title: More accurate definition of clinical target volume based on the measurement of microscopic extensions of the primary tumor toward the uterus body in international federation of gynecology and obstetrics Ib-IIa squamous cell carcinoma of the cervix.
abstract: OBJECTIVE
  To more accurately define clinical target volume for cervical cancer radiation treatment planning by evaluating tumor microscopic extension toward the uterus body (METU) in International Federation of Gynecology and Obstetrics stage Ib-IIa squamous cell carcinoma of the cervix (SCCC).
  
  
  METHODS
  In this multicenter study, surgical resection specimens from 318 cases of stage Ib-IIa SCCC that underwent radical hysterectomy were included. Patients who had undergone preoperative chemotherapy, radiation, or both were excluded from this study. Microscopic extension of primary tumor toward the uterus body was measured. The association between other pathologic factors and METU was analyzed.
  
  
  RESULTS
  Microscopic extension toward the uterus body was not common, with only 12.3% of patients (39 of 318) demonstrating METU. The mean (±SD) distance of METU was 0.32 ± 1.079 mm (range, 0-10 mm). Lymphovascular space invasion was associated with METU distance and occurrence rate. A margin of 5 mm added to gross tumor would adequately cover 99.4% and 99% of the METU in the whole group and in patients with lymphovascular space invasion, respectively.
  
  
  CONCLUSIONS
  According to our analysis of 318 SCCC specimens for METU, using a 5-mm gross tumor volume to clinical target volume margin in the direction of the uterus should be adequate for International Federation of Gynecology and Obstetrics stage Ib-IIa SCCC. Considering the discrepancy between imaging and pathologic methods in determining gross tumor volume extent, we recommend a safer 10-mm margin in the uterine direction as the standard for clinical practice when using MRI for contouring tumor volume.
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province, China.
authors.forename: Wen-Jia
authors.initials: WJ
authors.lastname: Xie
authors.affiliation: Department of Pathology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Wu
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province, China.
authors.forename: Ren-Liang
authors.initials: RL
authors.lastname: Xue
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province, China.
authors.forename: Xiang-Ying
authors.initials: XY
authors.lastname: Lin
authors.affiliation: Department of Radiation Oncology, Stanford University, Stanford, California.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Kidd
authors.affiliation: Department of Pathology, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong Province, China.
authors.forename: Shu-Mei
authors.initials: SM
authors.lastname: Yan
authors.affiliation: Department of Radiation Oncology, Chaozhou Hospital of Chaozhou City, Guangdong Province, China.
authors.forename: Yao-Hong
authors.initials: YH
authors.lastname: Zhang
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province, China.
authors.forename: Tian-Tian
authors.initials: TT
authors.lastname: Zhai
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province, China.
authors.forename: Jia-Yang
authors.initials: JY
authors.lastname: Lu
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province, China.
authors.forename: Li-Li
authors.initials: LL
authors.lastname: Wu
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Pathology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong Province, China.
authors.forename: Hai-Hua
authors.initials: HH
authors.lastname: Huang
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province, China.
authors.forename: Zhi-Jian
authors.initials: ZJ
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province, China.
authors.forename: De-Rui
authors.initials: DR
authors.lastname: Li
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province, China. Electronic address: xieliangxi1@qq.com.
authors.forename: Liang-Xi
authors.initials: LX
authors.lastname: Xie
mesh_terms: D000328:Adult; D000367:Age Factors; D000704:Analysis of Variance; D001808:Blood Vessels / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000473:pathology* / Q000532:radiotherapy / Q000601:surgery; D002584:Cervix Uteri / Q000473:pathology; D005260:Female; D006801:Humans; D007044:Hysterectomy / Q000379:methods; D008198:Lymph Nodes / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D047368:Tumor Burden; D002583:Uterine Cervical Neoplasms / Q000473:pathology* / Q000532:radiotherapy / Q000601:surgery; D014599:Uterus / Q000473:pathology*