摘要
目的：分析经改用面颈联合野后的迟发性反应状况及原因，并提出改进常规放疗技术的一些建议。方法：收集1997年3月至2006年3月初治鼻咽癌206例资料。患者给予60Co或6MV—X线放疗，第一阶段采用面颈联合野＋下颈前切野，第二阶段耳前野＋颈前大切线野照射，第三阶段再次缩小耳前野，颈部行深部x线小野照射至根治剂量。受损器官或组织的迟发性反应参照RTOG／EORTC的SOMA分级标准判断。结果：全组206例鼻咽癌患者出现不同程度的唾液腺损伤，且不可逆转。颈部软组织的迟发性反应检出率85．9％。后组颅神经损伤44例，占颅神经损伤的84．6％。结论：面颈联合野二野照射方法，其高剂量区分布于两侧的颞底部、颞颔关节、腮腺、颈部Ⅱ区软组织等处；颈前大切线野，其上界与耳前野的后下角相重叠，使该区照射剂量过高。两者是造成鼻咽癌常规放疗迟发性反应发生率仍较高的基本原因。鼻前面颈联合野三野照射方法可明显改善剂量分布。
Objective： To analyze the state and cause of late response after radiotherapy with lateral opposing facio-cervical fields in nasopharyngeal carcinoma patients, and to propose some suggestions to improve the conventional radiation. Methods： We reviewed 206 patients with nasopharyngeal carcinoma who received 6MV-X ray or Co60 radiotherapy between March 1997 and March 2006. The radiotherapy was the initial treatment for all of these patients. In the first stage of radiotherapy, two lateral opposing facio-cervical fields and the inferi- or-cervical-supraclavicular field were used. In the second stage of radiotherapy, pre-auricular portals and whole neck anterior tangential portal were used. At the third stage, shrinking field technique was employed in pre-auricular portals, and deep X-ray was delivered for neck radiation. The late injuries of radiotherapy to body organs and tissues were evaluated according to SOMA of RTOG/EORTC criterion. Results： All patients have different degrees of irreversible damage in the salivary glands. The late response rate of cervical soft tissue was 85.9%. Forty-four cases had injuries in the lower last four cranial nerves （counting for 84.6% of cranial nerve injury）. Conclusion： In conventional radiotherapy covering bilateral opposing facio-cervical fields, the high-dose-distribution area included the lower part of temporal lobe, temporomandibular joint, parotid glands and soft tissue of neck area 1] etc. The overlapping between whole neck tangential portal and posterior-inferior part of pre-auricular portal results in radiation with a higher dose in this area. The above reasons are the main cause of high rate of late response after conventional radiotherapy in nasopharyngeal carcinoma patients. Application of radiation technique covering anterior facio-cervical fields may significantly improve the dose distribution.
出处
《中国肿瘤临床》
CAS
CSCD
北大核心
2009年第4期192-194,198,共4页
Chinese Journal of Clinical Oncology
关键词
鼻咽肿瘤
放射疗法
迟发反应
Nasopharyngeal carcinoma
Radiotherapy
Late response
