Prognostic factors in head and neck mucosal malignant melanoma

Sinonasal Mucosal Melanoma: An Update and Review of the Literature

ABSTRACT

Primary sinonasal mucosal melanoma (SNMM) is an aggressive tumor with high metastatic potential and poor outcomes. Presenting symptoms are nonspecific, and the nasal cavity is the most common site of origin followed by the maxillary and ethmoid sinuses. Histopathologically, SNMMs are pleomorphic and predominantly composed of epithelioid cell type. Identifying these tumors requires a high index of suspicion for melanoma and the use of a panel of immunohistochemical markers when typical histopathological features are missing. Not infrequently, these tumors are undifferentiated and/or amelanotic. Currently, SNMM falls into 2 different staging systems proposed by the American Joint Committee on Cancer, one for carcinoma of the nasal cavity and sinuses and the other for head and neck melanoma. Although therapeutic standards do not exist, surgical resection with adjuvant radiotherapy and/or systemic therapy may offer the best outcome. Lymphadenectomy including possible parotidectomy and neck dissection should be considered in patients with regional lymph node metastasis. However, the role of elective lymph node dissection is controversial. Genetic profiling has identified a number of recurrent gene mutations that may prove useful in providing targets for novel, emerging biological treatments. In this article, we provide an update on clinicopathological features, staging, molecular discoveries, and treatment options for SNMM.

Observed progression from melanosis with melanocyte hyperplasia to sinonasal melanoma with distant metastasis and a unique genetic rearrangement

Melanosis, clinically presenting as a benign macular hyperpigmentation, consists of increased pigmentation (melanotic or melanocytic) either in the mucosal epithelial cells or as subepithelial pigment-laden macrophages. On the other hand, primary sinonasal mucosal melanoma (SNMM) is a rare disease with poor prognosis and high rates of local recurrence and metastasis. We report follow-up on a previously presented case of a 53-year-old man with recurrent clinical melanosis that progressed from histopathological melanocytic hyperplasia to melanoma in situ over a period of 4.8 years (Yao et al. Allergy Rhinol (Providence), 2016;7(3):164-167). The patient experienced multiple recurrences and local spread despite multiple extensive surgeries. We now report that this patient ultimately developed bilateral invasive SNMM and died with metastatic melanoma. Molecular analysis of the invasive melanoma revealed ALK rearrangement, specifically an EML4-ALK fusion, which represents the first report of this particular genetic variant in mucosal melanoma.

Prognostic values of treatment modalities on head and neck mucosal melanomas in elderly patients: a population-based analysis

Background

Head and neck mucosal melanoma (HNMM) is defined as a rare malignant tumor derived from melanocytes. There is no consensus regarding the treatment protocol for HNMM in elderly patients.

Methods

The National Cancer Institute’s Surveillance, Epidemiology, and End Results database was used to identify elderly patients diagnosed with HNMM from 1975 to 2016. The chi-squared test was used to compare patient characteristics. The reverse Kaplan-Meier method was used to estimate the median follow-up time. The Kaplan-Meier method and log-rank test were used to estimate and compare the overall survival (OS) and disease-specific survival (DSS) of the groups. Cox regression analysis was used to evaluate the risk factors for OS and DSS of HNMM.

Results

Our retrospective study included 828 elderly patients with HNMM, and the 5-year OS and DSS rates were 22.4% and 27.4%, respectively. After adjusting for other variables in multivariate analysis, patients undergoing radiotherapy alone had worse OS [hazard ratio (HR) =1.449, 95% confidence interval (CI): 1.010–1.742, P=0.006] and DSS (HR =1.656, 95% CI: 1.257–2.181, P<0.001) than those undergoing surgery alone. No significant difference in OS (HR =0.892, 95% CI: 0.753–1.056, P=0.183) or DSS (HR =0.917, 95% CI: 0.764–1.101, P=0.354) was observed for patients undergoing surgery with or without radiotherapy. Our analysis of the subgroup of patients with complete clinical staging information demonstrated that the effects of surgery alone on OS (HR =0.734, 95% CI: 0.562–0.958, P=0.023) were inferior to those of surgery with radiotherapy, but no significant difference was noted compared with radiotherapy alone.

Conclusions

The survival of elderly patients with HNMM is increased with the combination of surgery and radiotherapy compared with surgery alone and radiotherapy alone. In addition, the population-based analysis demonstrated that combination therapy exhibited an obviously increased usage rate from 1975 to 2016, representing a mainstream treatment modality.

In situ melanoma of oral cavity: Diagnosis and treatment of a rare entity

Oral melanoma is an extremely aggressive and rare tumor. Commonly, oral melanomas are diagnosed as invasive tumors, which considerably reduces the chances of cure. In situ oral melanomas being exceedingly rare, which makes its clinicopathological and prognostic characteristics poorly known. Herein, we report a case of 67-year-old non-white woman with a large black patch on the maxillary alveolar mucosa. A biopsy was made and microscopical analysis revealed moderate atypical junctional melanocytic. Tumor cells were positive for S100 (Polyclonal), Melan-A (Clone A103) and Melanosome (HMB-45). The diagnosis of in situ oral melanoma was made and the patient was treated surgically with partial maxillectomy and rehabilitated with obturator prosthesis. Although extremely rare in situ melanomas should be considered in the differential diagnosis of non-invasive pigmented lesions of the oral mucosa.