Role of contrast enhanced computed tomography in assessing cervical lymph node metastases in oral cavity squamous cell carcinoma

Abstract

Abstract Objectives: To evaluate the diagnostic accuracy of contrast enhanced CT scan to detect cervical nodal metastasis in oral cavity squamous cell carcinoma keeping final histopathology as gold standard. Methods: Cross sectional study conducted from 1st January 2015 - 31st October 2016. All patients undergoing surgery who had their CT scans done at our centre were included in the study. Diagnostic accuracy of CT scans was calculated using final histopathology as gold standard. All CT scan were reviewed by consultant radiologist. Results: Total 100 patients were reviewed, 70% were female, 55% had buccal and 32% had tongue cancer. 11 cases of T1, 20 cases of T2 , 4 cases of T3 and 21 cases of T4 stages were staged similarly by CT scan and histopathology, the kappa value of38.8%, p value <0.01. 6 cases of N1, 1 case of N2a , 9 cases of N2b, 3 cases of N2c, 1 case of N3 and 29 cases of N0 stages were staged similarly by CT scan and histopathology, with kappa value of 28.1%, p value of  <0.01. Sensitivity, specificity, positive predictive value, negative predictive value and overall diagnostic accuracy were 83%,61%,70.9%,76.3% and 73% respectively. Conclusion: CT scan is useful for preoperative staging of oral cavity squamous cell carcinoma with an overall diagnostic accuracy of 73%, currently there are no superior diagnostic modalities. However, Due to low specificity and negative predictive value elective neck dissection should still be done in a negative CT scan for cervical lymph node metastases. Keywords: Oral Cavity,