Dosimetric Evaluation of Intensity Modulated Radiotherapy and 4-Field 3-D Conformal Radiotherapy in Prostate Cancer Treatment

Abstract

Objective: The purpose of this dosimetric study is the targeted dose homogeneity and critical organ dose comparison of 7-field Intensity Modulated Radiotherapy (IMRT) and 3-D 4-field conformal radiotherapy. Study Design: Cross sectional study. Material and Methods: Twenty patients with low and moderate risk prostate cancer treated at Gülhane Military Medical School Radiation Oncology Department between January 2009 and December 2009 are included in this study. Two seperate dosimetric plans both for 7-field IMRT and 3D-CRT have been generated for each patient to comparatively evaluate the dosimetric status of both techniques and all the patients received 7-field IMRT. Results: Dose-comparative evaluation of two techniques revealed the superiority of IMRT technique with statistically significantly lower femoral head doses along with reduced critical organ dose-volume parameters of bladder V60 (the volume receiving 60 Gy) and rectal V40 (the volume receiving 40 Gy) and V60. Conclusion: It can be concluded that IMRT is an effective definitive management tool for prostate cancer with improved critical organ sparing and excellent dose homogenization in target organs of prostate and seminal vesicles. Turkish Anahtar Kelimeler: Prostat kanseri, YART, 3-B Konformal RT Amaç: Bu dozimetrik çalışmanın amacı 7-alan Yoğunluk Ayarlı Radyoterapi (YART) ve 3-Boyutlu 4-Alan Konformal Radyoterapi (3BKRT)'nin hedef doz homojenitesi ve kritik organ dozlarının karşılaştırılmasıdır. Gereç ve Yöntemler: Gülhane Askeri Tıp Fakültesi Radyasyon Onkolojisi Anabilim Dalı'nda Ocak 2009 ve Aralık 2009 yılları arasında düşük ve orta riskli prostat kanseri tanısıyla tedavi edilen 20 hasta bu çalışmaya dahil edildi. 7-alan Yoğunluk Ayarlı Radyoterapi (YART) ve 3BKRT'nin her ikisi için ayrı iki dozimetrik plan 7-alan YART uygulanan tüm hastaları ve her iki tekniğin dozimetrik durumunu değerlendirmek için düzenlendi. Bulgular: İki tekniğin doz karşılaştırmalı değerlendirilmesi YART tekniğinin istatistiksel olarak belirgin oranda düşük femur başı dozları ile azalmış mesane V60( 60 Gy alan volüm) ve rektal V40 ( 40 Gy alan volüm) kritik organ doz volüm parametreleriyle üstünlüğünü gösterdi. Sonuç: Sonuç olarak YART gelişmiş kritik organ koruma ve hedef organlar olan prostat ve seminal veziküllerin mükemmel doz homojenizasyonuyla prostat kanserinde etkili ve küratif bir tedavi aracıdır.

Keywords

• Intensity-modulated radiotherapy, prostate cancer, three-dimensional conformal radiotherapy

Dosimetric Evaluation of Intensity Modulated Radiotherapy and 4-Field 3-D Conformal Radiotherapy in Prostate Cancer Treatment

Öz

Kaynakça

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