The Effect of Radiotherapy Technique on Carotid Artery Dose in Patients with Early Stage Glottic Larynx Cancer

Öz

Objective: The aim of this study was to compare two radiotherapy techniques in early stage glottic laryngeal cancer patients in terms of radiotherapy dose applied to the carotid artery.

Material - Methods: In this study, we included 10 early-stage (T1/2) glottic larynx cancer patients. Both intensity-modulated radiotherapy (IMRT) and 3-dimension conformal radiotherapy (3DCRT) treatment plans were prepared for each patient. Treatment volumes (CTV, PTV) were created for all patients. The entire larynx was described as CTV to include both false and true vocal cords, anterior-posterior commissures, arytenoids, aryepiglottic folds, subglottic region. For planning target volüme (PTV), while 5-mm was added to CTV in all directions, 3-mm margin was given to protect the carotid artery and spinal cord in posterolaterally. Spinal cord and carotid artery were contoured as the organ at risk (OAR). The doses of the target volumes, the OAR volumes, the homogeneity index (HI) were compared.

Results: PTV parameters (Dmin, Dmean, Dmax, D90, D95) was compared in the 2 different technique.  IMRT in comparison to 3DCRT significantly reduced the high-dose volumes (V30, V35, V50) of carotid artery (p < 0.001), but not to the low dose volume (V10). CI was similar (0.9 vs. 0.9, p = 0.3) compared to 3DCRT. However, HI was significantly improved with IMRT (0.1 vs. 0.08, p < 0.001). The maximum dose of the spinal cord was lower in 3DCRT compared to IMRT (18 Gy vs. 44Gy).

Conclusion: IMRT is a superior radiotherapy (RT) technique in patients with T1/T2 glottic cancer in terms of protecting carotid artery.

Anahtar Kelimeler

• Radiotherapy,glottic cancer,carotid artery,3DCRT,IMRT

Erken Evre Glottik Larenks Kanserli Hastalarda Radyoterapi Tekniğinin Karotis Arter Dozu Üzerine Etkisi

Öz

Amaç: Bu çalışmanın amacı, erken evre glottik larenks kanser tanılı hastalarda iki radyoterapi tekniğinin karotis arter dozları açısından karşılaştırılmasıdır.

Gereç - Yöntemler: Bu çalışmaya, 10 erken evre (T1 / 2) glottik larenks kanser tanılı hastayı dahil ettik. Her bir hasta için hem yoğunluk ayarlı radyoterapi (YART) hem de 3 boyutlu konformal radyoterapi (3BKRT) tedavi planları hazırlandı. Tüm hastalar için tedavi volümleri (CTV, PTV) oluşturuldu. Tüm larinks, gerçek ve yalancı vokal kordlar, anterior-posterior komissürler, aritenoidler, aryepiglottik kıvrımlar, subglottik bölge dahil edilecek şekilde klinik hedef volüm (CTV) olşturuldu. Planlanan hedef volümü (PTV) oluşturmak için, tüm yönlerde CTV'ye 5 mm eklenirken, karotis arter ve spinal kordu korumak adına posterolateral yönde 3 mm'lik marj verildi. T1/T2 glottik kanserlerde lenfatik nodal metastaz riski çok düşük olduğu için, elektif nodal ışınlama yapılmadı. Spinal kord ve karotis arterler kritik organlar (OAR) olarak konturlandı. Hedef hacim dozları, OAR hacimleri, homojenlik indeksi (HI) karşılaştırıldı. Ek olarak, karotis arter için V30 <% 20, V10 <% 50 değerlendirildi ve spinal kordun maksimum dozu 45Gy ile sınırlandırıldı. Conformite indeksi (CI) hesaplandı. İstatistiksel analiz için Mann Whitney testi kullanıldı ve p <0.05 anlamlı kabul edildi.

Bulgular: PTV parametreleri (Dmin, Dmean, Dmax, D90, D95) iki farklı teknikte karşılaştırıldı. 3BKRT’ye kıyasla YART, karotis arterde yüksek doz hacimlerini (V30, V35, V50) belirgin olarak düşürürken (p < 0.001), düşük doz hacimleri (V10) her iki teknikte de yüksek seyretti. Her iki teknikte de CI benzer olup (0.9 vs. 0.9, p = 0.3), HI YART’de daha iyiydi (0.1 vs. 0.08, p < 0.001). Spinal kord maksimum dozları 3BKRT’de daha düşüktü (18 Gy vs. 44Gy).

Sonuç: IMRT, T1 / T2 glottik kanserli hastalarda karotis arterin korunması açısından üstün bir radyoterapi (RT) tekniğidir.

Anahtar Kelimeler

• Radyoterapi,Glottik kanser,Karotid arter,3BKRT,IMRT

Kaynakça

1. 1. Fitzmaurice C, Allen C, Barber RM, Barregard L, Bhutta ZA, Brenner H, et al. Global, regional, and national cancer incidence, mortality, years of life lost, years lived with disability, and disability-adjusted life-years for 32 cancer groups, 1990 to 2015: a systematic analysis for the global burden of disease study. 2017;3(4):524-48.
2. 2. Cantürk E, Topgül G, Gürler O, Tunç S, Abakay CD, Kurt M, et al. Evre I larinks kanseri tedavisinde 3 ve 5 Alan Yoğunluk Ayarlı Radyoterapi (3A-YART, 5A-YART) tekniklerinde karotis arterin dozimetrik olarak karşılaştırılması. 2017;19(3):141-6.
3. 3. Piccirillo JFJTL. Importance of comorbidity in head and neck cancer. 2000;110(4):593-602.
4. 4. Hoffman HT, Porter K, Karnell LH, Cooper JS, Weber RS, Langer CJ, et al. Laryngeal cancer in the United States: changes in demographics, patterns of care, and survival. 2006;116(S111):1-13.
5. 5. Waldfahrer F, Hauptmann B, Iro HJL-r-o. Lymph node metastasis of glottic laryngeal carcinoma. 2005;84(2):96-100.
6. 6. Marshak G, Brenner B, Shvero J, Shapira J, Ophir D, Hochman I, et al. Prognostic factors for local control of early glottic cancer: the Rabin Medical Center retrospective study on 207 patients. 1999;43(5):1009-13.
7. 7. Tamura Y, Tanaka S, Asato R, Hirano S, Yamashita M, Tamaki H, et al. Therapeutic outcomes of laryngeal cancer at Kyoto University Hospital for 10 years. 2007;127(sup557):62-5.
8. 8. Aaltonen L-M, Rautiainen N, Sellman J, Saarilahti K, Mäkitie A, Rihkanen H, et al. Voice quality after treatment of early vocal cord cancer: a randomized trial comparing laser surgery with radiation therapy. 2014;90(2):255-60.

9. 9. Matthiesen C, Herman TDLF, Singh H, Mascia A, Confer M, Simpson H, et al. Dosimetric and radiobiologic comparison of 3 D conformal, IMRT, VMAT and proton therapy for the treatment of early‐stage glottic cancer. 2015;59(2):221-8.
10. 10. Potters L, Gaspar LE, Kavanagh B, Galvin JM, Hartford AC, Hevezi JM, et al. American Society for Therapeutic Radiology and Oncology (ASTRO) and American College of Radiology (ACR) practice guidelines for image-guided radiation therapy (IGRT). 2010;76(2):319-25.
11. 11. Hartford AC, Galvin JM, Beyer DC, Eichler TJ, Ibbott GS, Kavanagh B, et al. American College of Radiology (ACR) and American Society for Radiation Oncology (ASTRO) practice guideline for intensity-modulated radiation therapy (IMRT). 2012;35(6):612-7.
12. 12. Chera BS, Amdur RJ, Morris CG, Mendenhall WMJIJoROBP. Carotid-sparing intensity-modulated radiotherapy for early-stage squamous cell carcinoma of the true vocal cord. 2010;77(5):1380-5.
13. 13. Chatterjee S, Guha S, Prasath S, Mallick I, Achari RJJocr, therapeutics. Carotid sparing hypofractionated tomotherapy in early glottic cancers: refining image guided IMRT to improve morbidity. 2013;9(3):452.
14. 14. Gomez D, Cahlon O, Mechalakos J, Lee NJRo. An investigation of intensity-modulated radiation therapy versus conventional two-dimensional and 3D-conformal radiation therapy for early stage larynx cancer. 2010;5(1):74.
15. 15. Tong C-C, Au K-H, Ngan RK-C, Cheung F-Y, Chow S-M, Fu Y-T, et al. Definitive radiotherapy for early stage glottic cancer by 6 MV photons. 2012;4(1):23.
16. 16. Khan MK, Koyfman SA, Hunter GK, Reddy CA, Saxton JPJRO. Definitive radiotherapy for early (T1-T2) glottic squamous cell carcinoma: a 20 year Cleveland Clinic experience. 2012;7(1):193.
17. 17. Camingue P, Christian R, Ng D, Williams P, Amin M, Roniger DLJMD. Comparison of external beam treatment techniques for T1-2, N0, M0 glottic cancers. 2012;37(2):221-4.
18. 18. Thomas E, Forbus WJAaop. Irradiation injury to the aorta and the lung. 1959;67(3):256.
19. 19. Crossen JR, Garwood D, Glatstein E, Neuwelt EAJJoCO. Neurobehavioral sequelae of cranial irradiation in adults: a review of radiation-induced encephalopathy. 1994;12(3):627-42.
20. 20. Huang TL, Hsu HC, Chen HC, Lin HC, Chien CY, Fang FM, et al. Long-term effects on carotid intima-media thickness after radiotherapy in patients with nasopharyngeal carcinoma. 2013;8(1):261.
21. 21. Gujral DM, Shah BN, Chahal NS, Bhattacharyya S, Hooper J, Senior R, et al. Carotid intima-medial thickness as a marker of radiation-induced carotid atherosclerosis. 2016;118(2):323-9.
22. 22. Gujral DM, Long M, Roe JW, Harrington KJ, Nutting CMJCO. Standardisation of Target Volume Delineation for Carotid-sparing Intensity-modulated Radiotherapy in Early Glottis Cancer. 2017;29(1):42-50.
23. 23. Osman S, Astreinidou E, Keskin-Cambay F, Breedveld S, de Boer H, Al-Mamgani A, et al. IMRT in image-guided single vocal cord irradiation. 2009;92:S67.
24. 24. Sert F, Karakoyun-Celik O, Esassolak MAJKbbidKJoe, nose, throat. Can carotid-sparing radiotherapy approaches replace with conventional techniques for the patients with T1 glottic larynx cancer? 2012;22(5):267-74.
25. 25. Osman SO, Astreinidou E, de Boer HC, Keskin-Cambay F, Breedveld S, Voet P, et al. IMRT for image-guided single vocal cord irradiation. 2012;82(2):989-97.
26. 26. Rosenthal DI, Fuller CD, Barker Jr JL, Mason B, Garcia JA, Lewin JS, et al. Simple carotid-sparing intensity-modulated radiotherapy technique and preliminary experience for T1–2 glottic cancer. 2010;77(2):455-61.