Neck dissection for oral mucosal melanoma: caution of nodular lesion

Oral mucosal melanoma (OMM) often metastasizes to cervical nodes. A great number of studies have been conducted to evaluate the efficacy of neck dissection in the treatment of OMM, but considerable controversy remains in this field.

The clinical features, treatments, and outcomes of 254 OMM patients were retrospectively analyzed from Jan. 1998 to Jul. 2012. Multivariate analysis was performed to identify the variables related to overall survival (OS).

Tumor size greater than 4 cm (p=0.01) and nodular types (p<0.0001) were independent prognostic factors for OS. Patients with nodular melanomas were more likely to have distant metastases than those with macular melanomas (p<0.0001). 164 Patients (65%) had CLN metastases. The multivariate analysis revealed that prophylactic neck dissection was an independent favorable factor for OS (p=0.0016) in patients with cN0 nodular melanomas; whereas radical neck dissection (p=0.03) in patients with positive CLN. Patients undergoing functional neck dissection were more likely to have neck recurrence (p<0.001).

Nodular type is a dangerous signal to OMM. It is advisable for patients with cN0 nodular melanomas to have prophylactic neck dissection, close observation is recommended for patients with cN0 macular melanomas, and patients with positive CLN should undergo radical neck resection.