State Key Laboratory of Oncology in South China, Guangzhou, Guangdong, People's Republic of China.
Am J Clin Oncol. 2010 Dec;33(6):604-8. doi: 10.1097/COC.0b013e3181c4c6c7.
In 2-dimensional radiotherapy, the irradiating portal is defined mainly by soft tissues and bony structures, so the exact location of nasopharyngeal tumors and many spatial relationships are unknown, resulting in high local-regional relapse rates and radiation toxicities. Three-dimensional conformal radiotherapy (3D CRT) provides more precise targeting of radiation. We studied whether 3D CRT could maintain survival and increase local-regional tumor control whereas reducing the morbidity and severity of radiation toxicity in patients with early primary nasopharyngeal carcinoma (NPC).
Patients with histologically proven keratinizing or nonkeratinizing undifferentiated NPC (T₁₋₂N₀₋₁M₀ stage) received a prescribed 3D CRT dose of 70 Gy to the gross tumor volume (GTV(nx)), 60 Gy to the GTV(nx) with an additional 5- to 10-mm margin (CTV(nx)₆₀), 60 to 70 Gy to the region involved by the metastatic lymph nodes (GTV(nd)), and 50 Gy to the prophylactic irradiating region (CTV(nd)₅₀).
Of 58 patients enrolled between August 2001 and December 2006, (48 men; median age, 46 years; range, 29-69 years), 15 had stage I and 43 had stage II disease. At 5 years, overall survival was 95% and disease-free survival was 91%; 93% of patients were free of local-regional recurrence and 98% were free of distant metastases. Grade 2 or 3 xerostomia occurred in 7 patients and trismus occurred in 5. Mean standard deviation (SD) dental gap was 37.4 (6.9) mm. Four patients had recurrent lesions, mainly in-field.
The survival and morbidity provided by 3D CRT were excellent in these patients with early NPC.
在二维放疗中，照射野主要由软组织和骨结构定义，因此鼻咽肿瘤的确切位置和许多空间关系未知，导致局部区域复发率和放射性毒性高。三维适形放疗（3D CRT）提供了更精确的放疗靶向。我们研究了 3D CRT 是否可以在保持生存和提高局部肿瘤控制率的同时，降低早期原发性鼻咽癌（NPC）患者的发病率和放射性毒性的严重程度。
经组织学证实的角化或非角化未分化 NPC（T₁₋₂N₀₋₁M₀ 期）患者接受了规定的 3D CRT 剂量，GTV(nx) 为 70 Gy，GTV(nx) 加 5-10 mm 边界为 60 Gy（CTV(nx)₆₀），转移性淋巴结受累区域为 60-70 Gy（GTV(nd)），预防照射区域为 50 Gy（CTV(nd)₅₀）。
2001 年 8 月至 2006 年 12 月期间共纳入 58 例患者，其中男 48 例，中位年龄 46 岁（范围 29-69 岁），15 例为Ⅰ期，43 例为Ⅱ期。5 年总生存率为 95%，无病生存率为 91%；93%的患者无局部区域复发，98%的患者无远处转移。7 例患者出现 2 级或 3 级口干，5 例患者出现张口困难。平均标准偏差（SD）牙间隙为 37.4（6.9）mm。4 例患者出现复发病灶，主要在靶区内。
3D CRT 为这些早期 NPC 患者提供的生存率和发病率非常优异。
