Portaluri Maurizio, Fucilli Fulvio I M, Castagna Roberta, Bambace Santa, Pili Giorgio, Tramacere Francesco, Russo Donatella, Francavilla Maria Carmen
Department of Radiotherapy, AUSL Br-1, Di Summa-Perrino Hospital, Brindisi, Italy.
Int J Radiat Oncol Biol Phys. 2006 Nov 15;66(4):1036-43. doi: 10.1016/j.ijrobp.2006.03.014. Epub 2006 Jun 5.
To evaluate the dosimetric parameters of three-dimensional conformal radiotherapy (3D-CRT) in locally advanced head-and-neck tumors (Stage II and above) and the effects on xerostomia.
A total of 49 patients with histologically proven squamous cell cancer of the head and neck were consecutively treated with 3D-CRT using a one-point setup technique; 17 had larynx cancer, 12 oropharynx, 12 oral cavity, and 6 nasopharynx cancer; 2 had other sites of cancer. Of the 49 patients, 41 received postoperative RT and 8 definitive treatment. Also, 13 were treated with cisplatin-based chemotherapy before and during RT; in 6 cases, 5-fluorouracil was added. The follow-up time was 484-567 days (median, 530 days).
One-point setup can deliver 96% of the prescribed dose to the isocenter, to the whole planning target volume, including all node levels of the neck and without overdosages. The mean dose to the primary planning target volume was 49.54 +/- 4.82 Gy (51.53 +/- 5.47 Gy for larynx cases). The average dose to the contralateral parotid gland was approximately 38 Gy (30 Gy for larynx cases). The maximal dose to the spinal cord was 46 Gy. A Grade 0 Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer xerostomia score corresponded to a mean dose of 30 Gy to one parotid gland. A lower xerostomia score with a lower mean parotid dose and longer follow-up seemed to give rise to a sort of functional recovery phenomenon.
Three dimensional-CRT in head-and-neck cancers permits good coverage of the planning target volume with about 10-11 segments and one isocenter. With a mean dose of approximately 30 Gy to the contralateral parotid, we observed no or mild xerostomia.
评估三维适形放疗（3D-CRT）在局部晚期头颈肿瘤（II期及以上）中的剂量学参数及其对口干症的影响。
49例经组织学证实的头颈鳞状细胞癌患者采用单点设置技术连续接受3D-CRT治疗；其中17例为喉癌，12例为口咽癌，12例为口腔癌，6例为鼻咽癌；2例为其他部位癌症。49例患者中，41例接受术后放疗，8例接受根治性治疗。此外，13例在放疗前及放疗期间接受了以顺铂为基础的化疗；6例加用了5-氟尿嘧啶。随访时间为484-567天（中位时间为530天）。
单点设置可将规定剂量的96%输送至等中心，输送至整个计划靶区，包括颈部所有淋巴结水平，且无过量照射。原发计划靶区的平均剂量为49.54±4.82 Gy（喉癌病例为51.53±5.47 Gy）。对侧腮腺的平均剂量约为38 Gy（喉癌病例为30 Gy）。脊髓的最大剂量为46 Gy。放射治疗肿瘤学组/欧洲癌症研究与治疗组织口干症评分为0级对应的一侧腮腺平均剂量为30 Gy。口干症评分较低、腮腺平均剂量较低且随访时间较长似乎会产生某种功能恢复现象。
头颈癌的三维适形放疗通过约10-11个射野和一个等中心可实现对计划靶区的良好覆盖。对侧腮腺平均剂量约为30 Gy时，我们观察到无口干症或仅有轻度口干症。
