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

Year 2018, Volume: 44 Issue: 2, 83 - 88, 01.08.2018

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

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

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

References

• 1) Rengan R, Chetty IJ, Decker R, Langer CJ, O’Meara WP, Movsas B (eds). Lung Cancer. In: Halperin EC, Wazer DE, Perez CA, Brady LW, eds. Principles and Practice of Radiation Oncology, 6th ed. Philadelphia, LWW, 2013; 938-973.
• 2) Ming X, Feng Y, Liu H, et al. Cardiac exposure in the dynamic conformal arc therapy, intensity-modulated radiotherapy and volumetric modulated arc therapy of lung cancer. PloS one, 2015, 10.12: e0144211.
• 3) Willner J, Jost A, Baier K, Flentje M. A little to a lot or a lot to a little?. Strahlentherapie und Onkologie 2003;179.8:548-556.
• 4) Zhao Y, Chen L, Zhang S et al. Predictive factors for acute radiation pneumonitis in postoperative intensity modulated radiation therapy and volumetric modulated arc therapy of esophageal cancer. Thoracic cancer 2015;6.1:49-57.
• 5) Okumus D, Sarihan S, Gozcu S, Sigirli D. The relationship between dosimetric factors, side effects, and survival in patients with non–small cell lung cancer treated with definitive radiotherapy. Medical Dosimetry, 2017, 42.3: 169-176.
• 6) Christodoulou M, Bayman N, McCloskey P, Rowbottom C, Faivre-Finn C. New radiotherapy approaches in locally advanced non-small cell lung cancer. European journal of cancer 2014;50.3:525-534.
• 7) Bezjak A, Rumble RB, Rodrigues G et al. Intensity-modulated radiotherapy in the treatment of lung cancer. Clinical oncology 2012;24.7:508-520.
• 8) Zhang J, Yu X-L, Zheng G-F, Zhao F. Intensity-modulated radiotherapy and volumetric-modulated arc therapy have distinct clinical advantages in non-small cell lung cancer treatment. Medical Oncology, 2015, 32.4: 94.
• 9) Jiang X, Li T, Liu Y et al. Planning analysis for locally advanced lung cancer: dosimetric and efficiency comparisons between intensity-modulated radiotherapy (IMRT), single-arc/partial-arc volumetric modulated arc therapy (SA/PA-VMAT). Radiation Oncology, 2011;6.1:140.
• 10) https://icru.org
• 11) Shi A, Zhu G, Wu H, et al. Analysis of clinical and dosimetric factors associated with severe acute radiation pneumonitis in patients with locally advanced non-small cell lung cancer treated with concurrent chemotherapy and intensity-modulated radiotherapy. Radiation oncology, 2010, 5.1: 35
• 12) Zhao N, Yang R, Wang J, Zhang X, Li J. An IMRT/VMAT technique for nonsmall cell lung cancer. BioMed research international, 2015, 2015.
• 13) Liao Z X, Komaki R R, Thames H D, et al. Influence of technologic advances on outcomes in patients with unresectable, locally advanced non–small-cell lung cancer receiving concomitant chemoradiotherapy. International Journal of Radiation Oncology• Biology• Physics, 2010, 76.3: 775-781.
• 14) Zhao Y, Chen L, Zhang S et al. Predictive factors for acute radiation pneumonitis in postoperative intensity modulated radiation therapy and volumetric modulated arc therapy of esophageal cancer. Thoracic cancer 2015;6.1:49-57.
• 15) McGrath S D, Matuszak M M, Yan D, et al. Volumetric modulated arc therapy for delivery of hypofractionated stereotactic lung radiotherapy: A dosimetric and treatment efficiency analysis. Radiotherapy and Oncology, 2010, 95.2: 153-157
• 16) Fleckenstein J, Eschler A, Kremp K, Kremp S, Rübe C. Dose distribution and tumor control probability in out-of-field lymph node stations in intensity modulated radiotherapy (IMRT) vs 3D-conformal radiotherapy (3D-CRT) of non-small-cell lung cancer: an in silico analysis. Radiation Oncology, 2015, 10.1: 178.
• 17) Chan O S H, Lee M C H, Hung A W M, et al. The superiority of hybrid-volumetric arc therapy (VMAT) technique over double arcs VMAT and 3D-conformal technique in the treatment of locally advanced non-small cell lung cancer–a planning study. Radiotherapy and Oncology, 2011, 101.2: 298-302.