RETROSPECTIVE ANALYSIS OF LUNG CANCER TREATMENT PLANS OBTAINED BY USING THREE DIFFERENT RADIOTHERAPY TECHNIQUES

Abstract

It is aimed to compare the target volume and critical organ doses using three dimensional conformal radiotherapy (3DCRT), intensity modulated RT (IMRT) and volumetric arc therapy (VMAT) techniques in lung cancer treated with RT.

For this study; 50 patients with non-small cell lung cancer (NSCLC) who were treated with curative RT were selected and 3DCRT, IMRT and VMAT treatment plans were created. Homogeneity index, conformity index, planning tumor volume (PTV) and dose values ​​of critical organs were compared.

There was no significant difference between treatment plans in terms of D_mean (p = 0,080) value of PTV; but D_98% (p = 0.001) superior with VMAT technique. The VMAT technique was found to be superior to the other techniques for percent volume of lung receiving more than 5 Gray (V₅) (p = 0.001).

As a result; in all three RT techniques the target volume received the desired dose; it is understood that the VMAT technique is superior in terms of reducing side effects, especially radiation pneumonia. We can say that the current treatment approach is VMAT technique in the RT of patients with lung cancer in the light of technological developments.

Keywords

• Doses of Organs at Risk,Intensity Modulated Radiotherapy,Lung cancer,Three Dimensional Conformal Radiotherapy,Volumetric Modulated Arc Therapy

Üç Farklı Radyoterapi Tekniği Kullanılarak Elde Edilmiş Akciğer Kanseri Tedavi Planlarının Retrospektif Olarak İncelenmesi

Abstract

Akciğer kanserinin radyoterapi (RT) ile tedavisinde; üç boyutlu konformal radyoterapi (3BKRT), yoğunluk ayarlı radyoterapi (YART) ve volümetrik ark terapi (VMAT) teknikleri kullanılarak hedef volüm ile kritik organ dozlarının karşılaştırılması amaçlanmıştır.

Bu çalışma için; küratif RT ile tedavi edilen 50 küçük hücreli dışı akciğer kanseri (KHDAK) tanılı hasta seçilerek, 3BKRT, YART ve VMAT tedavi planları oluşturuldu. Homojenite indeksi, konformite indeksi, planlama tümör volümü (PTV) ve kritik organların aldığı doz değerleri karşılaştırıldı.  

Tedavi planları arasında PTV’nin D_mean (p= 0,080) değeri açısından anlamlı fark görülmedi; ancak D_98% (p= 0,001) değeri VMAT tekniğinde üstün bulundu. Tüm akciğerin 5 Gy alan (V₅) % değeri için (p= 0,001) VMAT tekniğinin diğer tekniklere göre daha üstün olduğu görüldü.

Sonuç olarak; her üç RT tekniğinde hedef volümün istenen dozu aldığı ancak; özellikle radyasyon pnömonisi gibi yan etkilerin azaltılması açısından VMAT tekniğinin daha üstün olduğu anlaşılmıştır. Teknolojik gelişmeler ışığında akciğer kanserli hastaların RT’sinde güncel tedavi yaklaşımının VMAT tekniği olduğunu söyleyebiliriz.

Keywords

• Akciğer kanseri,Üç Boyutlu Konformal Radyoterapi,Riskli Organ Dozları,Volümetrik Ark Terapi,Yoğunluk Ayarlı Radyoterapi

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