Wong Wai-Lup, Gibson Daren, Sanghera Bal, Goodchild Kate, Saunders Michele
Paul Strickland Scanner Centre, Mount Vernon Hospital, Northwood, Middlesex, UK.
Nucl Med Commun. 2007 Sep;28(9):675-80. doi: 10.1097/MNM.0b013e32829152b1.
The aims of the study were to (1) evaluate the range of physiological FDG uptake in normal pharyngeal palatine tonsil, and (2) investigate the possibility of establishing a cut-off threshold to distinguish between normal pharyngeal palatine tonsil FDG uptake from occult pharyngeal palatine tonsil primary cancer.
FDG PET CT of 43 consecutive patients with a low risk of head and neck cancer were reviewed by two observers. Axial PET CT was used to identify foci of FDG uptake related to the pharyngeal palatine tonsil. The highest standardized uptake value, SUVmax, of the left and right pharyngeal palatine tonsil was calculated. Similar analysis was performed on 10 consecutive patents with histologically proven occult pharyngeal palatine tonsil primary cancer.
The mean SUVmax of the 43 right pharyngeal palatine tonsils was 4.82 (range, 1.16-12.74) and 4.68 (range, 0.88-13.65) for the 43 left pharyngeal palatine tonsils with no statistical difference observed (P=0.4). Normal pharyngeal palatine tonsil uptake was generally symmetrical and there was a positive correlation between SUVmax from the left and right sides which was statistically significant (r=0.9, P<0.0001). In the same patient the difference in SUVmax between left and right pharyngeal palatine tonsil ranged from 0.01 to 2.66 and patients with occult pharyngeal palatine tonsil primary cancer it ranged from 0.85 to 11.08. ROC analysis showed that an 'SUVmax difference' cut-off of 0.83 would achieve a sensitivity of 100% and specificity of 81% for detecting occult pharyngeal palatine tonsil primary cancers.
There is considerable variation of pharyngeal palatine tonsil FDG uptake in patients with no pharyngeal palatine tonsil primary cancer. However, in the same patient there is generally only a small difference in uptake between left and right sides. The absolute difference in SUVmax between left and right pharyngeal palatine tonsil is a potentially useful parameter for distinguishing between normal FDG uptake in pharyngeal palatine tonsil from occult pharyngeal palatine tonsil primary cancer.
本研究的目的是（1）评估正常咽腭扁桃体生理性氟代脱氧葡萄糖（FDG）摄取范围，以及（2）研究建立一个截断阈值以区分正常咽腭扁桃体FDG摄取与隐匿性咽腭扁桃体原发性癌的可能性。
两名观察者对43例头颈部癌症低风险的连续患者的FDG PET CT进行了回顾。使用轴向PET CT识别与咽腭扁桃体相关的FDG摄取灶。计算左右咽腭扁桃体的最高标准化摄取值（SUVmax）。对10例经组织学证实为隐匿性咽腭扁桃体原发性癌的连续患者进行了类似分析。
43个右侧咽腭扁桃体的平均SUVmax为4.82（范围1.16 - 12.74），43个左侧咽腭扁桃体的平均SUVmax为4.68（范围0.88 - 13.65），未观察到统计学差异（P = 0.4）。正常咽腭扁桃体摄取通常是对称的，左右两侧的SUVmax之间存在正相关，具有统计学意义（r = 0.9，P < 0.0001）。在同一患者中，左右咽腭扁桃体的SUVmax差异范围为0.01至2.66，在隐匿性咽腭扁桃体原发性癌患者中，差异范围为0.85至11.08。ROC分析表明，“SUVmax差异”截断值为0.83时，检测隐匿性咽腭扁桃体原发性癌的敏感性为100%，特异性为81%。
无咽腭扁桃体原发性癌患者的咽腭扁桃体FDG摄取存在相当大的差异。然而，在同一患者中，左右两侧的摄取通常仅有微小差异。左右咽腭扁桃体SUVmax的绝对差异是区分咽腭扁桃体正常FDG摄取与隐匿性咽腭扁桃体原发性癌的一个潜在有用参数。
