The comparison of 5-field conformal radiotherapy techniques for the treatment of prostate cancer: The best for femoral head sparing.
External radiotherapy is a standard treatment procedure for localized prostate cancer. Given the relatively high long term survival treatment complications have been brought in center of attention. In this planning study, between 2012 and 2014, CT simulation data of 90 consecutive high-risk prostate cancer patients were collected. In the first phase, all were planned for whole pelvis irradiation up to 46Gy in 23 daily fractions. In the second phase, only the prostate gland was the target of radiation. Next, the subjects were divided randomly into three groups and each received a unique 5field conformal radiation plan including Plan A (Gantry angle: 0, 60, 120, 240, and 300), Plan B (Gantry angles: 0, 90, 120, 240, and 270) and Plan C (Gantry angles: 0, 60, 90, 270, and 300). The total dose was 70Gy. For each patient, the rectum, bladder, and both femoral heads were contoured as the at risk organs (OAR). From dose volume histograms, the proportional dose of PTV V100, the bladder and rectum V80 and V90 and femoral head V50 and V100 were calculated in all subjects and compared across plans. A statistically significant difference in the femoral head V50 and V100 was found between our studied 5field plans so that in Plan A (beam angles: 0, 60, 120, 240 and 300) less dose was received by both heads of femur. This study suggests that 5 field treatment planning including an anterior, two anterior oblique and two posterior oblique portals to be more proper for 3D conformal radiotherapy in order to spare femoral head with acceptable PTV coverage, and bladder and rectal doses.
Department of Radiation Oncology, Hafte-e-Tir Hospital, Iran University of Medical Sciences, Shar e Rey, Tehran, Iran.
Mahkameh
M
Zare
Department of Radiation Oncology, Radiation Oncology Research Center, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: m-lashkari@sina.tums.ac.ir.
Marzieh
M
Lashkari
Department of Radiation Oncology, Radiation Oncology Research Center, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran.
Reza
R
Ghalehtaki
Department of Radiation Oncology, Imam Khomeini Hospital, Sari University of Medical Science, Sari, Iran.
Arash
A
Ghasemi
Department of Radiation Oncology, Hafte-e-Tir Hospital, Iran University of Medical Sciences, Shar e Rey, Tehran, Iran.
Hamidreza
H
Dehghan Manshadi
Department of General Surgery, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Ali
A
Mir
Department of Radiation Oncology, Hafte-e-Tir Hospital, Iran University of Medical Sciences, Shar e Rey, Tehran, Iran.
Somayeh
S
Noorollahi
Department of Radiation Oncology, Hafte-e-Tir Hospital, Iran University of Medical Sciences, Shar e Rey, Tehran, Iran.
Mahboobeh
M
Alamolhoda
D005270:Femur Head / Q000528:radiation effects*; D006801:Humans; D008297:Male; D058958:Organs at Risk; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods; D020266:Radiotherapy, Conformal / Q000379:methods*; D014057:Tomography, X-Ray Computed
Conformal radiotherapy; Dose-volume histogram; Optimization; Prostate cancer; Treatment planning