BACKGROUND AND PURPOSE: This study examined the efficacy of parotid gland sparing of three-dimensional conformal radiotherapy (3DCRT) compared with conventional radiotherapy for NPC patients. Both the dose given to the parotids and clinical assessment of dry mouth were conducted. MATERIALS AND METHODS: Dry mouth was assessed for 108 patients treated with conventional technique and 72 treated with 3DCRT. Dose analysis was performed in 48 patients of the 3DCRT group. A dose of 70 Gy was given to the midplane in conventional radiotherapy and to 90% isodose volume in 3DCRT. Prognostic factors affecting the severity of dry mouth were analyzed using Generalized Estimating Equation (GEE). RESULTS: In the 3DCRT group about 50% of the patients' parotid glands received less than 25 Gy. Parallel analysis of dry mouth shows a significant decrease in the incidence of severe xerostomia after 3DCRT. The proportion of patients without dry mouth was also significantly higher in the 3DCRT group than the conventional group at 1-3 years after completion of radiotherapy. Although 3DCRT delivered a higher dose to the tumor, it spared the parotid gland significantly better than the conventional treatment. Late toxicities were mostly similar between the 2 groups while local control in T4 patients and survival were improved for 3DCRT. CONCLUSION: Dosimetrically and clinically 3DCRT is better than conventional technique regarding parotid gland protection.
BACKGROUND AND PURPOSE: This study examined the efficacy of parotid gland sparing of three-dimensional conformal radiotherapy (3DCRT) compared with conventional radiotherapy for NPCpatients. Both the dose given to the parotids and clinical assessment of dry mouth were conducted. MATERIALS AND METHODS:Dry mouth was assessed for 108 patients treated with conventional technique and 72 treated with 3DCRT. Dose analysis was performed in 48 patients of the 3DCRT group. A dose of 70 Gy was given to the midplane in conventional radiotherapy and to 90% isodose volume in 3DCRT. Prognostic factors affecting the severity of dry mouth were analyzed using Generalized Estimating Equation (GEE). RESULTS: In the 3DCRT group about 50% of the patients' parotid glands received less than 25 Gy. Parallel analysis of dry mouth shows a significant decrease in the incidence of severe xerostomia after 3DCRT. The proportion of patients without dry mouth was also significantly higher in the 3DCRT group than the conventional group at 1-3 years after completion of radiotherapy. Although 3DCRT delivered a higher dose to the tumor, it spared the parotid gland significantly better than the conventional treatment. Late toxicities were mostly similar between the 2 groups while local control in T4 patients and survival were improved for 3DCRT. CONCLUSION: Dosimetrically and clinically 3DCRT is better than conventional technique regarding parotid gland protection.
Authors: S B Jensen; A M L Pedersen; A Vissink; E Andersen; C G Brown; A N Davies; J Dutilh; J S Fulton; L Jankovic; N N F Lopes; A L S Mello; L V Muniz; C A Murdoch-Kinch; R G Nair; J J Napeñas; A Nogueira-Rodrigues; D Saunders; B Stirling; I von Bültzingslöwen; D S Weikel; L S Elting; F K L Spijkervet; M T Brennan Journal: Support Care Cancer Date: 2010-03-17 Impact factor: 3.603
Authors: Sung Ho Moon; Kwan Ho Cho; Chang-Geol Lee; Ki Chang Keum; Yeon-Sil Kim; Hong-Gyun Wu; Jin Ho Kim; Yong Chan Ahn; Dongryul Oh; Jong Hoon Lee Journal: Strahlenther Onkol Date: 2016-03-14 Impact factor: 3.621
Authors: L Jang-Chun; H Jing-Min; J Yee-Min; L Dai-Wei; C Chang-Ming; L Chun-Shu; H Wen-Yen; S Yu-Fu; L Kuen-Tze; F Chao-Yueh; L Cheng-Hsiang; C Hsing-Lung Journal: Acta Otorhinolaryngol Ital Date: 2014-08 Impact factor: 2.124