State Key Laboratory of Oncology in Southern China, Guangzhou, People's Republic of China.
Int J Radiat Oncol Biol Phys. 2012 Jan 1;82(1):327-33. doi: 10.1016/j.ijrobp.2010.09.011. Epub 2010 Oct 29.
Reports of intensity-modulated radiotherapy (IMRT) for early-stage nasopharyngeal carcinoma (NPC) have been limited. The present study evaluated the long-term survival outcomes and toxicity of early-stage NPC patients treated with IMRT alone.
Between February 2001 and January 2008, 198 early-stage (T1-T2bN0-N1M0) NPC patients had undergone IMRT alone. The data from these patients were retrospectively analyzed. The patients were treated to 68 Gy at 2.27 Gy/fraction prescribed to the planning target volume of the primary nasopharygeal gross tumor volume. The Radiation Therapy Oncology Group scoring system was used to assess the toxicity.
At a median follow-up of 50.9 months (range, 12-104), the 5-year estimated disease-specific survival, local recurrence-free survival, and distant metastasis-free survival rate was 97.3%, 97.7%, and 97.8%, respectively. The 5-year local recurrence-free survival rate was 100% for those with Stage T1 and T2a and 94.2% for those with Stage T2b lesions (p = 0.252). The 5-year distant metastasis-free survival rate for Stage T1N0, T2N0, T1N1, and T2N1 patients was 100%, 98.8%, 100%, and 93.8%, respectively (p = .073). All local recurrence occurred in patients with T2b lesions. Five patients developed distant metastasis. Of these 5 patients, 4 had had Stage T2bN1 disease and 1 had had Stage T2bN0 disease with retropharyngeal lymph node involvement. The most common acute toxicities were mainly Grade 1 or 2. At 24 months after IMRT, no Grade 3 or 4 xerostomia had developed, and 62 (96.9%) of 64 evaluated patients were free of trismus; only 2 patients (3.1%) had Grade 1 trismus. Radiation encephalopathy and cranial nerve injury were not observed.
IMRT alone for Stage T1N0, T2N0, T1N1, and T2N1 yielded satisfactory survival outcomes with acceptable toxicity, and no differences were found in survival outcomes among these four subgroups. Patients with Stage T2b lesions might have relatively greater risk of local recurrence and those with T2bN1 disease mighth have a greater risk of distant metastasis.
调强放疗（IMRT）治疗早期鼻咽癌（NPC）的报道有限。本研究评估了单纯接受 IMRT 治疗的早期 NPC 患者的长期生存结果和毒性。
2001 年 2 月至 2008 年 1 月，198 例早期（T1-T2bN0-N1M0）NPC 患者接受单纯 IMRT 治疗。回顾性分析这些患者的数据。患者接受 68 Gy 的治疗，每次 2.27 Gy，处方剂量为鼻咽原发肿瘤大体肿瘤体积的计划靶区。采用放射治疗肿瘤学组评分系统评估毒性。
中位随访 50.9 个月（范围，12-104），5 年估计疾病特异性生存率、局部无复发生存率和远处无转移生存率分别为 97.3%、97.7%和 97.8%。T1 和 T2a 期患者的 5 年局部无复发生存率为 100%，T2b 期患者为 94.2%（p=0.252）。T1N0、T2N0、T1N1 和 T2N1 期患者的 5 年远处无转移生存率分别为 100%、98.8%、100%和 93.8%（p=0.073）。所有局部复发均发生在 T2b 期患者中。5 例发生远处转移。其中 4 例为 T2bN1 期，1 例为 T2bN0 期，伴有咽后淋巴结受累。最常见的急性毒性主要为 1 级或 2 级。在 IMRT 后 24 个月时，没有发生 3 级或 4 级口干症，64 例评估患者中有 62 例（96.9%）无张口受限；仅有 2 例（3.1%）为 1 级张口受限。未观察到放射性脑病和颅神经损伤。
T1N0、T2N0、T1N1 和 T2N1 期患者单纯接受 IMRT 治疗可获得满意的生存结果，且毒性可接受，这四个亚组之间的生存结果无差异。T2b 期病变患者局部复发风险相对较高，T2bN1 期患者远处转移风险较高。
