Pattern and prognostic value of lymph node metastasis in sinonasal mucosal melanoma

Objective: To analyze the pattern of lymph node (LN) metastasis and its effect on prognosis in sinonasal mucosal melanoma (SNMM).

Methods: This retrospective study was conducted based on the Surveillance, Epidemiology, and End Results (SEER) Program data. Survival outcomes were analyzed using the Kaplan-Meier method. Factors were compared between groups using log-rank test and Fisher's exact test, and prognostic factors were screened using the Cox proportional hazards model. Propensity score matching (PSM) was conducted to examine the treatment differences after accounting for sex, age, race, T stage, N stage, and M stage.

Results: Level I (57.1%) and level II (53.6%) nodes were the most common sites of lymph node metastasis, followed by level III (17.9%) and IV (17.9%) nodes. T stage, M stage, and tumor size were associated with LN metastasis. The 5-year overall survival rates for patients without and with LN metastasis were 35.2% and 5.3%, respectively.

Conclusions: Level I and II lymph nodes may be the sentinel nodes of SNMM, Advanced T stage and increasing tumor size could promote LN metastasis. LN metastasis may promote distant metastasis and remains an important prognostic factor for patients with SNMM.