Intensity-modulated radiation therapy reduces late salivary toxicity and mandibular osteoradionecrosis in the treatment of oral cavity cancer: Retrospective study

Abstract

Aim: It is increasingly being recognized that oral cavity cancer incidences are rising globally. Irradiation using 3D conformal radiotherapy results in high incidence of late radiation side-effects. Xerostomia and manibudlar osteoradionecrosis result in most significant effects on patients quality of life. Intensive modulated radiotherapy (IMRT) is an advanced approach to 3D treatment planning and conformal radiotherapy. It optimizes the delivery of irradiation to irregularly-shaped volumes and has the ability to spare normal tissue while delivering adequate doses to the tumor volumes. In present retrospective analysis, we aimed to analyze the clinical and dosimetric characteristics with the dose constraints in patients followed for oral cavity cancer and treated by IMRT.

Methods: 19 patients followed for non-metastatic oral cavity cancer who were treated with IMRT, were retrospectively analyzed at the radiotherapy department Hassan II University hospital, Fes, Morocco between January 2016 and December 2016.

Results: The mean age was 58.5 years. The predominant histological type was epidermoid carcinoma. RCC was received in 79% of cases versus 15.8% of exclusive radiotherapy. 68.4% of cases received 70Gy for HR PTV, the mean dose delivered to the homolateral and controlateral parotid glands was 36Gy and 22Gy respectively, the average dose delivered to the mandible was 51.9Gy.

Conclusion: IMRT of oral cavity tumors offers reduces the risks of xerostomia and ORN through parotid and mandibular sparing, without compromising on target volume coverage.

Keywords

• Intensive modulated radiotherapy,Oral cavity cancer,Xerostomia,Mandibular osteoradionecrosis

Şiddet modülasyonlu radyasyon tedavisi, oral kavite kanseri tedavisinde geç tükrük toksisitesini ve mandibular osteoradionekrozu azaltır: Retrospektif çalışma

Öz

Amaç: Dünyada oral kavite kanseri vakalarının giderek arttığı artan bir şekilde bilinmektedir. 3D konformal radyoterapi kullanılarak ışınlama, geç radyasyon yan etkilerinin yüksek insidansına neden olur. Xerostomia ve manibudlar osteoradiyonekroz, hastaların yaşam kalitesi üzerinde en önemli etkilerle sonuçlanır. Yoğun modüle radyoterapi (IMRT), 3D tedavi planlaması ve konformal radyoterapiye ileri bir yaklaşımdır. İrradyasyonun düzensiz şekilli hacimlere ulaştırılmasını optimize eder ve tümör hacimlerine yeterli dozları verirken normal dokuları yedekleme özelliğine sahiptir. Bu retrospektif analizde, oral kavite kanseri için takip edilen ve IMRT ile tedavi edilen hastalarda doz kısıtları ile klinik ve dozimetrik özellikleri analiz etmeyi amaçladık.

Yöntemler: IMRT ile tedavi edilen metastatik olmayan oral kavite kanseri nedeniyle takip edilen 19 hasta retrospektif olarak Ocak 2016-Aralık 2016 tarihleri arasında Fes, Fas'taki radyoterapi bölümü II’de kayıt edildi.

Bulgular: Ortalama yaş 58,5 idi. Baskın histolojik tip epidermoid karsinomdu. Olguların %79'unda RCC, %15.8'inde özel radyoterapi görüldü. Olguların %68,4'ünde HR PTV için 70Gy, homolateral ve kontrolateral parotis bezlerine verilen ortalama doz sırasıyla 36Gy ve 22Gy, mandibula verilen ortalama doz 51,9Gy idi.

Sonuç: Oral kavite tümörlerinin IMRT'si, hedef hacim kapsamından ödün vermeden, parotis ve mandibular koruma ile kserostomi ve ORN riskini azaltmaktadır.

Anahtar Kelimeler

• Yoğun modüle radyoterapi,Oral kavite kanseri,Kserostomi,Mandibular osteoradionekroz

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