Cervical Lymph Node Metastases In Patients With Carcinoma Of The Oropharynx: Diagnostic Value And Guidance For Surgical Treatment Selected Of Palpation, US, MRI And US/MRI

Objective:To compare the diagnostic accuracy of palpation, ultrasonic diagnosis(US),and magnetic resonance imaging(MRI) in the preoperative detection of cervical lymph node metastases from patients with carcinoma of the oropharynx per level(ⅠthroughⅤ),and to provide the scientific theoretical basis to the reasonable surgical treatment for the cervical region in patients with carcinoma of the oropharynx.Material and methods:From July 2008 to December 2008,twenty patients with carcinoma of the oropharynx in Xiangya hospital who wound have neck dissection throughⅠtoⅤunderwent palpation,US,and MRI.The results of each modality were analyzed for sensitivity, specificity,false-positive rate,false-negative rate and accuracy. Pathologic analysis of the surgical resection served as the reference standard.The palpation,US,MRI and US/MRI were compared for specificity,sensitivity and accuracy with Chi-square test or Fisher's exact test,and we discussed the value of palpation,US,MRI and US/MRI for the surgical treatment for the cervical region in patients with carcinoma of the oropharynx.Results:Pathologic examination revealed 832 nodes,of which 33 were malignant(4.0%),an average of 41.6 lymph nodes was contained in side each;sixteen of the 100 levels contained histologically positive nodes(16.0%),of which five levels were levelⅠ,three levels were levelⅡ,four levels were levelⅢ,two levels were levelⅣand two levels were level V;Eight of the 20 sides of neck contained histologically positive nodes(40.0%).The palpation,US,MR/ and US/MR/ were compared with regard to both laterality and lymph node level(ⅠthroughⅤ).Finding per level of palpation:the true positive levels were 7,true negative levels were 81,false negative levels were 9,false positive levels were 3,the sensitivity,specificity,false-negative rate,false-positive rate and accuracy was 43.8%,96.4%,56.2%,3.6%and 88.0%;Finding per level of US:the true positive levels were 10,true negative levels were 82, false negative levels were 6,false positive levels were 2,the sensitivity, specificity,false-negative rate,false-positive rate and accuracy was 60.0%,97.6%,40.2%,2.4%and 92.0%;Finding per level of MRI:the true positive levels were 13,true negative levels were 81,false negative levels were 3,false positive levels were 3,the sensitivity,specificity, false-negative rate,false-positive rate and accuracy was 81.3%,96.4%, 18.7%,3.6%and 94.0%;Finding per level of US/MRI:the true positive levels were 13,true negative levels were 80,false negative levels were 3, false positive levels were 4,the sensitivity,specificity,false-negative rate, false-positive rate and accuracy was 81.3%,95.2%,18.7%,4.8%and 93.0%.Finding per side of palpation:the true positive levels were 5, true negative levels were 10,false negative levels were 3,false positive levels were 2,the sensitivity,specificity,false-negative rate, false-positive rate and accuracy was 62.5%,83.3%,37.5%,16.7%and 80.0%;Finding per side of US:the true positive levels were 6,true negative levels were 10,false negative levels were 2,false positive levels were 2,the sensitivity,specificity,false-negative rate,false-positive rate and accuracy was 75.0%,83.3%,25.0%,16.7%and 80.0%;Finding per side of MRI:the true positive levels were 8,true negative levels were 9, false negative levels were 0,false positive levels were 3,the sensitivity, specificity,false-negative rate,false-positive rate and accuracy was 100.0%,75.0%,0,25.0%and 85.0%;Finding per side of US/MRI:the true positive levels were 8,true negative levels were8,false negative levels were 0,false positive levels were 4,the sensitivity,specificity, false-negative rate,false-positive rate and accuracy was 100.0%,66.7%, 0,33.3%and 80.0%.The sensitivity of MRI is significantly better than that of palpation per level(p＜0.05);and the sensitivity of US/MRI is significantly better than that of palpation per level(p＜0.05).Conclusion:We prospectively estimate the accuracy of palpation,US, MRI,and US/MRI in the differentiation of benign and metastatic cervical lymph nodes in patients with carcinoma of the oropharynx,the size of nodes served as the primary criteria,and the palpation,US,MRI and US/MRI were compared for specificity,sensitivity and accuracy.The results confirm that the sensitivity of MRI is significantly better than that of palpation,and it can obtain characteristic radiologic imaging of metastatic cervical lymph nodes;there is no significant difference in sensitivity among US/MRI,US and MRI,or in the specificity of the four modalities,but it can reduce the limitation of using the three modalities alone.The frequency of occult lymph node metastasis of the four modalities is considered unacceptable to justify surgical treatment of the cervical region in patients with carcinoma of the oropharynx entirely. However,according to the prognosis and Clinicopathological characteristic of carcinoma of the oropharynx,US and MRI have partial values for surgical treatment for the cervical region in patients with carcinoma of the oropharynx.