title: Conversion of the helical tomotherapy plans to the step-and-shoot IMRT plans for patients with hip prosthesis during radiotherapy for prostate cancer.
abstract: OBJECTIVE
  To evaluate the SharePlan software in conversion of helical tomotherapy (HT) to a step and shoot IMRT (sIMRT) for patients with high-risk prostate cancer and hip prosthesis.
  
  
  METHODS
  Analysis was performed for 16 consecutive patients treated on HT. The HT plans were converted to sIMRT plans. 3DCRT, sliding window IMRT (dIMRT) and VMAT plans for a c-arm linear accelerator (CLA) were created manually. The doses in planning target volume (PTV), bladder, rectum, bowels, femoral heads and hip prosthesis were compared using: (i) a qualitative analysis of doses in averaged dose-volume histograms, (ii) a quantitative, ranking procedure performed for each patient separately, and (iii) statistical testing based on the Friedman ANOVA and Nemenyi method.
  
  
  RESULTS
  For the bladder, rectum, and femoral head, the best dose distributions were observed for HT and sIMRT and then for dIMRT, VMAT, and finally for 3DCRT (p-values were, respectively, 0.002, 0.004 and p = 0.024). For the bowels, 3DCRT was significantly different from the rest of the techniques (p = 0.009). For the hip prosthesis, the differences were only between 3DCRT and HT/sIMRT (p = 0.038).
  
  
  CONCLUSIONS
  The SharePlan is an efficient tool for the conversion of HT plans for patients with prostate cancer and hip prosthesis. Dose distributions in sIMRT and in HT plans are similar and are generally better than in CLA plans.
authors.affiliation: Department of Medical Physics, Greater Poland Cancer Centre, Poznan, Poland.
authors.forename: Maria
authors.initials: M
authors.lastname: Olmińska
authors.affiliation: Department of Medical Physics, Greater Poland Cancer Centre, Poznan, Poland; Department of Electroradiology, Poznan University of Medical Sciences, Poznan, Poland. Electronic address: tomasz.piotrowski@me.com.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Piotrowski
authors.affiliation: Department of Medical Physics, Greater Poland Cancer Centre, Poznan, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Litoborska
authors.affiliation: Department of Medical Physics, Greater Poland Cancer Centre, Poznan, Poland; Department of Technical Physics, Poznan University of Technology, Poznan, Poland.
authors.forename: Bartosz
authors.initials: B
authors.lastname: Pawałowski
authors.affiliation: Department of Medical Physics, Greater Poland Cancer Centre, Poznan, Poland.
authors.forename: Agata
authors.initials: A
authors.lastname: Jodda
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D015992:Body Mass Index; D005269:Femur / Q000528:radiation effects; D006622:Hip Prosthesis; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D010315:Particle Accelerators; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D012007:Rectum / Q000528:radiation effects; D036542:Tomography, Spiral Computed / Q000379:methods*; D001743:Urinary Bladder / Q000528:radiation effects
keywords: Helical tomotherapy; Hip prosthesis; Prostate cancer; SharePlan