title: Evaluation of the therapeutic effect of radiotherapy on cervical cancer using magnetic resonance imaging.
abstract: OBJECTIVE
  This study was performed to evaluate magnetic resonance imaging (MRI) in determining the therapeutic effect of radiotherapy (RT) on cervical cancer.
  
  
  METHODS
  Serial MRI studies were performed in 42 patients with predominantly advanced cervical cancer before, during, and after radiotherapy. Patients underwent external irradiation combined with high-dose-rate intracavitary (HDR) brachytherapy. T-2 weighted spin-echo pulse sequences with long repetition and echo times were used at a field strength of 1.5 T. Multiple punch biopsies of the cervix were obtained from the high-signal intensity area in all patients at the same time as the MRI.
  
  
  RESULTS
  In biopsies performed immediately after RT, no residual tumors were found in 36 patients (86%); in 6 patients, residual tumors were observed. The simultaneous MRI study demonstrated no high-signal intensity on T2-weighted images in 28 patients. A high-signal area was observed in 14 patients, and this disappeared 3 months after RT in 8 patients with a negative histological study. The sensitivity, specificity, and accuracy of MRI studies at 3 months after RT were 100%. When the relationship between reduction of tumor volume at 30 Gy and local tumor control was analyzed, every patient with a reduction under 30% gained local control. Also, patients with no residual tumors 3 months after RT gained local control.
  
  
  CONCLUSIONS
  MRI studies performed at 30 Gy of external irradiation and 3 months after RT were predictive factors of local control.
authors.affiliation: Division of Radiation Oncology, Chiba Cancer Center, Chiba City, Japan. khatano@internet.chiba-cc.pref.chiba.jp
authors.forename: K
authors.initials: K
authors.lastname: Hatano
authors.forename: Y
authors.initials: Y
authors.lastname: Sekiya
authors.forename: H
authors.initials: H
authors.lastname: Araki
authors.forename: M
authors.initials: M
authors.lastname: Sakai
authors.forename: T
authors.initials: T
authors.lastname: Togawa
authors.forename: Y
authors.initials: Y
authors.lastname: Narita
authors.forename: Y
authors.initials: Y
authors.lastname: Akiyama
authors.forename: S
authors.initials: S
authors.lastname: Kimura
authors.forename: H
authors.initials: H
authors.lastname: Ito
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000532:radiotherapy*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D001918:Brachytherapy; D002294:Carcinoma, Squamous Cell / Q000473:pathology / Q000532:radiotherapy*; D002584:Cervix Uteri / Q000473:pathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D011879:Radiotherapy Dosage; D016896:Treatment Outcome; D002583:Uterine Cervical Neoplasms / Q000473:pathology / Q000532:radiotherapy*