Cheung Y K, Sham J, Cheung Y L, Chan F L
Department of Diagnostic Radiology, University of Hong Kong, Queen Mary Hospital, Pokfulam.
Oncology. 1994 Jan-Feb;51(1):42-6. doi: 10.1159/000227308.
Over a period of 16 months, a total of 175 patients with newly diagnosed nasopharyngeal carcinoma (NPC) were evaluated with plain radiography and computed tomography (CT) of nasopharynx and base of skull. 54 of 175 patients (30.9%) had CT evidence of skull base erosion. Plain radiography failed to demonstrate the skull base erosion in 22 of 54 patients (40.7%) and underestimated the extent of bony involvement in another 21 patients (38.9%). In 14 of 54 patients (25.9%), there was also false suspicion of bony erosion in the plain films in one or more regions of the skull base which was not substantiated by CT and subsequent clinical course. The present study shows that plain radiography lacks sensitivity and specificity in detecting skull base erosion by NPC. CT evaluation of NPC patients should include thin CT sections of base of skull for detection of subtle bone erosion, and this would allow better decision concerning the shielding of the pituitary-hypothalamic axis during radiotherapy for improvement in therapeutic ratio. For the investigation of individuals highly suspicious of harboring NPC, even when the plain radiography is negative, CT should still be performed as this may give the only clue to the presence of a small submucosally spreading NPC.
在16个月的时间里，对175例新诊断的鼻咽癌（NPC）患者进行了鼻咽部及颅底的X线平片和计算机断层扫描（CT）评估。175例患者中有54例（30.9%）有颅底骨质侵蚀的CT证据。X线平片未能显示54例患者中22例（40.7%）的颅底骨质侵蚀，并且低估了另外21例患者（38.9%）的骨质受累范围。在54例患者中的14例（25.9%），X线平片在颅底的一个或多个区域也存在对骨质侵蚀的假阳性怀疑，而CT及后续临床病程并未证实。本研究表明，X线平片在检测NPC引起的颅底骨质侵蚀方面缺乏敏感性和特异性。对NPC患者进行CT评估时应包括颅底的薄层CT扫描以检测细微的骨质侵蚀，这将有助于在放疗期间更好地决定垂体-下丘脑轴的屏蔽，以提高治疗比。对于高度怀疑患有NPC的个体进行检查时，即使X线平片为阴性，仍应进行CT检查，因为这可能是存在黏膜下小范围扩散的NPC的唯一线索。
