根據衛生署的統計資料顯示，鼻咽癌（nasopharyngeal carcinoma，NPC）在1997 年的國人癌症死亡原因排名為第九名，而2007年的排名已掉到11 名，由此可見台灣在治療鼻咽癌的技術方面已有顯著的進步。鼻咽癌發生位置為鼻咽腔（nasopharynx），位於咽喉的上端及鼻腔正後方之區域，屬於呼吸道之區域。由於鼻咽腔位置處於頭顱較深處，故一旦發生病變時通常難以自我察覺，必須藉助鼻咽內視鏡等來檢查。主要的致病因素大致上分三類，第一是種族遺傳因素，我們發現中國南方人發生鼻咽癌的機率比高加索人高出25 倍，HLA 基因型為A2/B64、A33/B58 的罹患率也比常人高出2 到3 倍，第二是飲食因素，在香港的研究指出，常食用醃製類食物的人，發生鼻咽癌的機率也會上升，最後則是病毒感染，早期的研究結果已證明鼻咽癌的患者，其腫瘤組織切片中發現大量的EB 病毒。在放射治療方面，針對鼻咽癌所用的技術以強度調控放射治療(IMRT)與近接治療（Brachytherapy）為主。本研究試圖比較這兩種技術對鼻咽癌患者的療效，以得到單一且有力的結論。

According to the Department of Health's statistical data demonstration，nasopharyngeal carcinoma (nasopharyngeal carcinoma, NPC) in 1997 cause of people death at ninth grade in Taiwan. But in 2007 place has fallen to 11，Thus it can be seen Taiwan is treating pharyngeal cancer's technical aspect to have the remarkable progress。The nasopharyngeal carcinogenesis position is the nose pharyngeal cavity (nasopharynx)，Located at pharynx and larynx's upper extreme and nasal cavity rear area region，Belongs
to region of the respiratory tract。Because the nose pharyngeal cavity position is in the head to compare the deep place, therefore, once has time the pathological change usually realized with difficulty, must and
so on inspect with the aid of the nasopharyngeal endoscope.The main pathogenic factor is divided three kinds roughly, first is the racial inheritance factor, we discovered that the Chinese southerners have pharyngeal cancer's probability to be higher than 25 times compared to the Caucasus person, the HLA genotype are A2/B64, A33/B58 suffer from rate are also higher than compared to the average man 2 to 3 times, second is the diet factor, pointed out in Hong Kong's research, often the edible souse class food's person, will have pharyngeal cancer's probability also to rise, finally will be the virus infection, the early findings had proven that pharyngeal cancer's patient, in its tumor tissue slice will discover the massive EB virus.
In the radiotherapy aspect, the technology which uses in view of pharyngeal cancer and treats (Brachytherapy) recently received by intensity regulation radiotherapy (IMRT) primarily.This research attempts to compare these two kind of technologies to pharyngeal cancer patient's curative effect, by obtains sole and the powerful conclusion