Sakata K, Hareyama M, Tamakawa M, Oouchi A, Sido M, Nagakura H, Akiba H, Koito K, Himi T, Asakura K
Department of Radiology, Sapporo Medical University, School of Medicine, Japan.
Int J Radiat Oncol Biol Phys. 1999 Jan 15;43(2):273-8. doi: 10.1016/s0360-3016(98)00417-9.
To examine the usefulness of MR imaging for predicting local control of nasopharyngeal carcinoma (NPC) and the value of MR imaging in the newly published fifth edition of the TNM classification.
We studied 29 patients with NPC with MR imaging and CT before and after treatment. Staging was done according to the fourth and newly published fifth editions of the International Union Against Cancer (UICC) staging system. The radiotherapy protocol was designed to deliver 66 to 68 Gy to the primary tumor and clinically involved nodes.
MR proved better than CT at identifying obliteration of the pharyngobasilar fascia, invasion of the sinus of Morgagni, through which the cartilaginous portion of the eustachian tube and the levator veli palatini muscle pass, invasion of the skull base, and metastases to lymph nodes in the carotid and retropharyngeal spaces. All seven patients without invasion of the pharyngobasilar fascia had local control. The local control rates of patients with invasion of the skull base were not good (60 to 73%). There was no apparent relationship between tumor volume determined by T1-weighted MR images and local control when the tumor volume was more than 20 cc. The newly published N staging system appears to successfully identify the high-risk group for distant metastasis as N3. In our series, four of five patients with N3 disease developed distant metastases.
Deep infiltration of the tumor is a more important prognostic factor in NPC than tumor volume. Since the newly published T staging system requires a search for tumor invasion into soft tissue such as parapharyngeal space and bony structures, MR imaging may be indispensable for the newly published NPC staging system.
探讨磁共振成像（MR）对预测鼻咽癌（NPC）局部控制情况的作用以及MR成像在新发布的第五版TNM分类中的价值。
我们对29例NPC患者在治疗前后进行了MR成像和CT检查。根据国际抗癌联盟（UICC）分期系统的第四版及新发布的第五版进行分期。放疗方案设计为对原发肿瘤及临床受累淋巴结给予66至68 Gy的剂量。
在识别咽颅底筋膜消失、咽鼓管软骨部和腭帆提肌通过的莫尔加尼窦侵犯、颅底侵犯以及颈动脉间隙和咽后间隙淋巴结转移方面，MR比CT表现更好。所有7例未侵犯咽颅底筋膜的患者均实现了局部控制。颅底侵犯患者的局部控制率不佳（60%至73%）。当肿瘤体积超过20 cc时，T1加权MR图像所确定的肿瘤体积与局部控制之间无明显关系。新发布的N分期系统似乎成功地将远处转移的高危组识别为N3。在我们的系列研究中，5例N3期患者中有4例发生了远处转移。
肿瘤的深度浸润在NPC中是比肿瘤体积更重要的预后因素。由于新发布的T分期系统要求寻找肿瘤对诸如咽旁间隙和骨结构等软组织的侵犯，MR成像对于新发布的NPC分期系统可能是不可或缺的。
