title: Prospective evaluation of microscopic extension using whole-mount preparation in patients with hepatocellular carcinoma: Definition of clinical target volume for radiotherapy.
abstract: BACKGROUND
  To define the clinical target volume (CTV) for radiotherapy in patients with hepatocellular carcinoma (HCC).
  
  
  METHODS
  A prospective study was conducted to histologically evaluate the presence and the distance of microscopic extension (ME) for resected HCC on the basis of examination of whole-mount preparations of carcinoma tissue sections.
  
  
  RESULTS
  A total of 380 whole-mount slides prepared from tumor samples of 76 patients with HCC were examined. Patients with elevated pretreatment AFP levels exhibited higher risk of ME as compared to those with normal pretreatment AFP levels (93.9% vs. 69.8%, P < 0.01). ME positivity was 16.7% for Grade 1, 79.1% for Grade 2, and 96.3% for Grade 3 tumors (P < 0.01). The mean distance of ME was 0.0 ± 0.1 mm (range 0-0.2 mm) for Grade 1, 0.9 ± 0.9 mm (range 0-4.5 mm) for Grade 2, and 1.9 ± 1.9 mm (range 0-8.0 mm) for Grade 3 tumors (P < 0.01).
  
  
  CONCLUSIONS
  The CTV margins for tumor Grades 1, 2, and 3 HCC, are recommended to be 0.2 mm, 4.5 mm, and 8.0 mm beyond the gross tumor margin, respectively, to account for possible ME of the tumors in all patients.
authors: Department of Radiation Oncology, Cancer Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, PR China.
authors: Weihu
authors: W
authors: Wang
authors: Xiaoli
authors: X
authors: Feng
authors: Tao
authors: T
authors: Zhang
authors: Jing
authors: J
authors: Jin
authors: Shulian
authors: S
authors: Wang
authors: Yueping
authors: Y
authors: Liu
authors: Yongwen
authors: Y
authors: Song
authors: Xinfan
authors: X
authors: Liu
authors: Zihao
authors: Z
authors: Yu
authors: Yexiong
authors: Y
authors: Li
mesh_terms: D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000473:pathology*; D005260:Female; D006652:Histological Techniques; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018787:Radiation Oncology / Q000379:methods; D011879:Radiotherapy Dosage