor-specific transporter expressed in various tumor types, with minimal expression in normal organs. We previously demonstrated 18F-fluoro-borono-phenylalanine (18F-FBPA) as a selective PET probe for LAT1 in a preclinical study. Herein, we evaluated LAT1 expression in preoperative patients with lung or mediastinal tumors using 18F-FBPA PET and immunofluorescence staining.The study population included patients with histopathological diagnosis (n = 55): primary lung cancers (n = 21), lung metastases (n = 6), mediastinal tumors (n = 15), and benign lesion (n = 13). PET scanning was performed 1 hour after the injection of 18F-FBPA (232 ± 32 MBq). Immunofluorescence staining was performed on the resected tumor sections using LAT1 antibody. LAT1 staining was graded on a 4-grade scale and compared with the SUVmax on 18F-FBPA PET.A positive correlation was observed between the SUVmax of 18F-FBPA PET and LAT1 expression by immunofluorescence staining (r = 0.611, P < 0.001). The SUVmax of 18F-FBPA was 3.92 ± 1.46 in grade 3, 3.21 ± 1.82 in grade 2, 2.33 ± 0.93 in grade 1, and 1.50 ± 0.39 in grade 0 of LAT1 expression. Although 18F-FBPA PET showed variable uptake in lung cancers and mediastinal tumors, benign lesions showed significantly lower SUVmax than those in malignant lesions (P < 0.01).Uptake on 18F-FBPA PET reflected the expression level of LAT1 in lung and mediastinal tumors. It was suggested that 18F-FBPA PET can be used for the precise characterization of the tumor in pretreatment evaluation.Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.