Dosimetric comparison of volumetric modulated Arc therapy, step-and-shoot, and sliding window IMRT for prostate cancer

Journal Article · Tue Oct 23 04:00:00 EDT 2012 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4764589· OSTI ID:22075684

Schnell, Erich; Young, Julie; Hildebrand, Kim; Algan, Ozer; Syzek, Elizabeth; Herman, Terence; Ahmad, Salahuddin ^[1]

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1. Department of Radiation Oncology, University of Oklahoma Health Sciences Center 800 N.E. 10th St., OKCC L100, Oklahoma City, OK 73104 (United States)

This study aims to evaluate treatment plans generated by Step-and-Shoot (SS), Sliding Window (SW) and Volumetric Modulated Arc Therapy (VMAT) in order to assess the differences in dose volume histograms of planning target volume (PTV) and organs at risk (OAR), conformity indices, radiobiological evaluations, and plan quality for prostate cancer cases. Six prostate cancer patients treated in our center were selected for this retrospective study. Treatment plans were generated with Eclipse version 8.9 using 10 MV photon beams. For VMAT, Varian Rapid Arc with 1 or 2 arcs, and for SS and SW IMRT, 7-9 fields were used. Each plan had three PTVs with prescription doses of 81, 59.4, and 45 Gy to prostate, to prostate and lymph nodes, and to pelvis, respectively. Doses to PTV and OAR and the conformal indices (COIN) were compared among three techniques. The equivalent uniform dose (EUD), tumor control probability (TCP) and normal tissue complication probability (NTCP) were calculated and compared. The mean doses to the PTV prostate on average were 83 Gy and the percent differences of mean dose among all techniques were below 0.28. For bladder and rectum, the percent differences of mean dose among all techniques were below 2.2. The COIN did not favour any particular delivery method over the other. The TCP was higher with SS and SW for four patients and higher with VMAT for two patients. The NTCP for the rectum was the lowest with VMAT in five out of the six patients. The results show similar target coverage in general.

• OSTI ID: 22075684
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1494; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

61 RADIATION PROTECTION AND DOSIMETRY
62 RADIOLOGY AND NUCLEAR MEDICINE
BLADDER
COMPARATIVE EVALUATIONS
CONTROL
GAMMA DOSIMETRY
LYMPH NODES
NEOPLASMS
PATIENTS
PELVIS
PHOTON BEAMS
PROBABILITY
PROSTATE
RADIATION DOSES
RADIOTHERAPY
RECTUM