title: Proliferation PET image to characterize pathological spatial features in patients with non-small cell lung cancer: a pilot study.
abstract: OBJECTIVE
  (18)F-FLT-PET imaging was proposed as a tool for measuring in vivo tumor cell proliferation and detecting sub-volumes to propose escalation in radiotherapy. The aim of this study was to validate whether high FLT uptake areas in (18)F-FLT PET/CT are coincident with tumor cell proliferation distribution indicated by Ki-67 staining in non-small cell lung cancer, thus provide theoretical support for the application of dose painting guided by (18)F-FLT PET/CT.
  
  
  METHODS
  Twelve treatment naive patients with biopsy proven NSCLC underwent (18)F-FLT PET/CT scans followed by lobectomy were enrolled. The surgical specimen was dissected into 4-7 μm sections at approximately 4-mm intervals. The best slice was sort out to complete Ki-67 staining. Maximum Ki-67 labelling Index and SUVmax of the corresponding PET image was calculated. The correlation between Ki-67 Labelling Index and SUVmax of FLT was determined using Spearman Correlation analysis. High uptake areas and high proliferating areas were delineated on the two images, respectively, and their location was compared.
  
  
  RESULTS
  The maximal SUV was 3.26 ± 0.97 (1.96-5.05), maximal Ki-67 labeling index was 49% ± 27.56% (5%-90%). Statistical analysis didn't reveal a significant correlation between them (r = -0.157, P = 0.627, > 0.05). 9 patients can contour high proliferating area on Ki-67 staining slice, and eight can contour the high uptake areas. In 4 patients, we can observe a generally close distribution of high uptake areas and high proliferating areas, in one patient, both the uptake level and proliferation status was low, while the others didn't not find a significant co-localization.
  
  
  CONCLUSIONS
  Noninvasive (18)F-FLT PET assessing the proliferative status may be a valuable aid to guide dose painting in NSCLC, but it needs to be confirmed further.
authors: Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong Academy of Medical Sciences Jinan, China ; Department of Oncology, Affiliated Hospital of Taishan Medical University Taian, China.
authors: Xiao-Ting
authors: XT
authors: Chen
authors: Department of Cardiothoracic Surgery, Qilu Hospital,Shandong University Jinan, China.
authors: Xin
authors: X
authors: Zhao
authors: Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong Academy of Medical Sciences Jinan, China.
authors: Zhen-Hua
authors: ZH
authors: Gao
authors: Department of Pathology, Shandong Cancer Hospital and Institute Jinan, China.
authors: Yong-Sheng
authors: YS
authors: Gao
authors: Department of Thoracic Surgery, Shandong Cancer Hospital and Institute Jinan, China.
authors: Bai-Jiang
authors: BJ
authors: Zhang
authors: Department of Nuclear Medicine, Shandong Cancer Hospital and Institute Jinan, China.
authors: Zheng
authors: Z
authors: Fu
authors: Department of Pathology, Shandong Cancer Hospital and Institute Jinan, China.
authors: Dian-Bin
authors: DB
authors: Mu
authors: Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong Academy of Medical Sciences Jinan, China.
authors: Jin-Ming
authors: JM
authors: Yu
authors: Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong Academy of Medical Sciences Jinan, China.
authors: Xue
authors: X
authors: Meng
keywords: 18F-FLT PET; non-small-cell lung cancer; pathological spatial validation