Mucosal Melanoma: Epidemiology, Clinical Features, and Treatment

PURPOSE OF REVIEW

Summarize the writings published in the last years on the management and novel therapies of mucosal melanoma (MM).

RECENT FINDINGS

New research has demonstrated a difference between MM and cutaneous melanoma (CM) in their genomic and molecular landscapes, explaining the response's heterogeneity. Immunotherapy and targeted therapy have limited benefit, but novel therapies are rapidly expanding. MM is aggressive cancer occurring in gastrointestinal, respiratory, or urogenital mucosa; whose incidence is greater in the Asian population. The etiology and pathogenesis remain unclear since UV exposure is not a proven risk factor as in cutaneous melanoma. In contrast to CM, lesions on the mucosal surface are less likely to be recognized early; therefore, the disease is diagnosed in an advanced stage. Clinical manifestations, such as bleeding or pain, can help to detect this tumor, although the prognosis remains unfavorable with an overall 5-year survival rate of less than 20%. The mutational landscape of MM includes mutations of BRAF and NRAS, as well as mutations in the c-KIT/CD117 gene (in 50% of patients), thus limiting therapeutic interventions to immunotherapy. However, clinical studies show less responsiveness to immunotherapy compared to CM, therefore novel therapeutic strategies targeting new molecules are needed to improve the survival of patients with MM.

Primary mucosal melanoma of the larynx: systematic review of the literature and qualitative synthesis

PURPOSE

Primary mucosal melanoma of the larynx (PLM) is a rare entity among head and neck cancers. Due to its rarity, clear protocols of management are not available. A deeper knowledge of the clinical and biological behaviour of PLM is strongly needed.

METHODS

According to PRISMA process, we searched through electronic databases case reports, case series and review articles providing relevant clinical data. The survival analysis was performed with Kaplan-Meier survival curves, using disease free survival (DFS) and overall survival (OS) as endpoints.

RESULTS

1074 articles were initially screened, of which 37 studies describing 44 PLM cases were selected and included in the analysis. Mean age was 59.7 years with a mean follow-up time of 25.4 months. The most common symptom at presentation was hoarseness (52%), while the most involved laryngeal subsite was supraglottic region (62%). Most patients presented with an advanced stage. Tumour (T) and node (N) status at presentation did not influence OS nor DFS, whereas distant metastases (M) status resulted significantly associated with the reduction of OS and DFS time (Mantel-Cox: p < 0.0001 and p = 0.001, respectively). The laryngeal subsite and the type of surgery performed did not significantly impact on OS and DFS.

CONCLUSIONS

Treatment for PLM remains debated. Surgery with safe margins is recommended due to the high rates of local recurrence. Systemic therapy is advised for metastatic disease. However, the prognosis remains poor even after radical resection or targeted therapy.