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

Yıl 2018, Cilt: 44 Sayı: 2, 83 - 88, 01.08.2018

Duygu Bolat Oğuz Aydın , Sema Gözcü Tunç Zenciye Kıray Süreyya Sarıhan

https://doi.org/10.32708/uutfd.424493

Öz

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.

Anahtar Kelimeler

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

Öz

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.

Anahtar Kelimeler

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

Kaynakça

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