title: Impact of target area selection in125Iodine seed brachytherapy on locoregional recurrence in patients with non-small cell lung cancer.
abstract: Computed tomography (CT)-guided percutaneous implantation of125Iodine radioactive seeds requires the precise arrangement of seeds by tumor shape. We tested whether selecting target areas, including subclinical areas around tumors, can influence locoregional recurrence in patients with non-small cell lung cancer (NSCLC).
  
  
  
  We divided 82 patients with NSCLC into two groups. Target areas in group 1 (n = 40) were defined along tumor margins based on lung-window CT. Target areas in group 2 (n = 42) were extended by 0.5 cm in all dimensions outside tumor margins. Preoperative plans for both groups were based on a treatment plan system, which guided125I seed implantation. Six months later, patients underwent chest CT to evaluate treatment efficacy (per Response Evaluation Criteria in Solid Tumors version 1). We compared locoregional recurrences between the groups after a year of follow-up. We then used the treatment plan system to extend target areas for group 1 patients by 0.5 cm (defined as group 3 data) and compared these hypothetical group 3 planned seeds with the actual seed numbers used in group 1 patients.
  
  
  
  All patients successfully underwent implantation; none died during the follow-up period. Recurrence was significantly lower in group 2 than in group 1 ( P  < 0.05). Group 1 patients and group 3 data significantly differed in seed numbers ( P  < 0.01).
  
  
  
  Our results imply that extending the implantation area for125I seeds can decrease recurrence risk by eradicating cancerous lymph-duct blockades within the extended areas.
authors.affiliation: Department of Thoracic Surgery, The Second Hospital of Tianjin Medical University, Tianjin, China.
authors.forename: Wei-Liang
authors.initials: WL
authors.lastname: Yan
authors.affiliation: Department of Thoracic Surgery, The Second Hospital of Tianjin Medical University, Tianjin, China.
authors.forename: Jin-Shuang
authors.initials: JS
authors.lastname: Lv
authors.affiliation: Department of Thoracic Surgery, The Second Hospital of Tianjin Medical University, Tianjin, China.
authors.forename: Zhi-Yu
authors.initials: ZY
authors.lastname: Guan
authors.affiliation: Faculty of Medicine, University of Southampton, Southampton, UK.
authors.forename: Li-Yang
authors.initials: LY
authors.lastname: Wang
authors.affiliation: Department of Thoracic Surgery, The Second Hospital of Tianjin Medical University, Tianjin, China.
authors.forename: Jing-Kui
authors.initials: JK
authors.lastname: Yang
authors.affiliation: Department of Thoracic Surgery, The Second Hospital of Tianjin Medical University, Tianjin, China.
authors.forename: Ji-Xiang
authors.initials: JX
authors.lastname: Liang
mesh_terms: D000368:Aged; D001918:Brachytherapy / Q000009:adverse effects*; D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology / Q000532:radiotherapy*; D016499:Radioimmunotherapy; D014057:Tomography, X-Ray Computed
chemical_list: D007457:Iodine Radioisotopes
keywords: 
  125
  Iodine radioactive seed; non-small cell lung cancer; radioactive seed brachytherapy; target area selection; treatment plan system (TPS)