Magnetic resonance lymphography for sentinel lymph node detection in patients with oral cavity cancer: A preliminary clinical study

Abstract

Background and Purpose: Identification of sentinel lymph nodes (LNs) is important because sentinel LN biopsy is used as an alternative procedure to elective neck dissection in patients with oral cavity cancer and clinically negative neck. The purpose of this study was to evaluate the feasibility of magnetic resonance (MR) lymphography with interstitial injection of a gadolinium-based contrast agent for identifying sentinel LNs in patients with oral cavity cancer and clinically negative neck. Methods: A total of 26 patients with resectable oral cavity cancer and clinically negative neck were recruited for this study. After peritumoral injection of 1-ml diluted gadobutrol, pretreatment MR lymphography with Differential Sub-sampling with Cartesian Ordering (DISCO) sequence was performed. The accuracy of sentinel LN identification of MR lymphography was assessed and compared with the final histopathological results after elective neck dissection. Results: MR lymphography consistently visualized the 44 sentinel LNs, defined as the first LNs to show any enhancement at the periphery portion of LNs near the injection site, in all 26 patients. After elective neck dissection, 42 assumed sentinel LNs were obtained in 24 patients, and histopathology revealed that 27 LNs from 11 patients were metastatic. In all but one patient with pathologically positive neck, assumed sentinel LNs revealed metastatic involvement. Conclusions: Pretreatment MR lymphography is a safe and feasible imaging technique that can help clinicians identify sentinel LNs with a high risk of occult metastases in patients with oral cavity cancer and clinically negative neck, enabling focused preoperative biopsy in these high-risk patients