Sinonasal tract and nasopharyngeal melanomas: a clinicopathologic study of 115 cases with a proposed staging system

Immunotherapy in the Management of Sinonasal Mucosal Melanoma: A Systematic Review

OBJECTIVE

The aim of this work is to comprehensively review and synthesize the literature related to sinonasal mucosal melanoma (SNMM) treatment with immunotherapy, including potentially targetable genetic mutations, survival outcomes, and adverse events.

DATA SOURCES

Embase, Cochrane, Scopus, and Web of Science.

REVIEW METHODS

The study protocol was designed according to Preferred Reporting Items for Systematic Reviews and Meta-analysis statement. Databases were searched from inception through May 23, 2023.

RESULTS

A total of 42 studies met inclusion criteria. Twenty-four of the included studies reported genetic mutations for a combined 787 patients with SNMM. 8.1% (95% confidence interval, CI: 7.6-8.6), 18.9% (95% CI: 18.1-19.8), and 8.5% (95% CI: 8.1-9.0) of reported patients were positive for BRAF, NRAS, and KIT mutations, respectively. The presence of brisk tumor-infiltrating lymphocytes was associated with improved recurrence-free survival and overall survival (OS). Six studies reported a combined 5-year OS after adjuvant immunotherapy treatment of 42.6% (95% CI: 39.4-45.8). Thirteen studies encompassing 117 patients reported adjuvant or salvage immune checkpoint inhibitor (ICI) immunotherapy response rates: 40.2% (95% CI: 36.8-43.6) had a positive response (tumor volume reduction or resolution). Eleven studies reported direct comparisons between SNMM patients treated with or without immunotherapy; the majority (7/11) reported survival benefit for their entire cohort or select subgroups of SNMM patients. With the transition to modern ICIs, there is a stronger trend toward survival improvement with adjuvant ICI. Tumors with Ki67 <40% may respond better to ICI's.

CONCLUSION

ICI therapy can be an effective in select SNMM patients, especially those with advanced/metastatic disease.

Unveiling Oral Malignant Melanoma: Clinicopathological Details of a Case

Oral malignant melanoma is a rare tumor of the oral cavity. It is more common among Negros and Japanese people. Initial symptoms are frequently overlooked, resulting in a delayed diagnosis and poor prognosis with a 5-year survival rate. Unlike melanomas in other sites, it is uncommon and thus lacks a well-defined classification system and treatment regimen. The survival rate is mainly correlated with early diagnosis and treatment. A 54-year-old male reported to our department with a de novo fast-growing exophytic proliferative pigmented lesion for six months. After proper radiographic analysis, an incisional biopsy was done which revealed the presence of nests and fascicles of pleomorphic spindle cells with hyperchromatic nuclei and abundant brown pigments rendering it a provisional diagnosis of oral malignant melanoma which was later confirmed by immunohistochemistry (IHC). PET-CT scan revealed widespread metastasis. This article stresses the importance of identification of initial symptoms which are frequently overlooked, resulting in a delayed diagnosis and poor prognosis.

[About a case of primary laryngeal mucosal melanoma in a patient with medical history of oropharyngeal squamous carcinoma]

INTRODUCTION

Primary laryngeal mucosal melanoma is a rare tumour with a poor prognosis. Its often difficult diagnosis should rule out laryngeal metastatic localization of cutaneous melanoma.

CASE PRESENTATION

We report a case of primary laryngeal mucosal melanoma diagnosed in a 65-year-old man, treated 6 years previously with radio-chemotherapy and surgery for squamous cell carcinoma of the right lateral oropharyngeal region. The definitive diagnosis of primary laryngeal mucosal melanoma was made on the resection specimen, whereas the initial biopsy of the epilaryngeal mass discovered during the patient's surveillance had concluded that it was a laryngeal recurrence of the known squamous cell carcinoma.

DISCUSSION

Through this case, we propose to remind the main characteristics and the diagnostic pitfalls of these tumours.

Primary Nasopharyngeal Melanoma without invasive and Metastasis: A Rare Case Reports and Literature Reviews

Objective: Nasopharyngeal melanoma is a rare mucosal malignant melanoma with high recurrence rate, metastasis rate and vascular invasion rate. In this paper, we report a case of primary nasopharyngeal mucosal melanoma. Methods: A case of primary nasopharyngeal mucosal melanoma was reported, and its clinical symptoms, pathological characteristics, treatment and follow-up were described in detail. Results: This report describes a 59-year-old male patient with persistent nasal congestion and suspected malignant nasopharyngeal neoplasm. Patients receive surgical resection and adjuvant radiotherapy after complete resection. Imaging studies showed no tissue invasion or lymph node metastases. The results of immunohistochemistry were Melan-A(+), HMB45(+), and S100(+). The final diagnosis was malignant nasopharyngeal melanoma. After 2 years of follow-up, the prognosis was good, and there was no metastasis or recurrence. Discussion: Nasopharyngeal melanoma is a rare malignancy with a poor prognosis, and surgical resection is the mainstay of treatment. Postoperative adjuvant therapy can improve the rate of local control of lesions. Early diagnosis and thorough examination are extremely important for the patient's prognosis.

The Small Round Blue Cell Tumors of Sinonasal Tract: Pathologists Grey Zone

Background

One of the most challenging diagnostic categories in the sinonasal tract includes small-blue-round-cell tumors. These are malignant tumors which show many overlapping histomorphology and immunohistochemistry (IHC) findings. Limited, small biopsy of these not completely excisable tumors adds to the diagnostic confusion.

Materials and Methods

A cross-sectional study was done for 2 years (January 2018-December 2020) in a tertiary care institute, which included 70 cases of tumors of which 49 cases were malignant. All paraffin-embedded blocks were subjected to hematoxylin and eosin stain and IHC followed by molecular study wherever needed.

Results

Of the total cases, small-blue-round-cell tumor constituted the major category comprising 20 rare and interesting cases which included sinonasal undifferentiated carcinoma (4 cases), malignant lymphoma (2 cases of diffuse large B-cell lymphoma and 2 cases of extranodal natural killer/T-cell lymphoma), rhabdomyosarcoma (2 cases), olfactory neuroblastoma (2 cases), malignant melanoma (2 cases), plasmacytoma (2 cases), atypical Ewing's sarcoma (EWS) (1 case), EWS (1 case), nuclear protein in testis (NUT) carcinoma (1 case), and small-cell neuroendocrine carcinoma (1 case).

Conclusion

Tumors of the sinonasal tract are very diverse, more so in small-round-cell tumor which present with a undifferentiated morphology. Thus, accurate diagnosis needs clinicoradiological parameters and special ancillary techniques such as IHC and molecular study in addition to histopathology for early diagnosis and therapy to prevent significant morbidity and mortality caused in these tumors.

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.

The Role of Positron Emission Tomography for the Management of Sinonasal Malignancies: A Systematic Review

BACKGROUND

Positron emission tomography (PET) scan is a valuable imaging modality widely used in the management of cancers. Its usage is well defined for most head and neck malignancies. However, there is a lack of consensus regarding the utility of PET scan for sinonasal malignancies. This is highlighted by the latest international consensus statement on endoscopic skull base surgery.

OBJECTIVE

This systematic review aims to clarify the role of PET scan in the management of sinonasal malignancies.

METHODS

We conducted a comprehensive literature search using PubMed, MEDLINE, EMBASE, Web of Science, CINAHL, and Cochrane databases for research studies of interest. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) updated statement was used to guide the review.

RESULTS

In total, 1807 articles were assessed for eligibility. Thirty-nine original papers, published between 2004 and 2021, met inclusion criteria. Seven articles focused on the role of PET scan for inverted papilloma, 23 for sinonasal carcinoma, 4 for melanoma, and 3 for lymphoma, and finally, 3 articles focused on the use of specific PET scan tracers for sinonasal malignancies. Qualitative summaries for each potential role of PET scans were provided. In general, included studies were retrospective in nature with low level of evidence.

CONCLUSIONS

In general, and across all types of sinonasal malignancies, PET scan yielded positive results regarding detection and initial staging. It was also considered as the modality of choice for detection of distant metastases, except in the case of sinonasal lymphoma. PET scan's main limit resides in its inability to detect lesions in or close to the metabolic activity of the brain.

PET/CT Imaging in Treatment Planning and Surveillance of Sinonasal Neoplasms

Sinonasal cancers are uncommon malignancies with a generally unfavorable prognosis, often presenting at an advanced stage. Their high rate of recurrence supports close imaging surveillance and the utilization of functional imaging techniques. Whole-body 18F-FDG PET/CT has very high sensitivity for the diagnosis of sinonasal malignancies and can also be used as a "metabolic biopsy" in the characterization of some of the more common subgroups of these tumors, though due to overlap in uptake, histological confirmation is still needed. For certain tumor types, radiotracers, such as 11C-choline, and radiolabeled somatostatin analogs, including 68Ga-DOTATATE/DOTATOC, have proven useful in treatment planning and surveillance. Although serial scans for posttreatment surveillance allow the detection of subclinical lesions, the optimal schedule and efficacy in terms of survival are yet to be determined. Pitfalls of 18F-FDG, such as post-surgical and post-radiotherapy crusting and inflammation, may cause false-positive hypermetabolism in the absence of relapse.

Nasal Malignant Melanoma With an Inverted Papilloma in the Contralateral Nasal Cavity: A Case Report

Background: We describe a patient with sinonasal mucosal melanoma (SNMM) and an inverted papilloma, which existed independently in both nasal cavities. Case presentation: We describe an unusual case of a 74-year-old male patient with SNMM and an inverted papilloma. He presented with symptoms of coughing up blood and pain in the left forehead. The patient underwent surgical resection of the lesion, and the SNMM and inverted papilloma were confirmed by histopathology. The patient refused further treatment after surgery, but was re-admitted 7 months later with local recurrence of the left tumor and systemic metastases. Conclusions: Nasal malignant melanoma with an inverted papilloma in the contralateral nasal cavity is rare and can easily be misdiagnosed as the same tumor by imaging. Simultaneous histopathology of bilateral nasal masses is very necessary. The recommended treatment is surgery for the inverted papilloma. An SNMM is a devastating tumor with poor outcomes.

Translocations and Gene Fusions in Sinonasal Malignancies

PURPOSE OF REVIEW

During the past few years there has been an expansion in our understanding of gene fusions and translocations involved in cancer of the sinonasal tract. Here we review the downstream biologic effects, clinical characteristics, and pathologic features of these tumors. The molecular consequences and neo-antigens resulting from these chromosomal aberrations are considered and targets for current and future clinical trials discussed.

RECENT FINDINGS

Several new, clinically relevant, chromosomal aberrations have been discovered and evaluated to varying degrees in sinonasal tumors including DEK::AFF2, BRD4::NUT, ADCK4::NUMBL, and ETV6::NTRK3. Sinonasal malignancies demonstrate a diverse genetic landscape and varying clinical courses. Recent studies illustrate that gene fusions and translocations may play a role in carcinogenesis in certain sinonasal tumor subtypes and may be used to develop new biomarker-driven and patient-centered treatments.

Top Ten Differentials to Mull Over for Head and Neck Myoepithelial Neoplasms

BACKGROUND

Myoepithelial neoplasms of the salivary gland are benign or malignant neoplasms composed exclusively of neoplastic myoepithelial cells. These tumors, including the benign myoepithelioma and the malignant counterpart myoepithelial carcinoma, exhibit a wide range of cytomorphologic features and architectural patterns.

METHODS

Review.

RESULTS

Myoepithelial cells can be epithelial, plasmacytoid, clear cell, spindle cell, and/or oncocytic cell, arranging as trabeculae, solid sheets, nests, cords, and/or single cells. A stromal component is commonly but not universally present, Therefore, their differential diagnoses are quite broad, including salivary gland neoplasms especially those with a myoepithelial component, plasmacytoma, melanoma, and various mesenchymal tumors.

CONCLUSION

In this review, we summarize the characteristic histologic features, useful immunohistochemical panel, and common molecular alterations of myoepithelial tumors and their top differential diagnoses. A logical stepwise algorithmic approach and an immunohistochemical panel to include multiple myoepithelial markers are essential to establish the correct diagnosis.

Primary mucosal melanomas of the head and neck are characterised by overexpression of the DNA mutating enzyme APOBEC3B

AIMS

Primary head/neck mucosal melanomas (MMs) are rare and exhibit aggressive biologic behaviour and elevated mutational loads. The molecular mechanisms responsible for high genomic instability observed in head/neck MMs remain elusive. The DNA cytosine deaminase APOBEC3B (A3B) constitutes a major endogenous source of mutation in human cancer. A3B-related mutations are identified through C-to-T/-G base substitutions in 5'-TCA/T motifs. Herein, we present immunohistochemical and genomic data supportive of a role for A3B in head/neck MMs.

METHODS AND RESULTS

A3B protein levels were assessed in oral (n = 13) and sinonasal (n = 13) melanomas, and oral melanocytic nevi (n = 13) by immunohistochemistry using a custom rabbit α-A3B mAb (5210-87-13). Heterogeneous, selective-to-diffuse, nuclear only, A3B immunopositivity was observed in 12 of 13 (92.3%) oral melanomas (H-score range = 9-72, median = 40) and 8 of 13 (62%) sinonasal melanomas (H-score range = 1-110, median = 24). Two cases negative for A3B showed prominent cytoplasmic staining consistent with A3G. A3B protein levels were significantly higher in oral and sinonasal MMs than intraoral melanocytic nevi (P < 0.0001 and P = 0.0022, respectively), which were A3B-negative (H-score range = 1-8, median = 4). A3B levels, however, did not differ significantly between oral and sinonasal tumours (P > 0.99). NGS performed in 10 sinonasal MMs revealed missense NRAS mutations in 50% of the studied cases and one each KIT and HRAS mutations. Publicly available whole-genome sequencing (WGS) data disclosed that the number of C-to-T mutations and APOBEC3 enrichment score were markedly elevated in head/neck MMs (n = 2).

CONCLUSION

The above data strongly indicate a possible role for the mutagenic enzyme A3B in head/neck melanomagenesis, but not benign melanocytic neoplasms.

Top 10 Basaloid Neoplasms of the Sinonasal Tract

BACKGROUND

Basaloid neoplasms of the sinonasal tract represent a significant group of tumors with histological overlap but often with different etiologies (i.e., viral, genetics), clinical management, and prognostic significance.

METHODS

Review.

RESULTS

"Basaloid" generally refers to cells with coarse chromatin in round nuclei and sparse cytoplasm, resembling cells of epithelial basal layers or imparting an "immature" appearance. Tumors with this characteristic in the sinonasal tract are represented by a spectrum of benign to high-grade malignant neoplasms, such as adenoid cystic carcinoma, NUT carcinoma, sinonasal undifferentiated carcinoma, SWI/SNF complex-deficient carcinomas, and adamantinoma-like Ewing sarcoma.

CONCLUSION

In some instances, histology alone may be sufficient for diagnosis. However, limited biopsy material or fine-needle aspiration specimens may be particularly challenging. Therefore, often other diagnostic procedures, including a combination of histology, immunohistochemistry (IHC), DNA and RNA testing, and molecular genetics are necessary to establish an accurate diagnosis.

Top 10 Significant Spindled Head and Neck Lesions to Scrutinze

BACKGROUND

Spindled lesions are a challenging area in head and neck pathology. This is particularly true in the sinonasal tract, where several uncommon entities with both unique and overlapping morphologic, immunophenotypic, and/or molecular features can occur.

METHODS

Review.

RESULTS

The clinicopathologic characteristics of biphenotypic sinonasal sarcoma and nine important differential diagnostic considerations with one or more overlapping feature are summarized to establish a practical framework for approaching spindled lesions of the sinonasal tract.

CONCLUSION

Morphologic evaluation is central to the work up of sinonasal spindle cell lesions-in particular, cellular morphology, tumor architecture and growth pattern, and the presence of admixed epithelial elements - however, focused immunohistochemical analysis of neural, myogenic, rhabdomyoblastic, epithelial, and/or melanocytic marker expression and/or ancillary tests for tumor-specific molecular alterations may be necessary for definitive diagnosis.

Current Trends in Mucosal Melanomas: An Overview

Primary mucosal melanomas (MMs) are uncommon tumors originating from melanocytes located in the mucous membranes at various anatomic sites within the body. MM significantly differs from cutaneous melanoma (CM) regarding epidemiology, genetic profile, clinical presentation, and response to therapies. Despite these differences, that have important implications for both disease diagnosis and prognosis, MMs are usually treated in the same way as CM but exhibit a lower response rate to immunotherapy leading to a poorer survival rate. Furthermore, a high inter-patient variability can be observed in relation to therapeutic response. Recently, novel "omics" techniques have evidenced that MM lesions have different genomic, molecular, and metabolic landscapes as compared with CM lesions, thus explaining the heterogeneity of the response. Such specific molecular aspects might be useful to identify new biomarkers aimed at improving the diagnosis and selection of MM patients who could benefit from immunotherapy or targeted therapy. In this review, we have focused on relevant molecular and clinical advancements for the different MM subtypes in order to describe the updated knowledge relating to main diagnostic, clinical, and therapeutic implications as well as to provide hints on likely future directions.

Oncoviruses and melanomas: A retrospective study and literature review

The role of human oncoviruses in melanoma has been poorly investigated. The aim of this study was to investigate the association between oncoviruses and melanomas searching for human papillomavirus (HPV), Epstein Barr virus (EBV), and human herpesvirus 8DNA in melanoma specimens. Formalin-fixed and paraffin-embedded tissue specimens of cutaneous, mucosal, and ocular melanomas (OM) were selected from the Pathology Departments of the Galliera Hospital (Genoa) and the University Hospitals of Turin and Cagliari. Cutaneous and mucosal nevi have been collected as controls. The oncoviruses search has been performed with different polymerase chain reaction reagent kits. Fifty-four melanomas (25 mucosal, 12 ocular, and 17 cutaneous) and 26 nevi (15 cutaneous and 11 mucosal) specimens were selected. The detection rate for one of the investigated oncoviruses was 17% in mucosal, 20% in ocular, and 0% in cutaneous melanomas (CMs). Despite the differences between groups seeming remarkable, there was no statistical significance (p > 0.5). Our data do not support a primary role of oncoviruses in melanoma carcinogenesis; however, the finding of HPV and EBV DNA in a considerable fraction of mucosal and OMs suggests that these viruses may act as cofactors in the development of extra-CMs.

Primary Malignant Melanoma of the Oral Cavity: A Retrospective Study From a Tertiary Care Centre of North India

BACKGROUND

Mucosal melanoma is a rare but aggressive tumor associated with a poor prognosis arising from pigmented cells called melanocytes. They are usually asymptomatic and present in an advanced stage. It has an aggressive clinical outcome and is proven to be of poor prognosis.

MATERIALS AND METHODS

This is a retrospective review of the computer database and clinical records at the All India Institute of Medical Sciences, Rishikesh, India. The data between 2018-2022 were reviewed for all small biopsy or excision specimen-proven cases of oral mucosal melanoma.

RESULTS

The most common site of involvement in the head and neck region is the nasal cavity and paranasal sinuses. In this retrospective study from our institute, all three cases presented involved oral cavities. The median age of presentation was 51 years. Some literature specifies male preponderance. Our patients presented clinically with a black nodule in the oral cavity, which was increasing in size and associated with bleeding. A biopsy performed confirmed the diagnosis of melanoma based on the morphology and immunohistochemical profile of the tumor cells.

CONCLUSION

Surgical resection is the mainstay treatment, followed by radiation postoperatively to reduce local and regional recurrence. Mucosal melanoma has a poor prognosis, and the majority of patients develop incurable metastatic disease.

Alterations in key signaling pathways in sinonasal tract melanoma. A molecular genetics and immunohistochemical study of 90 cases and comprehensive review of the literature

Sinonasal mucosal melanoma is a rare tumor arising within the nasal cavity, paranasal sinuses, or nasopharynx (sinonasal tract). This study evaluated 90 cases diagnosed in 29 males and 61 females with median age 68 years. Most tumors involved the nasal cavity and had an epithelioid morphology. Spectrum of research techniques used in this analysis includes targeted-DNA and -RNA next-generation sequencing, Sanger sequencing, fluorescence in situ hybridization and immunohistochemistry. Sinonasal melanomas were commonly driven by RAS (38/90, 42%), especially NRAS (n = 36) mutations and rarely (4/90, 4%) displayed BRAF pathogenic variants. BRAF/RAS mutants were more frequent among paranasal sinuses (10/14, 71%) than nasal (26/64, 41%) tumors. BRAF/RAS-wild type tumors occasionally harbored alterations of the key components and regulators of Ras-MAPK signaling pathway: NF1 mutations (1/17, 6%) or NF1 locus deletions (1/25, 4%), SPRED1 (3/25, 12%), PIK3CA (3/50, 6%), PTEN (4/50, 8%) and mTOR (1/50, 2%) mutations. These mutations often occurred in a mutually exclusive manner. In several tumors some of which were NRAS mutants, TP53 was deleted (6/48, 13%) and/or mutated (5/90, 6%). Variable nuclear accumulation of TP53, mirrored by elevated nuclear MDM2 expression was seen in >50% of cases. Furthermore, sinonasal melanomas (n = 7) including RAS/BRAF-wild type tumors (n = 5) harbored alterations of the key components and regulators of canonical WNT-pathway: APC (4/90, 4%), CTNNB1 (3/90, 3%) and AMER1 (1/90, 1%). Both, TERT promoter mutations (5/53, 9%) and fusions (2/40, 5%) were identified. The latter occurred in BRAF/RAS-wild type tumors. No oncogenic fusion gene transcripts previously reported in cutaneous melanomas were detected. Eight tumors including 7 BRAF/RAS-wild type cases expressed ADCK4::NUMBL cis-fusion transcripts. In summary, this study documented mutational activation of NRAS and other key components and regulators of Ras-MAPK signaling pathway such as SPRED1 in a majority of sinonasal melanomas.

Amelanotic Melanoma: A Great Masquerader

Malignant melanoma is an aggressive, notorious tumor showing great variability in morphological and immunohistochemical expression, thus commonly leading to an erroneous diagnosis. Within the melanoma group, amelanotic melanoma, with its wide clinical presentations, lack of pigmentation, and varied histological appearances, has taken on a new persona as a master masquerader. Use of immunohistochemistry in the diagnosis of malignant tumors, including melanoma, is primordial and indispensable. However, the problem gets compounded in scenario of aberrant antigenic expression. The present case posed multiple diagnostic challenges in form of atypical clinical presentation, variant morphology, as well as aberrant antigenic expression. Here, we present the case of a 72-year-old male who, upon his initial presentation, was thought to be sarcomatoid anaplastic plasmacytoma, but 5 months later another biopsy from a different site revealed the actual diagnosis of amelanotic melanoma.

Sinonasal mucosal melanomas: defining profiles for better survival outcomes

BACKGROUND

Sinonasal mucosal melanoma is an aggressive malignancy with a 5-year survival rate ranging from 20% to 39%. Despite the evolving surgical and radiotherapy techniques, and introduction of immune-checkpoint inhibitor therapy, overall survival rates remain poor.

METHODOLOGY

A retrospective cohort study was conducted at the Hospital Clinic de Barcelona and the Hospital de la Santa Creu i Sant Pau between 1984 and 2020; primary outcome measures were 3 and 5-year melanoma-specific survival (MSS). Kaplan-Meier survival analysis and Cox proportional hazards model were performed to identify predictors of survival.

RESULTS

Fifty patients were included, the mean age was 70.4, MSS at 3 and 5 years was 51.2%, and 29.5%, respectively. The median follow-up was 39.6 months during which 46% presented locoregional recurrence and 36%, metastasis. The univariate and multivariate analyses found as survival predictors the N category, the treatment received, the surgical margins and the mitotic index.

CONCLUSIONS

We found an overall 5-year MSS of 29.5%. Those patients with intention-to-cure (stages III and IVa) treated by surgery that were N0 at diagnosis, with < 10 mitoses per HPF showed a 5-year MSS rate of 74.1%. More studies will be needed to adequately define the patients' profiles that will benefit from a better survival outcome.

Primary Oral Mucosal Melanoma: A Case Series

Mucosal melanoma is an exceedingly rare and aggressive neoplasm with high mortality rate. In contrast to the cutaneous melanomas, the risk factors and pathogenesis are poorly understood. It is predominantly localized in the region of the hard palate and maxillary alveolus. Surgery is the mainstay of treatment, but it may turn out to be challenging depending on the anatomic location, extent and size of the tumor and presence of metastasis. Presented here is a series of two cases of maxillary mucosal melanoma with varied presentation.

Sinonasal Mucosal Melanoma: Role of Tumor Proliferative Indices and Pathological Factors in Survival

OBJECTIVE

The objective of this study is to determine the association of proliferation indices and pathologic biomarkers on overall and recurrence/metastasis-free survival (OS and RMFS) in patients with sinonasal mucosal melanoma (SNMM) and to assess the genetic mutational landscape of SNMM.

METHODS

This is a retrospective cohort study of 45 SNMM patients without neoadjuvant therapy who underwent surgical therapy with curative intent and had tumor tissue available for histopathologic review, molecular analysis, and genetic mutational assessment. The OS and RMFS were assessed for associations with numerous tumor and patient-related factors.

RESULTS

Among proliferative indices, higher Ki67 and mitotic rates were associated with worsened OS and RMFS (Ki67: p = 0.0007 and p < 0.0001; mitotic rate: p = 0.005 and p = 0.0009, respectively). The presence of brisk tumor-infiltrating lymphocytes (TILs) was associated with improved RMFS (p = 0.007) and the presence of lymphovascular invasion was associated with worsened OS and RMFS (p = 0.02 and p = 0.04, respectively). Patients with amelanotic tumors were more likely to have higher T-stage (p = 0.046), less likely to have brisk TILs (p = 0.02) and had worsened RMFS (p = 0.03). Patients on immunotherapy with tumor Ki67 < 40% had better 3-year OS compared to those with higher Ki67 index (p = 0.004). Actionable genetic mutations such as BRAF V600E are rare and present in only 1 of 20 patients tested.

CONCLUSION

In SNMM patients, pathologic and proliferation markers such as Ki67, mitotic rate and brisk TILs are associated with survival and may be considered in future staging systems. Clinical response to immunotherapy appears to correlate with the Ki67 index. Given the distinct genetic profile of SNMM, targeted therapies against the MAPK kinase pathway have limited utility.

LEVEL OF EVIDENCE

3 Laryngoscope, 2022.

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.

Base of tongue metastasis of cutaneous malignant melanoma with rhabdoid and neuroendocrine features: Report of a rare case and review of the literature

Metastatic malignant melanoma (MM) represents a highly aggressive cancer associated with overall poor prognosis. Various anatomic sites can be affected, including the oral cavity and the oropharynx. It may mimic other entities by assuming a variety of clinical appearances and exhibiting a plethora of microscopic variations. Herein, we present a case of a 63-year-old male with a MM metastasizing to the base of tongue, which developed 5 years after the original diagnosis and treatment of cutaneous MM of the chest and heralded its relapse; subsequently, neurological symptoms developed as a result of metastasis to the brain. Diagnostic challenges were encountered, as the tongue lesion clinically masqueraded as a pedunculated reactive lesion and microscopically displayed unusual rhabdoid and neuroendocrine features. Tumor cells expressed S-100, HMB-45, Melan-A, and SOX-10, while most cells with rhabdoid morphology were also positive for myogenin and Myo-D1. Chromogranin and synaptophysin positivity was further noticed in a subset of cells, suggestive of focal neuroendocrine differentiation. Molecular investigation revealed mutations for the BRAF V600E gene. Divergent differentiation of tumor cells may cause diagnostic pitfalls necessitating thorough immunohistochemical analysis. The presence of rhabdoid features and neuroendocrine differentiation are very uncommon, while their co-existence is extremely rare. Better characterization of such microscopic variations in MMs with evaluation of their potential biologic significance is warranted.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: The Neck and Lymph Nodes, Metastasis, and Melanocytic Tumors

The changes made in the fifth edition of the WHO Classification of Head and Neck Tumors demonstrate the recent diagnostic, histopathological, and molecular advances in the field, and this updated information will hopefully lead to improved and standardized tumor subtyping. This review summarizes the changes related tumors and tumor-like lesions of the neck and lymph nodes (Chapter 11), metastasis to the head and neck region (Chapter 15), and melanocytic tumors (Chapter 10).

Sinonasal Mucosal Melanoma: A Population-Based Comparison of the EUROCARE and SEER Registries

Introduction  Sinonasal melanomas are rare tumors with no comparative survival studies between Europe and the US.

Objective  To provide a population-based survival analysis between the two continents.

Methods  The European Cancer Registry (EUROCARE) and the United States Surveillance, Epidemiology, and End Results (SEER) databases were queried to identify patients diagnosed with sinonasal melanoma between 2000 and 2007. Relative survival (RS) data were grouped by age, gender, geographic region, extent of disease, and treatment modality.

Results  A total of 1,294 cases were identified between 2000 and 2007 (935 from EUROCARE-5 and 359 from SEER). Females were most commonly identified in Europe (56.4%) and in the US (54.9%). Patients over the age of 65 years comprised the greatest proportion of patients in Europe (70%) and in the US (71%). By region, Southern Europe had the highest 5-year RS (31.6%, 95% confidence interval [CI] = [21.3–42.5%]), and Eastern Europe the lowest (16.5%, [7.5–28.5%]). The aggregate European 5-year RS was 25.4% [21.8–29.1%] and the U.S. was (29.7%, [23.6–36%]).

Conclusions  Although increasing in incidence, sinonasal melanomas remain rare. Women were more commonly affected. The most common age group was those older than 65 years, although age did not confer a prognostic value. The most common subsite was the nasal cavity followed by the maxillary sinus. Five-year RS was similar between continents with an inverse relationship between extent of disease and survival. The treatment of choice throughout Europe and the US remains primarily surgical.

New Therapeutic Approaches for Conjunctival Melanoma-What We Know So Far and Where Therapy Is Potentially Heading: Focus on Lymphatic Vessels and Dendritic Cells

Conjunctival melanoma (CM) accounts for 5% of all ocular melanomas and arises from malignantly transformed melanocytes in the conjunctival epithelium. Current therapies using surgical excision in combination with chemo- or cryotherapy still have high rates for recurrences and metastatic disease. Lately, novel signal transduction-targeted and immune checkpoint inhibitors like cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitors, programmed cell death protein-1 (PD-1) receptor inhibitors, BRAF- or MEK-inhibitors for systemic treatment of melanoma have improved the outcome even for unresectable cutaneous melanoma, improving patient survival dramatically. The use of these therapies is now also recommended for CM; however, the immunological background of CM is barely known, underlining the need for research to better understand the immunological basics when treating CM patients with immunomodulatory therapies. Immune checkpoint inhibitors activate tumor defense by interrupting inhibitory interactions between tumor cells and T lymphocytes at the so-called checkpoints. The tumor cells exploit these inhibitory targets on T-cells that are usually used by dendritic cells (DCs). DCs are antigen-presenting cells at the forefront of immune response induction. They contribute to immune tolerance and immune defense but in the case of tumor development, immune tolerance is often prevalent. Enhancing the immune response via DCs, interfering with the lymphatic pathways during immune cell migration and tumor development and specifically targeting tumor cells is a major therapeutic opportunity for many tumor entities including CM. This review summarizes the current knowledge on the function of lymphatic vessels in tumor growth and immune cell transport and continues to compare DC subsets in CM with related melanomas, such as cutaneous melanoma and mucosal melanoma.

Comparative Review of Malignant Melanoma and Histologically Well-Differentiated Melanocytic Neoplasm in the Oral Cavity of Dogs

Oral malignant melanoma (OMM) is the most common neoplasm of the canine oral cavity. It is characterized by its aggressive local disease as well as its high rate of lymphatic invasion and distant metastasis. OMM carries a poor prognosis, with most patients succumbing to the disease due to progression of the neoplasm. Histopathologically, OMM is characterized by significant nuclear atypia, a mitotic index of greater than 4/10 hpf, and evidence of vascular invasion or metastasis. Clinically, these lesions can become locally invasive, causing lysis of bones and severe inflammation of the surrounding soft tissue. With time, these lesions can spread to the regional lymph node and to the lungs and other organs. Prognosis can vary depending on the size of the primary tumor, regional node involvement, and distant metastatic disease; however, multiple studies report a relatively short median survival time ranging from less than 4 months to 8 months. Histologically well- differentiated melanocytic neoplasms (HWDMN) are a variant of OMM and sometimes referred to as canine oral melanocytic neoplasms of low malignant potential. Unlike OMM, patients with HWDMN have longer survival times. Histopathologically, HWDMNs have well-differentiated melanocytes with a low mitotic index of 3 or less per 10 hpf and minimal nuclear atypia. HWDMNs have better prognosis with a mean survival time of up to 34 months. This article is a comparative review of OMM and its less aggressive counterpart.

Nasal and paranasal sinus mucosal melanoma: Long-term survival outcomes and prognostic factors

OBJECTIVE

To determine prognostic factors and survival patterns for different treatment modalities for nasal cavity (NC) and paranasal sinus (PS) mucosal melanoma (MM).

METHODS

Patients from 1973 to 2013 were analyzed using the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier method and multivariable cox proportional hazard modeling were used for survival analyses.

RESULTS

Of 928 cases of mucosal melanoma (NC = 632, PS = 302), increasing age (Hazard Ratio [HR]:1.05/year, p < 0.001), T4 tumors (HR: 1.81, p = 0.02), N1 status (HR: 6.61, p < 0.001), and PS disease (HR: 1.50, p < 0.001) were associated with worse survival. Median survival length was lower for PS versus NC (16 versus 26 months, p < 0.001). Surgery and surgery + radiation therapy (RT) improved survival over non-treatment or RT alone (p < 0.001). Adding RT to surgery did not yield a survival difference compared with surgery alone (p = 0.43). Five-year survival rates for surgery and surgery + RT were similar, at 27.7% and 25.1% (p = 0.43).

CONCLUSION

Surgery increased survival significantly over RT alone. RT following surgical resection did not improve survival.

A Case of Blue Nevus of the Nasal Septum

Blue nevus (BN) is a blue- or black-colored benign melanocytic proliferation that commonly occurs on the dorsal surface of the hands and feet or in the head and neck region. However, BN arising from the sinonasal mucosa is extremely rare. BN is usually asymptomatic and small in size. Based on the pigmentation of BN, sinonasal malignant melanoma should be considered in the differential diagnosis of BNs in this region. We herein report a case of BN of the nasal septum. Histopathologic examination revealed the presence of heavily pigmented, spindle-shaped melanocytic cells within the stromal tissue. On immunohistochemical analysis, BN cells were positive for S-100 and HMB-45. Due to the few reported cases of sinonasal BN and challenging location, complete resection, biopsy, and adequate follow-up are recommended.

Primary sinonasal myxofibrosarcoma: a clinicopathological study of five cases and review of the literature

Myxofibrosarcoma is a malignant pleomorphic fibroblastic sarcoma with variably myxoid stroma, and is characterised by a distinctive curvilinear vascular pattern. In the head and neck area, myxofibrosarcoma is extremely rare, with only a handful of case reports in the literature to date. We report the first case series of primary sinonasal myxofibrosarcoma across two institutions. Among the five cases (2 female, 3 males, aged 52-82 years old), four arose from the maxillary sinus and one from the sphenoid sinus. Four patients received surgical resection and three with adjuvant radiotherapy. The tumours ranged from 2.9 to 5.6 cm in greatest dimensions. All tumours demonstrated extensive myxoid stroma (>50% myxoid component) with a characteristic curvilinear, elongated, thin-walled vasculature with perivascular condensation of tumour cells. All but one were classified as intermediate to high grade myxofibrosarcoma. Among the four patients with follow-up information, three reported no local recurrence or distal metastasis, and one had local recurrence. Myxofibrosarcoma should be included in the differential diagnosis of sinonasal tumours with a pleomorphic spindle cell morphology and a 'null' immunophenotype.

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.

Fortuitous discovery of melanomas in the ENT Department - a histopathological and immunohistochemical study

The melanoma, having its origin in the melanocyte cells, is one of the most aggressive forms of skin cancer in the world with one of the highest rates of brain metastasis. The incidence of cutaneous melanoma in the Mediterranean countries varies from three to five cases/100 000 people/year. Its prognosis is based on an early diagnosis. Sinonasal mucosal melanoma (SNMM) is an extremely rare tumor, accounting for 0.3–2% of all melanomas. The non-specific symptomatology is often delaying the presentation of the patient at the hospital and therefore the diagnosis. The SNMM is a highly aggressive tumor, and the presence of metastasis at the diagnosis usually implies a poor prognosis. The management of the melanomas requires a precise pre-therapeutic assessment and a multidisciplinary approach for the diagnosis, with surgical treatment or radiotherapy required in order to ensure a better a quality of life. In this paper, we retrospectively analyzed two cases of mucosal melanoma and one case of cutaneous melanoma of the nose.

Lobular to Lobule: Metastatic Breast Carcinoma to Olfactory Neuroblastoma

Tumor-to-tumor metastasis (TTM) is a rare, but well-described phenomenon occurring in patients with multiple synchronous or metachronous primary malignancies. Olfactory neuroblastoma (ONB) is a rare malignant, neuroectodermal sinonasal tract tumor that occurs within the ethmoid sinus involving the cribriform plate. Very few cases of ONB have been documented to metastasize to other primary malignancies, but the reverse scenario is exceptional. During an evaluation for anosmia, a right nasal polyp was identified on imaging and endoscopy in a 66-year-old woman, with a polypectomy performed. Histologic examination showed classical features of a low-grade olfactory neuroblastoma, but within the tumor were isolated epithelioid cells which were strongly pancytokeratin immunoreactive. Review of the clinical history revealed lobular breast carcinoma treated 10 years earlier. Further evaluation with immunohistochemistry showed strong and diffuse nuclear estrogen and progesterone receptor reactivity, along with GATA3. These results confirmed TTM of an invasive lobular breast carcinoma to ONB. By employing a limited immunohistochemistry panel for all small round blue cell tumors that includes pancytokeratin, p40, S100 protein, SOX10, synaptophysin, desmin, CD99, and CD45, one is able to more accurately diagnose the classical tumor types, while also showing potentially unusual tumor features or exceptionally rare events like metastatic lobular breast carcinoma to ONB.

Epstein-Barr Virus-Associated Smooth Muscle Tumors of Larynx: A Clinicopathologic Study and Comprehensive Literature Review of 12 Cases

Laryngeal mesenchymal neoplasms are rare, with smooth muscle tumors comprising a small subset. Specifically, Epstein-Barr virus (EBV)-associated smooth muscle tumors are exceptionally rare, lacking a comprehensive evaluation of their clinical and histologic features. Two patients (a 59 year old male and 51 year old female) had received renal transplants 156 and 240 months, respectively prior to onset of laryngeal symptoms. Supraglottic polypoid masses were identified and removed conservatively. Histologically, the tumors were hypercellular, showing alternating light and dark areas, the latter composed of primitive appearing round cells, while a more characteristic spindled tumor cell population was noted in the remaining areas. Cytoplasmic vacuoles were noted adjacent to the nucleus. There was no tumor necrosis or pleomorphism, but increased mitotic figures (11-12/2 mm²) were seen, without atypical forms. The tumor cells were strongly immunoreactive with smooth muscle actin and smooth muscle myosin heavy chain and with Epstein-Barr virus encoded RNA (EBER) by in situ hybridization. These patients were reviewed in the context of a thorough English literature review, which demonstrates a wide age range at presentation without a sex predilection, but with most patients from specific ethnic groups (Chinese, Thai, Pilipino). Three-quarters of patients are part of multifocal disease and the majority are post-renal transplantation patients. Conservative management seems to yield the best overall outcome for these indolent tumors. In conclusion, EBV-associated smooth muscle tumors should be considered in any immunocompromised patient with a head and neck smooth muscle tumor, especially when EBER is documented by in situ hybridization. Conservative management may be employed, even when multifocal tumors are documented.

Surgical Margin Status and Survival Following Resection of Sinonasal Mucosal Melanoma

OBJECTIVES

Sinonasal mucosal melanoma (SNMM) is an aggressive cancer usually managed with surgical resection. This study evaluates the impact of treatment modality and positive surgical margin (PSM) on survival following resection of SNMM.

STUDY DESIGN

Retrospective study of a national cancer registry.

METHODS

The National Cancer Database was queried for cases of SNMM from 2010 to 2015. Data regarding patient demographics, tumor staging, and treatment modality were obtained. Survival rates were compared by margin status: PSM, negative (NSM), and no operation (0SM) using Kaplan-Meier analysis and log rank test.

RESULTS

A total of 446 patients met inclusion criteria. Most cases were elderly (>66 years-old) (67.3%), female (54.3%), and white (89.5%). Cases of SNMM most commonly involved the nasal cavity (81.6%), were Stage 3 (60.0%), and underwent surgical resection at an academic center (65.0%). NSM and PSM were present in 59.0% and 26.9% of cases, respectively, while 14.1% of cases did not undergo surgical resection (0SM). Factors predictive of PSM included resection at a community hospital (OR 2.47) and Stage 4 disease (OR 2.07). The 2-year survival rates were 72.1% (95% CI 69.4-75.4%), 36.3% (95% CI 22.0-48.9), and 16.0% (95% CI 8.2-25.4%) for NSM, PSM and 0SM, respectively. Survival was statistically significant between NSM and PSM (Log rank <0.001) but not between 0SM and PSM (Log rank = 0.062).

CONCLUSION

Our study emphasizes the need for NSM for SNMM as PSM did not demonstrate any significant improvement in survival when compared to 0SM. Our findings suggest that cases of SNMM are best managed at academic centers.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Sinonasal mucosal melanoma: treatment strategies and survival rates for a rare disease entity : A single center experience and review of literature

Background

Sinonasal mucosal melanoma (SNMM) is a rare disease entity comprising 0.4–1.3% of all melanomas. Surgery with free margins has been the primary treatment over decades. Neither the addition of radiotherapy nor chemotherapy could significantly improve outcome rates of this devastating malignancy. This study presents our clinical experience with SNMM over a 19-year period and summarizes the current body of literature on SNMM.

Methods

This retrospective analysis included 12 patients with SNMM treated from 2001 to 2019 at an academic center. Additionally, a literature review of the last 29 years on treatment and survival data of SNMM was conducted.

Results

Main initial symptoms were epistaxis and nasal obstruction. Of the patients 9 underwent endoscopic surgery, 6 received adjuvant therapy. 3 patients who did not undergo surgery, received chemoradiotherapy, radiotherapy alone, and chemotherapy alone, respectively. At the time of diagnosis 2 patients had distant metastases and 4 patients developed distant metastases during the course of the disease. Mean overall survival (OS) was 30.6 months, 3‑year and 5‑year OS were 25%, and 18.2%, respectively.

Conclusion

Unspecific symptoms and hidden anatomic locations lead to delayed diagnosis and increased rates of metastatic dissemination. Distant metastasis is the main treatment failure in SNMM. Surgery with free margins remains the primary treatment for SNMM. Adjuvant radiotherapy might improve local control in individual cases but efficient systemic therapy is needed to improve outcome rates. To evaluate and define more effective targeted treatment options and improve outcome rates, homogeneous data and prospective multicentric analysis are needed.

Rare Diseases of the Nose, the Paranasal Sinuses, and the Anterior Skull Base

Due to their low incidence and thus resulting limited diagnostic criteria as well as therapeutic options, rare diseases of the nose, the paranasal sinuses, and the anterior skull base are a significant challenge. The value as of which a disease has to be considered as rare amounts to a maximum of 5 patients per 10 000 people. Within these diseases, however, there are extreme differences. Some rare or orphan diseases like for example the inverted papilloma belong to regularly diagnosed and treated diseases of larger departments of oto-rhino-laryngology whereas other rare diseases and malformations have only been described in less than 100 case reports worldwide. This fact emphasizes the necessity of bundling the available experience of diagnostics and therapy. The present article gives an overview about rare diseases of the nose, the paranasal sinuses, and the anterior skull base from the field of diseases/syndromes of the olfactory system, malformations of the nose and paranasal sinuses, ventilation and functional disorders as well as benign and malignant tumors. The classification and data on diagnostic and therapeutic options were established based on the current literature.

Matched analysis of the prognosis of amelanotic and pigmented melanoma in head and neck

Background: The prognosis of mucosal melanoma is poor, and the difference in clinical prognosis between patients with and without pigment needs further study.Aim: To analyze data with head and neck mucosal melanoma, and compare the prognosis of patients with and without pigment.Material and methods: The patients of amelanotic melanoma were matched with pigmented type according to age, sex, stage, location of disease, treatment history, tobacco and alcohol history. The Kaplan-Meier and Cox proportional risk regression model was used for analyzation.Results: 46 patients of amelanotic melanoma and 46 of pigmented type were included in this study. The overall survival rate and progression-free survival rate of patients with pigmented melanoma were higher than in patients with amelanotic melanoma (HR = 0.533, p = .035, 95% CI = 0.296-0.957; HR = 0.530, p = .034, 95% CI = 0.294-0.953, respectively), and the risk of distant metastases in patients with amelanotic melanoma was significantly higher than that in patients with pigmented melanoma (HR = 0.474, p = .046, 95% CI = 0.228-0.987).Conclusions and significance: The prognosis and disease-free survival of amelanotic melanoma is worse than for the pigmented type group. More identifying the differences in clinical characteristics will help to further individualized treatment decisions.

The Role of Adjuvant Treatment in Craniofacial Malignancy: A Critical Review

Background: Tumors originating from the craniofacial region usually present in a locally advanced stage with frequent involvement of adjacent sites and have a strong tendency for local recurrence in the absence of adjuvant therapy, even when the original surgical resection was presumed to be radical. In the past decades, several advances in the radiological diagnosis and treatment of craniofacial malignancies have been introduced. There are, however, no randomized trials that define the optimal multimodal treatment of these tumors because of their rarity as well as heterogeneity in both histology and site of origin. The aim of this study was to conduct a critical review of the role of adjuvant therapy in the treatment of craniofacial malignancy. Method: We conducted a critical review of the past and contemporary literature available, focusing on adjuvant oncological treatments of the most common craniofacial malignancies. Results: Preoperative radiotherapy can have a documented role in the treatment of olfactory neuroblastoma and soft tissue sarcoma, while preoperative chemotherapy can be advocated in the treatment of sinonasal undifferentiated carcinoma, neuroendocrine carcinoma, olfactory neuroblastoma, and craniofacial sarcoma (both soft-tissue and high-grade osteosarcoma). Postoperative radiotherapy has a well-established role in the treatment of most craniofacial malignancies. The role of postoperative chemotherapy is unclear in most histologies, but is commonly used during the treatment of well-selected cases of paranasal sinus carcinoma, olfactory neuroblastoma, mucosal melanoma, soft tissue sarcoma and high-grade craniofacial osteosarcoma. Discussion: Alongside developments in surgery, there have also been improvements in diagnostics, radiotherapy, and chemotherapy. Implementation of novel radiation techniques allows delivery of higher radiation doses while minimizing irradiation-related morbidity. Better understanding of tumor biology allows the construction of more complex treatment strategies, incorporating adjuvant chemotherapy either pre- or postoperatively. In the era of personalized targeted therapy, rapid strides are being made to identify specific tumor-targets for use of novel biologic agents, with the potential to change current management paradigms.

Sinonasal mucosal melanoma: a 10-year experience of 36 cases in China

Background

Sinonasal mucosal melanoma (SNMM) is a rare tumor with a poor prognosis. This study aimed to assess the clinical and imaging features, progression, treatment, and possible prognostic factors of SNMM.

Methods

Thirty-six patients with SNMM were retrospectively reviewed in the Department of Otolaryngology & Head and Neck Surgery of Xinhua Hospital from January 2008 to December 2017.

Results

The age of the first diagnosis was 67.4±10.8 years; the most common clinical symptoms included epistaxis, nasal obstruction, headache, and facial pain. Most tumors originated in the nasal cavity (63.9%) and at stage IV (77.8%). Melanin in melanoma showed typical signal intensity on magnetic resonance imaging (MRI), T1WI had high signal while T2WI had low signal. 41.6% of patients had the typical MRI findings. Treatment included surgery, surgery with radiotherapy, and radiotherapy only. The follow-up time ranged from 4 to 96 months, with a median time of 22 months, 1-, 3-, and 5-year OS is 80.6%, 36.1%, and 13.9%, respectively. The 3-year OS was better in cases in the T3 stage than the T4 stage (P=0.02). However, tumors that originated from the paranasal sinus had a poorer prognosis than the nasal cavity (P=0.04). The cases receiving postoperative radiotherapy showed poorer prognosis (P=0.02). Other factors were not found to be associated with prognosis, including gender, age, lymph node metastasis, distant metastasis, computed tomography (CT) enhancement, and typical MRI findings.

Conclusions

The SNMM was a devastating tumor with poor outcomes; most cases were diagnosed at late stages, which may account for poor prognosis. Tumors with melanin feature MRI findings do not have a better prognosis. The treatment of postoperative radiotherapy is still controversial.

Oral Amelanotic Melanomas: Clinicopathologic Features of 8 Cases and Review of the Literature

Mucosal melanomas are aggressive tumors, rarely observed in the oral cavity. The diagnosis is based on the clinical and microscopical features. Often these tumors had variable amounts of melanin pigmentation. However, when melanin is absent, the tumors are denominated amelanotic, presenting a tendency to misdiagnosis and delayed treatment. The aim of this study was to describe the clinicopathologic features of a series of oral amelanotic melanomas (OAM). Records of all cases of OAM were retrospectively retrieved from oral pathology services from January 2002 to January 2019. Data regarding the clinical features, morphological aspects, immunohistochemical reactions, treatment, and follow-up status were collected. Eight cases of OAM were included, 6 in men and 2 in women (ratio of 3:1) ranging in age from 33 to 77 years (mean 53.6 years). Clinically, the tumors presented as masses or ulcerated swellings. The most common intraoral locations of the tumors were gingiva and palate. Cervical lymph node metastasis was detected in 3 patients at the first examination. All but one patient died from complications of the tumors after a mean follow-up period of 8.5 months. In conclusion, OAM is a very aggressive malignant tumor, and when melanin is absent, an immunohistochemical panel comprising S100, melan A, HMB45, and SOX10 should be performed.

Variable Expression of S100 Protein in Sinonasal Malignant Mucosal Melanoma: A Potential Diagnostic Pitfall

Sinonasal malignant mucosal melanoma (SNM) is a rare, aggressive malignancy. The diagnosis of SNM is often quite challenging due to anatomical limitations, frequent lack of pigmentation, variable histologic appearances, and aberrant differentiation (e.g., positivity for cytokeratin, desmin, or neuroendocrine markers). S100 protein is routinely used as a standard screening marker for SNM, but it may lack optimal sensitivity. Our objective was to study the extent of immunohistochemical expression of S100 protein in SNM, and determine its diagnostic value by comparing it to a newer melanoma marker, SOX10. Twenty-three cases of sinonasal MMM were retrieved from the archival files of the Department of Pathology at UT Southwestern Medical Center. The patients included 14 men and 9 women, and ranged from 36 to 90 years (mean 64.9 years). Sections from blocks of formalin-fixed, paraffin-embedded tissue were used for immunohistochemical analysis with S100 protein and SOX10. The extent and intensity of immunostaining was recorded, and H-score was calculated. For a subset of negative or focally positive cases, S100 protein was repeated at a high-volume reference laboratory. S100 protein immunoexpression was quite variable in the SNM cases, with H-scores ranging from 0 to 300 (mean 123). While 11 of 23 cases exhibited strong and diffuse staining (H-score > 100) as expected for melanoma, 7 were weak and/or focal (H-score 1-100), and 5 were completely S100 protein-negative. For 10 cases, the negative or focal results were confirmed by reference laboratory staining. In contrast, all 23 SNM cases were diffusely and strongly positive for SOX10 (H-scores 210-300, mean 296). Our study demonstrated that S100 protein immunoexpression is extremely variable in SNM. Weak or even absent S100 protein staining is not uncommon in SNM, and should not dissuade pathologists from that diagnosis. Our data demonstrates that S100 protein is insufficiently sensitive to be used as a screening marker for SNM, but that SOX10 is consistently and robustly positive, and should therefore replace S100 protein for that purpose. Indeed, for any high-grade sinonasal tumor, pathologists must have a low threshold for utilizing additional markers to exclude the possibility of SNM.

Sinonasal amelanotic melanoma with neuroendocrine differentiation: a diagnostic conundrum

Mucosal malignant melanoma of the head and neck (HN) is a rare and aggressive neoplasm which constitutes only 1% of all melanomas. Neuroendocrine differentiation is an extremely unusual phenomenon in mucosal melanomas, of which five cases have been reported. We report a rare case of a 63-year-old female who developed sinonasal amelanotic melanoma with immunohistochemical expression of neuroendocrine markers, presenting a diagnostic dilemma. Ultrastructural evidence of melanosomes and neurosecretory granules aided in arriving at the diagnosis. Aberrant immunoexpression of neuroendocrine markers, particularly in an amelanotic melanoma, has critical diagnostic implications, as various malignancies with undifferentiated histomorphology occur at this site, many of which stain positively with neuroendocrine markers. We discuss the differential diagnoses and recommend a high index of suspicion so as not to miss the diagnosis of mucosal melanoma at this location.

SF3B1, NRAS, KIT, and BRAF Mutation; CD117 and cMYC Expression; and Tumoral Pigmentation in Sinonasal Melanomas: An Analysis With Newly Found Molecular Alterations and Some Population-Based Molecular Differences

Sinonasal melanomas encompass melanoma arising in the nasal cavity and paranasal sinuses. Despite recent advances in tumor genomics, correlation between mutational status and protein expression with prognosis and tumor pigmentation has not been carried out in sinonasal melanomas. Ninety-five sinonasal melanomas from 95 patients were included. As per univariate analyses, age was the only variable that significantly correlated with progression-free survival. SF3B1, NRAS, KIT, and BRAF mutations were documented in 7% (5/72), 22% (16/72), 22% (16/72), and 8% (6/72) of cases, respectively. Comutation was detected in 6 cases: NRAS and KIT in 2 cases; NRAS and BRAF in 2 cases; SF3B1, KIT, and BRAF in one case; and SF3B1, NRAS, and KIT in one case. Correlations approaching statistical significance were observed between BRAF mutation status and poorer overall survival and progression-free survival (log-rank P-values=0.054 and 0.061). Increased CD117 expression (33%, 29/88) and decreased nuclear cMYC expression (40%, 39/84) significantly correlated with cytoplasmic pigmentation. Several SF3B1, NRAS, and KIT mutations not previously documented in sinonasal melanomas were detected in our series, suggesting a potential role for targeted therapies. A similar frequency of SF3B1, NRAS, and KIT mutations was noted in Asian cases, whereas NRAS, KIT, and BRAF mutations were predominant in the United States and European cases; however, the number of included cases was small. The significant association between CD117 and cMYC expression with increased cytoplasmic pigmentation in our series suggests that the pigmented morphologic appearance of sinonasal melanomas could be attributed to the underlying oncogenic mutations and metabolic interaction.

Diagnostic traps awaiting the head/neck pathologist: "Cytoplasm-poor" neoplasms

CONTEXT

Beyond squamous carcinoma, a variety of diagnostically challenging neoplasms arise within various head and neck sites. This is particularly the situation with neoplasms where little cellular cytoplasm is present to assist the pathologist in categorizing such lesions.

OBJECTIVE

To highlight diagnostic pitfalls that accompanying neoplasms composed primarily of 'cytoplasmically-poor' cells. These pitfalls include morphologic and immunohistochemical traps that emerge from this class of neoplasms.

DATA SOURCES

Selection of pathologic specimens from the author's personal files, and literature review.

CONCLUSIONS

Interpretative pitfalls regarding the histopathology and immunophenotype of small 'cytoplasmically-poor' neoplasms are a diagnostic hazard in head and neck surgical pathology practice, and require knowledge of histomorphologic plasticity and aberrant immunophenotyping.

Current concepts in advanced sinonasal mucosal melanoma: a single institution experience

PURPOSE

To present outcome measures of sinonasal mucosal melanoma (SMM) patients with particular focus on current radiological and therapeutic options, especially in the non-curative setting (immunotherapy).

METHODS

Retrospective study on SMM patients treated at our institution between January 1992 and December 2018.

RESULTS

FDG-PET/MRI has emerged as the new hybrid imaging modality, addressing the need for high local tissue contrast in the paranasal sinuses and the skull base, while allowing for whole-body staging in search for distant metastases, including the brain. Primary treatment protocols consisted of tumor resection in 30/34 patients (88%), palliative radiation therapy (RT) in 3/34 patients (9%) and best supportive care therapy in 1/34 patient (3%). Of all the initially operated patients, 25/30 patients (83%) received adjuvant RT. A total of 9/34 patients (26%) was treated with immunotherapy after the previous combined therapy. For patients treated in curative intention, we observed a 1-year overall survival (OS) of 60% (18/30 patients) and a 3-year OS of 40% (12/30 patients). For patients treated with immunotherapy, median progression-free survival (PFS) was 5 months (IQR 0-13.75), with a maximum PFS of 16 months (combination of nivolumab and ipilimumab). However, there was no difference in OS in patients treated with immunotherapy vs. no immunotherapy (log rank 0.99).

CONCLUSIONS

Sinonasal mucosal melanoma is a highly aggressive tumor, requiring multimodal therapy and developing a substantial incidence of distant metastases. The introduction of FDG-PET/MRI offers new possibilities in the radiological assessment of the tumor and immunotherapy has altered the management in the non-curative setting, resulting in a substantial progression-free survival in selected cases.

Expression of mitochondrial dynamics markers during melanoma progression: Comparative study of head and neck cutaneous and mucosal melanomas

BACKGROUND

Head and neck mucosal melanomas (MMs) are rare tumors with adverse outcomes and poorer prognoses than their more common cutaneous counterparts (cutaneous melanomas-CMs). Few studies have compared the expression of mitochondrial dynamic markers in these tumors. This study aimed to assess the correlations of mitochondrial markers with melanoma progression and their potential as predictors of lymph node involvement and distant metastasis.

METHODS

Immunohistochemistry against anti-mitochondrial (AMT), dynamin-related protein 1 (DRP1), mitochondrial fission protein 1 (FIS1), mitofusin-1 (MFN1), and mitofusin-2 (MFN2) antibodies was performed in 112 cases of head and neck CM and MM. A Cox regression multivariate model was used to assess the correlation of AMT, FIS1, and MFN2 expressions considering the risk for nodal and distant metastasis.

RESULTS

All markers studied presented higher staining in tumor cells than normal adjacent tissues. Higher mitochondrial content was observed in MM than in CM, and it was significantly associated with nodal metastasis in oral melanomas. Both FIS1 and DRP1 expressions were related to advanced Clark's levels in CM, and they were overexpressed in oral melanomas. Moreover, increased immunoexpression of MFN2 was significantly associated with a higher risk of metastasis in CM, and it was also overexpressed in sinonasal melanomas.

CONCLUSIONS

Our results suggest that mitochondrial fission and fusion processes can play an important role during multiple stages of tumorigenesis and the development of nodal and distant metastasis in cutaneous and mucosal melanomas.