基于磁共振成像的鼻咽癌颅底骨质破坏的预后分析

Prognostic Analysis of Skull-base Invasion of Nasopharyngeal Carcinoma Based on Magnetic Resonance Imaging

【目的】探讨基于磁共振成像(MRI)的鼻咽癌颅底骨质破坏的预后价值。【方法】于2003年至2004年共924例经病理等确诊为无远处转移的鼻咽初治病人纳入本研究,所有的病人均在治疗前进行了MRI检查并以放疗为首要治疗手段。我们回顾性的分析了相应的MRI及病历资料。所有的924例病人、MRI证实有颅底骨质破坏的病人、315例T3分期的的病人及227例T2分期的病人被分别挑选出来进行预后分析。分期依据美国癌症分期联合委员会(AJCC)第六版鼻咽癌分期标准。【结果】MRI下颅底骨质破坏的发生率约为55.4%。颅底骨质破坏并非影响鼻咽癌患者总生存(OS)和无远处转移生存(DMFS)的独立预后因素,但有可能是影响无局部复发生存(LRFS)的独立预后因素(P=0.068)。对于512例合并颅底骨质破坏的患者及315例T3分期的患者,根据受侵部位进行的颅底骨质破坏分级是影响其OS(P=0.002及P=0.005)及DMFS(P值均为0.001)的独立预后因素。MRI下严重级别的颅底骨质破坏是影响鼻咽癌患者OS及DMFS的独立预后因素(P值均小于0.001)。合并轻度级别颅底骨质破坏的T3分期患者与T2a分期的患者在预后方面(OS、LRFS及DMFS)的差异没有统计学意义。【结论】MRI下的颅底骨质破坏并非鼻咽癌患者的独立预后因素;然而,根据受侵部位的严重级别的颅底骨质破坏具有阳性的预后价值。

【Objective】 To evaluate the prognostic value of skull-base invasion of nasopharyngeal carcinoma （NPC） based on magnetic resonance imaging （MRI）. 【Methods】 A total of 924 patients who were diagnosed with NPC between 2003 and 2004, had undergone MRI scan and received radiotherapy as their primary treatment, and had no distant metastasis were included in this study. MRI images and medical records were analyzed retrospectively. All the 924 cases, patients who developed skull-base invasions based on MRI, 315 patients with T3 disease and 227 patients with T2 disease were selected for analysis. The staging was according to the sixth edition of the American Joint Commission on Cancer （AJCC） staging system. 【Results】 Incidence of skull- base invasion according to MRI was 55.4%. Of 924 cases, skull-base invasion on MRI was not an independent prognostic factor for overall survival （OS） and distant metastasis-free survival （DMFS）, but was a marginally significant independent prognostic factor for local relapse-free survival （LRFS）, P = 0.068. Grading of MRI-detected skull-base erosion according to the site of invasion was an independent prognostic factor for OS （P = 0.002 and P = 0.005） and DMFS （P = 0.001 for both） in the 512 patients with skull-base invasions and 315 patients with T3 disease. Severe-grade of skull-base invasion on MRI was an independent prognostic factor for OS and DMFS in the 924 patients （P〈0.001 for both）. No significant differences were observed on OS, LRFS, and DMFS between T2a patients and T3 patients with low-grade of MRI-detected skull-base involvement.【Conclusions】 Skull-base invasion based on MRI is not an independent prognostic factor for NPC. However, severe-grade of invasion according to the site of involvement has positive prognostic value.