Prognostic Implications of PRAME Expression and Clinicopathological Factors in Sinonasal Mucosal Melanoma: A Single-center Cohort Study of 30 Cases.

Background/aim: Mucosal melanoma (MM) is a rare, aggressive neoplasm in the head and neck region, primarily affecting the nasal cavity and maxillary sinus. This study investigates the correlation of PRAME IHC staining with clinicopathological factors and survival outcomes in sinonasal MM.

Patients and methods: The retrospective cohort included patients diagnosed with melanoma from January 2011 to May 2022. Histopathological reassessment confirmed MM subtype (epithelioid or spindle). IHC testing involved S100, MelanA, HMB45, SOX10, PRAME, BRAF V600E, and pan-TRK. Kaplan-Meier and Cox proportional hazards analyses explored survival probabilities and outcomes.

Results: The cohort comprised 30 patients (17 females, 13 males) with a mean age of 65 years (standard deviation 13). The 5-year survival probability was approximately 32%. Cox analysis revealed male sex and PRAME IHC staining in ≥70% of cells as associated with lower survival probability.

Conclusion: In sinonasal MM, PRAME IHC staining in ≥70% of cells is associated with significantly lower survival probability. Male sex, pN1 stage, and tumor location in the sinus are also predictive of poorer survival outcomes. These findings highlight the potential prognostic significance of PRAME expression and other clinicopathological factors in MM. Further studies are warranted to validate and expand upon these observations.