Validation of the Metastatic Formula: A Method of Cervical Lymph Nodes Assessment in Oral Cancer Patients

Background: The Metastasis Score (MS) had been introduced in 2007 as a new method for cervical nodes assessment in oral and maxillofacial cancer patients. The metastasis score (MS) was taken from the CT scan interpretation in the preoperative assessment and was found to be reliable. Objectives: To validate and evaluate the accuracy of the metastasis score (MS); a new method for cervical lymph nodes ASSESSMENT for metastasis in oral and maxillofacial cancer patients, in comparison to histopathology results. Materials and Methods: The study was conducted in Khartoum Teaching Dental Hospital, the main oral and maxillofacial referral center, during the period 2011-2013. Clinical investigation, CT scan, the metastasis scores (MS); from the CT scan interpretation, was calculated preoperatively on 25 patients who undergone neck dissection for primary head and neck malignancy. Results: Seven cases had a score of (0-3) and 18 cases had a score of (6-10). Twelve (48.0%) cases were positive (+ve) for neck metastasis and 13 (53.0%) cases were negative (-ve) for neck metastasis in the histopathology results. The histopathology results for the cases with metastasis score (MS) (0-3) showed (-ve) results in all the cases with an accuracy of 100% as there was no (+ve) results. For metastasis score (MS) the group (6-10) the histopathology results were (-ve) in 6 cases with an accuracy of 33.3% and it was (+ve) in 12 cases with an accuracy of 66.7%. The Sensitivity (true +ve results) and specificity (true -ve results) of this study are 100% and 53% respectively. Conclusion: The metastasis score (MS) predicts cervical metastasis with an accuracy of 100% for the group (0-3) and with an accuracy of 66.7% for the group (6-10) as there was an incidence of false positive results; nevertheless, this group mostly present with clinically positive neck where prophylactic neck dissection is indicated. the Metastasis