Review: mucosal melanoma of the head and neck

From apparent pseudoprogression to durable complete remission of expansile destructive sinonasal mucosal melanoma under pembrolizumab after primary endoscopic resection: A case report

Head and neck mucosal melanoma is a rare but highly aggressive malignant tumor that usually has a poor prognosis. We describe a 53-year-old male patient, having no any medical history, with left maxillary sinus mucosal melanoma causing bilateral lung metastasis. Rapid tumor regrowth was observed on the 49th day after radical tumor resection. Subsequent pembrolizumab immunotherapy initially elicited pseudoprogression, for which add-on radiation therapy was carried out during maintenance pembrolizumab. A gradual decrease in tumor volume and complete remission were observed by a series of magnetic resonance imaging scans and lung windows of a computer tomography scan of chest. At the 29-month follow-up, the patient was rendered disease-free. In conclusion, head and neck mucosal melanoma may regrow rapidly after surgical resection and pseudoprogression could be frightening during immunotherapy. Subsequent single-agent pembrolizumab plus localized radiation therapy aiming to release more tumor antigens may offer the possibility of long-term remission.

Efficacy of immune checkpoint inhibitor treatment for head and neck mucosal melanoma recurrence in patients treated with carbon-ion radiotherapy

BACKGROUND

Carbon-ion radiotherapy (C-ion RT) is effective for head and neck mucosal melanoma (HN-MM), including radioresistant mucosal melanoma. Melanoma also responds effectively to immune checkpoint inhibitors (ICIs). Data on the efficacy and safety of ICIs for HN-MM are insufficient.

AIMS

To analyze the efficacy and safety of ICI salvage therapy in patients with HN-MM recurrence after C-ion RT.

METHODS AND RESULTS

This retrospective study analyzed the medical records of 52 patients with HN-MM treated with C-ion RT between 2012 and 2020. A dose of 57.6 or 64.0 Gy (relative biological effectiveness) was provided in 16 fractions. The primary endpoint was 3-year overall survival (OS) rate. The median follow-up time was 26.8 months for all patients. A total of 29 patients had local recurrence or distant metastasis, and 16 patients who received ICI therapy. The 3-year OS rate in the ICI group (n = 16) and best supportive care group (n = 13) were 53.8% and 0.0%, respectively (p = 0.837); the difference was not statistically significant. There were no deaths after 1 year among patients who underwent ICI therapy. No adverse events associated with C-ion RT were related to or exacerbated by ICI.

CONCLUSION

ICI salvage therapy is effective and safe for patients with HN-MM recurrence after C-ion RT.

Impact of adjuvant therapies following surgery for anal melanoma

BACKGROUND

Anal melanoma is rare. Surgery is standard of care for non-metastatic disease. There are limited data supporting adjuvant therapy. We sought to examine the impact of adjuvant radiation, chemotherapy and immunotherapy on survival.

METHODS

The National Cancer Database was queried. Factors associated with overall survival were examined by Kaplan-Meier and Cox proportional hazards analyses. Patients were grouped by treatment regimen.

RESULTS

450 patients had complete treatment data: surgery alone (63.8%), surgery + radiation (14.9%), surgery + chemotherapy (7.6%), surgery + immunotherapy (9.6%) and non-surgical treatment (4.2%). Median survival was 27.2 months. Node-positive patients had worse survival than node-negative (22.4 vs. 36.8 months; p = 0.0002). Non-surgical treatment yielded worse survival than any surgery-inclusive regimen (10.4 vs. 27.8 months; p = 0.0002). No adjuvant modality conferred a survival advantage. By multivariate analysis, increasing age (HR/1 year = 1.02, p = 0.012) and node positivity (HR = 2.10, p = 0.0002) negatively impacted survival.

CONCLUSION

Adjuvant therapy for non-metastatic anal melanoma does not appear to influence survival.

Prognosis of Distant Metastatic Sites in Anterior Skull Base Malignancies

Objective This study aimed to provide information regarding the prognosis of patients presenting with metastatic anterior skull base malignancies based upon histology and site of distant metastasis (DM).

Patients and Methods The National Cancer Database was queried for patients with anterior skull base malignant neoplasms with DM.

Outcomes Prognosis was compared between site of DM and tumor histologies. A multivariable Cox proportional hazards model was used to identify prognostic factors for overall survival (OS).

Results A total of 481 patients were identified. Lung was the most common site of DM (24.9%), followed by bone (22.2%), liver (5.6%), and brain (2.5%). Lung was the most common site for squamous cell carcinoma (SCCa) (28.3%), melanoma (37.7%), and adenoid cystic carcinoma (ACC; 31.4%). The median survival for patients presenting with metastatic disease regardless of tumor histology was 9.0 months (95% confidence interval [CI]: 8.2–10.3), and patients with metastasis to the liver had the best median survival at 15.5 months (95% CI: 10.5–25.6). The median survivals for the most common histologies, SCCa, melanoma, and ACC were 8.2 months (95% CI: 5.5–10.2), 10.5 months (95% CI: 8.7–14.1), and 15.0 months (95% CI: 11.1–61.1), respectively. Multivariable analysis demonstrated worse overall survival (OS) for older patients, higher Charlson-Deyo comorbidity scores, and tumors with higher grade and T stage. Compared with metastasis to bone, lung metastasis had better OS on multivariable analysis (hazard ratio [HR]: 0.70, 95% CI: 0.51–97). Adenoid cystic carcinoma had improved OS compared with SCCa (HR: 0.62, 95% CI: 0.39–99).

Conclusion Tumor histology, metastatic sites, and several disease factors affected prognosis in anterior skull base malignancies with DM.

Regional disease control in sinonasal mucosal melanoma: Systematic review and meta-analysis

PURPOSE

To systematically analyze the regional disease control after sinonasal mucosal melanoma (SNMM) primary treatment.

METHODS

The study was performed according to the PRISMA guidelines searching on Scopus, PubMed/MEDLINE, Cochrane Library, and Google Scholar databases.

RESULTS

A total of 15 studies with 936 patients (median age: 68.0 years, IQR 65-71) were included. Overall, the cumulative regional recurrence rate (RRR) was 18.4% (n = 917, 99% CI: 14.0%-23.4%), with a median follow-up of 30.0 months (n = 765, IQR 22.0-37.0). The RRR in clinical node negative patients was 17.0% (99% CI: 12.2%-22.5%), with a median follow-up of 22.0 months (n = 327, IQR 21.5-31.5).

CONCLUSIONS

The RRR of SNMM after primary treatment is not to be neglected. Further prospective studies should be encouraged to clarify if elective treatment of the neck could be recommended at least in a subgroup of patients.

Mucosal Melanoma of the Head and Neck: A Retrospective Review and Current Opinion

Introduction: Head and Neck Mucosal Melanoma (HNMM) is an uncommon malignancy that arises in decreasing order in the nasal cavity, the paranasal sinuses, and the oral cavity. Although radical surgery followed by eventual radiotherapy is acknowledged as the mainstay treatment, patients with advanced stages or multi-focal tumors benefit from new systemic therapies. We wish to share our experience with these treatments and review the current literature. Materials and Methods: We present a case review of every patient treated in our center for an HNMM over the past 10 years, including every patient treated in our center for an HNMM over the past 10 years. We analyzed clinical characteristics, treatment modalities, and outcomes. Results: We included eight patients aged from 62 to 85 years old. We found six MM in the nasal cavity, one in the sphenoidal sinus, and one in the piriform sinus. Six patients underwent endoscopic surgery with negative margins, six underwent radiotherapy with variable modalities. Immunotherapy or targeted therapy was given in cases extensive tumors without the possibility of a surgical treatment or in two patient as an adjuvant treatment after R0 surgery. The three-year overall survival was 50%, and three patients (37.5%) are in remission. Conclusions: HNMM is associated with poor oncologic outcomes regarding the concerned patients of our review, as reported in the literature. New treatments such as immunotherapies or targeted therapies have not significantly changed the prognosis, but they may offer new interesting perspectives. Our small series of cases seems to confirm that surgical resection with negative margins improves overall survival.

Pevonedistat targeted therapy inhibits canine melanoma cell growth through induction of DNA re-replication and senescence

MLN4924 (pevonedistat) is a potent and selective NEDD8-activating enzyme (NAE) inhibitor. The NEDD8-regulated neddylation system is responsible for the regulated degradation of intracellular proteins with important cellular functions in cancer cell growth, apoptosis, angiogenesis and metastasis. In human melanoma, inhibition of NAE results in induction of DNA re-replication, S phase cell cycle arrest, DNA damage and apoptosis. The study aimed to assess the anti-cancer effect of MLN4924 on canine malignant melanoma cell lines and patient samples and to elucidate the underlying mechanisms. Canine melanoma cell lines and primary patient samples were evaluated for cell viability after incubation with varying concentrations of MLN4924 or dimethyl sulfoxide. Apoptosis, cell proliferation and senescence assays were performed to address underlying mechanisms of MLN4924-mediated anti-tumour effects. Gene expression of seven previously identified deregulated genes in human melanoma was compared in sensitive vs resistant samples. MLN4924 treatment significantly reduced the viability of canine melanoma cell lines and primary samples in a dose- and time-dependent manners. MLN4924 promoted cell apoptosis and inhibited cell growth through induction of DNA re-replication and cell senescence. While the majority of canine melanoma samples demonstrated sensitivity at nanomolar ranges, some samples were resistant to the treatment. Modulation of P21 levels correlated with canine melanoma cell sensitivity. These results provided justification for further exploration of MLN4924 as a treatment of canine melanoma.

Prospective clinical trial of masitinib mesylate treatment for advanced stage III and IV canine malignant melanoma

OBJECTIVE

To investigate efficacy of masitinib mesylate for the treatment of advanced malignant melanoma in dogs.

MATERIALS AND METHODS

Prospective clinical trial on 17 dogs with stage III and IV malignant melanoma (two digital, one anal and 14 oral mucosal). Only dogs with advanced gross disease for which the owner declined conventional treatment or dogs with progressive tumour despite conventional treatment were included.

RESULTS

There was a partial response in two dogs, stable disease in seven and tumour progression in eight dogs. Median survival time for all 17 dogs was 119 days (range 21-255). Masitinib was generally well-tolerated but grade 2 anaemia, grade 1 neutropenia, grade 1 diarrhoea and grade 2 anorexia were observed in one dog each.

CLINICAL SIGNIFICANCE

There was only mild effectiveness in end-stage disease, indicating that masitinib mesylate is not an appropriate sole-agent option for treatment of advanced malignant melanoma in dogs.

Carbon-ion radiotherapy combined with chemotherapy for head and neck mucosal melanoma: Prospective observational study

This study aimed to evaluate the efficacy of carbon-ion radiotherapy in combination with chemotherapy using dacarbazine, nimustine, and vincristine (DAV therapy) in mucosal melanoma. Twenty-one patients with clinically localized mucosal melanoma of the head and neck were enrolled. The primary endpoint was 3-year overall survival (OS). Secondary endpoints included local control, progression-free survival (PFS), and adverse event occurrence. Carbon-ion radiotherapy with a dose of 57.6-64.0 Gy (relative biological effectiveness) in 16 fractions was delivered concurrently with DAV therapy, and 2 cycles of adjuvant DAV therapy were administered every 6 weeks. The median follow-up periods were 15.5 months for all patients, and 31.2 months for 12 surviving patients. All patients had locally advanced T4a or T4b disease in the rhino-sinus area. In 16 patients (76.2%), 3 cycles of planned DAV therapy were completed. The 3-year OS and PFS rates were 49.2% and 37.0% respectively. The 3-year local control rate was 92.3%. Eleven patients (52%) developed distant metastasis, which was the most frequent pattern of the first failure. Commonly presenting acute grade 2-3 toxicities associated with radiotherapy and chemotherapy were mucositis (11 patients [53%]) and leukopenia (9 patients [43%]), which improved with conservative therapy. None of the patients developed grade 3 or greater late toxicities. Carbon-ion radiotherapy in combination with DAV therapy led to excellent local control for advanced mucosal melanoma within acceptable toxicities. The efficacy of additional DAV therapy in improving survival was weaker than expected as distant metastases still occurred frequently. Trial registration no. UMIN000007939.

Clinically node-negative head and neck mucosal melanoma: An analysis of current treatment guidelines & outcomes

OBJECTIVES

To analyze head and neck mucosal melanoma (MM) treatment patterns, and their association with survival, relative to National Comprehensive Cancer Network (NCCN) guidelines.

MATERIAL & METHODS

Adult head and neck MM patients with clinically-staged T3/4aN0 disease were identified in a retrospective analysis of the National Cancer Database (2010-2014) and stratified into sinonasal cavity (SN) and oral cavity, oropharynx, larynx, or hypopharynx (non-SN) cohorts.

RESULTS

We identified 353 SN and 79 non-SN MM cases. The majority of patients were treated with surgery (SN: 92.4%; non-SN 84.8%), within NCCN guidelines. Treatment within the non-SN MM NCCN recommendation of elective neck dissection (END) was approximately 26.6%. END is not recommended for SN MM and was not performed in 91.5% of cases. Radiotherapy (RT) is recommended in both SN and non-SN MM and was utilized in 63.5% of SN patients and 46.8% of non-SN patients. END was not independently associated with OS compared to surgery alone (SN HR: 1.350 [95% CI: 0.733-2.485]; non-SN HR: 3.460 [95% CI: 0.912-13.125]). RT was independently associated with improved OS in SN MM cases (HR: 0.679 [95% CI: 0.479-0.963]), but not in non-SN MM cases (HR: 0.824 [95% CI: 0.331-2.051]).

CONCLUSION

The majority of patients with head and neck MM are not treated within NCCN guidelines. The use of recommended END in non-SN patients is low. Similarly, adjuvant RT utilization is low. Our analysis shows that while greater use of RT may increase survival rates in this disease, the utility of END is unclear.

MicroRNA-23a-3p Inhibits Mucosal Melanoma Growth and Progression through Targeting Adenylate Cyclase 1 and Attenuating cAMP and MAPK Pathways

Mucosal melanoma (MM) is the second most common melanoma subtype in Asian populations. Deregulation of microRNAs (miRNAs) has been extensively investigated in various cancers, including cutaneous melanoma. However, the roles of miRNAs in MM are unclear. In this study, we carried out miRNA profiling in MM, and we investigated the clinical and biological roles of miR-23a-3p in MM.

Methods: miRNA expression in MM was profiled by miRNA microarray analysis. The expression of miR-23a-3p was quantitated by qRT-PCR in a cohort of 117 patients with MM, and its prognostic significance was evaluated. The biological effect of miR-23a-3p was demonstrated by both in vitro and in vivo studies through ectopic expression of miR-23a-3p. The target gene of miR-23a-3p and molecular pathway influenced by it was characterized using in silico target prediction tools, dual luciferase reporter assays, knockdown, and rescue experiments.

Results: Microarray and qRT-PCR results showed that the miR-23a-3p level was substantially lower in MM, and low miR-23a-3p expression was significantly associated with poor outcomes. Ectopic expression of miR-23a-3p suppressed MM cell proliferation, migration, invasion, and tumorigenicity, indicating that miR-23a-3p has a tumor-suppressive role in MM. Mechanistic investigations identified adenylate cyclase 1 (ADCY1) as a direct target of miR-23a-3p in MM, and knockdown of ADCY1 recapitulated all the phenotypic characteristics of miR-23a-3p overexpression. Targeting of ADCY1 by miR-23a-3p resulted in the suppression of cyclic adenosine monophosphate (cAMP) and mitogen-activated protein kinase (MAPK) signaling pathways.

Conclusions: Our data highlight the molecular etiology and clinical significance of miR-23a-3p in MM and reveal its major target and biological function. miR-23a-3p may represent a new prognostic biomarker or therapeutic target in MM.

Isolation and characterization of two canine melanoma cell lines: new models for comparative oncology

BACKGROUND

Metastatic melanoma is one of the most aggressive forms of cancer in humans. Among its types, mucosal melanomas represent one of the most highly metastatic and aggressive forms, with a very poor prognosis. Because they are rare in Caucasian individuals, unlike cutaneous melanomas, there has been fewer epidemiological, clinical and genetic evaluation of mucosal melanomas. Moreover, the lack of predictive models fully reproducing the pathogenesis and molecular alterations of mucosal melanoma makes its treatment challenging. Interestingly, dogs are frequently affected by melanomas of the oral cavity that are characterized, as their human counterparts, by focal infiltration, recurrence, and metastasis to regional lymph nodes, lungs and other organs. In dogs, some particular breeds are at high risk, suggesting a specific genetic background and strong genetic drivers. Altogether, the striking homologies in clinical presentation, histopathological features, and overall biology between human and canine mucosal melanomas make dogs invaluable natural models with which to investigate tumor development, including tumor ætiology, and develop tailored treatments.

METHODS

We developed and characterized two canine oral melanoma cell lines from tumors isolated from dog patients with distinct clinical profiles; with and without lung metastases. The cells were characterized using immunohistochemistry, pharmacology and genetic studies.

RESULTS

We have developed and immunohistochemically, genetically, and pharmacologically characterized. Two cell lines (Ocr_OCMM1X & Ocr_OCMM2X) were produced through mouse xenografts originating from two clinically contrasting melanomas of the oral cavity. Their exhaustive characterization showed two distinct biological and genetic profiles that are potentially linked to the stage of malignancy at the time of diagnosis and sample collection of each melanoma case. These cell lines thus constitute relevant tools with which to perform genetic and drug screening analyses for a better understanding of mucosal melanomas in dogs and humans.

CONCLUSIONS

The aim of this study was to establish and characterize xenograft-derived canine melanoma cell lines with different morphologies, genetic features and pharmacological sensitivities that constitute good predictive models for comparative oncology. These cell lines are relevant tools to advance the use of canine mucosal melanomas as natural models for the benefit of both veterinary and human medicine.

Loss of nuclear BAP1 expression is associated with poor prognosis in oral mucosal melanoma

Oral mucosal melanoma (OMM) is an aggressive neoplasm with an extremely poor prognosis. BAP1 is a tumor suppressor that has been associated with the outcome of melanomas and other malignancies. In this study, we investigated the genetic alterations in BAP1 and the prognostic potential of BAP1 protein expression in oral mucosal melanoma. DNA sequence analysis of BAP1 from 12 OMM patient samples revealed missense mutations in the tissues from four patients. Based on immunohistochemical staining, loss of nuclear BAP1 expression was associated with poor overall survival (P < 0.001, Log-rank = 21.308) and distant metastasis (P = 0.034, OR = 0.320). Multivariate analysis showed BAP1 to be an independent prognostic factor (P = 0.027, HR = 0.479). It thus appears that loss of nuclear BAP1 expression is an independent prognostic factor of poor overall survival and associated with distant metastasis in OMM.

Anorectal mucosal melanoma

Anorectal melanoma is an uncommon and aggressive mucosal melanocytic malignancy. Due to its rarity, the pre-operative diagnosis remains difficult. The first symptoms are non-specific such as anal bleeding, anal mass or pain. Although anorectal melanoma carries a poor prognosis; optimal therapeutics strategies are unclear. Surgical resection remains the mainstay of treatment. The optimal surgical procedure for primary tumours is controversial and can vary from wide local excision or endoscopic mucosal resection (EMR) to an abdomino-perineal resection. A high degree of uncertainly exists regarding the benefit of radiation therapy or chemotherapy. The treatment of advanced melanoma is evolving rapidly with better understanding of the disease biology and immunology. Considerable effort has been devoted to the identification of molecular determinants of response to target therapies and immunotherapy.

Local control in sinonasal malignant melanoma: Comparing conventional to hypofractionated radiotherapy

BACKGROUND

The purpose of this study was to analyze the effect of fractionation schedule on local control in postoperative radiotherapy (RT) for sinonasal malignant melanoma.

METHODS

Sixty-three patients who were treated with surgery and postoperative RT in 4 accredited head and neck cancer centers in the Netherlands between 1998 and 2013 were retrospectively studied. Outcomes with conventional fractionation (2-2.4 Gy per fraction; n = 27) were compared to hypofractionation (4-6 Gy per fraction; n = 36). The primary endpoint was local control and the secondary endpoint was toxicity.

RESULTS

Comparable local control rates were found after 2 and 5 years (63% vs 64% and 47% vs 53%; P = .73 for, respectively, conventional fractionation vs hypofractionation). Local recurrences were predominantly present ipsilateral (92%) and within the irradiated volume (88%). Late toxicity grade ≥ 3 was observed in 2 of 63 patients, 1 patient in both groups.

CONCLUSION

Radiotherapy fractionation schedule did not influence the local control rate or the incidence of late toxicity in patients treated with surgery and RT for sinonasal malignant melanoma in this retrospective analysis. Due to this retrospective nature and the limited number of patients, strong recommendations cannot be made. Expected toxicity, patient convenience, and workload may be taken into account for the choice of fractionation schedule until conclusive evidence becomes available.

Periodic acid-Schiff-positive loops and networks as a prognostic factor in oral mucosal melanoma

The prognostic factors of oral mucosal melanoma (OMM), a rare and aggressive neoplasm, remain to be determined. The aim of this study is to investigate the prognostic significance of vasculogenic mimicry in OMM. The clinical data of 62 patients with primary OMM treated in Shanghai Ninth People's Hospital from April 2007 to April 2012 were retrieved and analyzed retrospectively. Staining of periodic acid-Schiff (PAS) and CD31 immunohistochemistry were performed to evaluate the prognostic value of PAS-positive patterns, blood lakes, and microvascular density. PAS-positive loops and networks (P<0.001) as well as blood lakes (P=0.040) were found to be predictors of overall survival (OS). The presence of PAS-positive loops and networks was an independent prognostic factor of poor OS in multivariate analysis (P=0.002). Although the presence of PAS-positive loops and networks was associated with hematogenous metastasis (P=0.041) and lymphogenous metastasis (P=0.041), it was not an independent predictor of both types of metastasis in multivariate analysis. Microvascular density was not associated with OS (P=0.627) and metastasis of OMM patients. PAS-positive loops and networks have a significant prognostic value in OMM. Detection of PAS-positive patterns may lead to better staging and serve as a prognostic parameter of OMM.

Clinics, prognosis and new therapeutic options in patients with mucosal melanoma: A retrospective analysis of 75 patients

Mucosal melanomas represent a rare entity with different risk factors and molecular features compared to cutaneous melanomas. They arise most commonly from mucosal surfaces in the head/neck region, the female genital tract (FGT) and the anorectal region. The aim of this study was to evaluate clinics, prognosis, and treatment options of patients with mucosal melanoma, in particular with regard to different primary sites.We retrospectively analyzed 75 patients with mucosal melanomas diagnosed in the years 1993 to 2015 in our department. The primary melanomas were located in the head/neck region (n = 32), the FGT (n = 24), and the anorectal region (n = 19).The median age of the patients was 66 years. At initial diagnosis the primary melanoma was not completely resectable in 11 (15%) patients, 18 (24%) patients had regional lymph node metastases, and 7 (9%) patients distant metastases. During follow-up, 22 (29%) patients suffered from a local recurrence, in particular patients with primary melanoma in the head/neck region without postoperative radiotherapy. By multivariate analysis location of the primary melanoma in the head/neck area or anorectal region and presence of metastases at time of diagnosis represented poor prognostic factors for recurrence-free survival. In 62 tested individuals 7 KIT mutations were found, 2 BRAF mutations in 57 tested patients. Four patients received targeted therapies, 14 checkpoint inhibitors, 4 (1/1 on vemurafenib, 1/7 on ipilimumab, and 2/7 on PD-1 inhibitors) patients showed responses of more than 100 days duration.Mucosal melanomas are often locally advanced or metastatic at initial diagnosis, thus they require extensive staging procedures. The high rate of local recurrences in the head/neck region can be significantly reduced by postoperative radiotherapy. For the potential use of medical treatment a mutation analysis for KIT and BRAF genes should be performed. The use of new immunologic and targeted therapies has to be further evaluated.

Prognostic significance of nestin in primary malignant melanoma of the oral cavity

Several studies have examined the correlation between nestin expression and the degree of tumor invasion in cutaneous melanoma. However, no information has been reported on nestin in primary mucosal melanoma of the head and neck. The present study examined the expression and prognostic significance of nestin in patients with primary mucosal melanoma of the oral cavity. Nestin expression was examined immunohistochemically in 39 patients (six oral melanoma in-situ cases and 33 invasive oral melanoma cases) and analyzed for association with disease progression. Age, sex, anatomic site, stage, level of invasion, regional lymph node metastasis, surgical margin involvement, and treatment modality were also analyzed. In the 33 invasive melanoma cases, invasion depth correlated significantly with prognosis in univariate and multivariate analyses. High-intensity nestin staining was observed in 14 of the 33 cases and a high proportion of nestin-positive cells was observed in 16 cases. In stage III oral melanoma cases, nestin expression was not significantly associated with disease progression. However, in stage IV cases, both the intensity and the proportion of nestin expression were significantly associated with disease progression (P=0.022 and 0.005, respectively). In all 33 invasive cases, multivariate analyses showed that both the intensity and the proportion of nestin were significantly associated with a poor prognosis (P=0.014 and 0.009; hazard ratio, 3.59 and 4.05; 95% confidence interval, 1.29-9.98 and 1.42-11.56, respectively). In conclusion, nestin can be a valuable prognostic indicator in the advanced-stage (stage IV) cases of oral mucosal melanoma.

Primary mucosal melanoma of the head and neck in Denmark, 1982-2012: Demographic and clinical aspects. A retrospective DAHANCA study

Background The study was performed to determine the epidemiological, clinical, and histopathological characteristics and prognosis of primary mucosal melanoma of the head and neck (MMHN) in Denmark. Material and methods This was a national retrospective multicenter study of patients diagnosed with MMHN between 1982 and 2012 in Denmark. Data were retrieved from national databases and patient records. Incidence trends were examined for the entire period. We prepared survival curves and performed univariate and multivariate analysis for the period 1992-2012 to identify possible prognostic factors. Results No significant trends in incidence were found in the study period. The three-year overall and disease-free survival rates for MMHN were 46.5% and 35.5%, respectively. Negative margins was an independent predictor of disease-free survival, and age below 65, absence of distant metastases, and low overall TNM stage were predictors of overall survival. Radiotherapy did not improve survival significantly. Recurrence rates were high, even for patients with negative margins. Conclusions MMHN remains a rare disease with a poor prognosis, particularly for patients aged over 65, those with distant metastasis, and those with advanced TNM stage. Importantly, the rate of recurrence is lowest in patients with negative margins.

Graphite Tattoo on the Gingiva: A Case Report

INTRODUCTION

Graphite tattoos may easily be confused with amalgam tattoos and have been reported on infrequently in relevant literature. To the best of the authors' knowledge, this is the first case report in which the incineration method was used for the histopathologic diagnosis of a graphite tattoo on the gingiva.

CASE PRESENTATION

A 24-year-old female patient was referred to the periodontology department of Ankara University, Ankara, Turkey, for evaluation of an asymptomatic pigmented lesion on the maxillary anterior gingiva. A gray-blackish, irregularly shaped macule was observed on the maxillary anterior attached gingiva between the left central and lateral incisors. Radiographs showed no radiopaque foreign particles or pathologic changes in alveolar bone and related teeth. The pigmented area was removed using an excisional incision. The incineration method was used as a differential diagnosis for the histopathologic examination. There was no additional recurrence of the problem by the end of a 1-year follow-up examination.

CONCLUSIONS

The diagnosis of pigmented lesions of the oral cavity and gingiva shows different variations. It is not always possible to distinguish a benign pigmented lesion from an early melanoma on the basis of clinical features alone. A biopsy is usually recommended for focal oral pigmented lesions that cannot be explained by local factors. The incineration method can be used for differential diagnosis between melanin and graphite tattoo accumulation because carbon can be eradicated with this method. However, the same cannot be said for melanin.

Biopanel identifies expression status of targetable proteins in sinonasal melanoma

BACKGROUND

Advanced stage at presentation, lack of BRAF mutations and overall rarity pose unique challenges to the therapy and trial design in sinonasal melanoma.

METHODS

Here, we assessed the expression status of 12 proteins in two independent cohorts of sinonasal melanoma (n = 20).

RESULTS

Each case showed expression of at least one protein (KIT, TP53, MYC, HER2, EGFR, MET, VEGFR, BRAF V600E and/or MDM2), whereas lack of ALK, FLI1 and PDGFRα expression underscores differences to cutaneous melanoma. Comparison of marker frequencies to a metareview of the literature indicates that MYC, HER2, EGFR and MET had not been previously assessed.

CONCLUSION

Expression of at least one potentially targetable protein per case illustrates proteome pathway profiling as one starting point for marker stratified trial design.

Survival Outcomes of Mucosal Melanoma in the Head and Neck: Case Series and Review of Current Treatment Guidelines

PURPOSE

Malignant mucosal melanoma of the head and neck (MMHN) is an aggressive and rare neoplasm with poor long-term outcomes. The aim of this study is to evaluate the outcomes of patients treated by a single-institution head and neck multidisciplinary team.

MATERIALS AND METHODS

In this retrospective case series, all MMHN cases treated at the Royal Melbourne Hospital from 1990-2015 were retrospectively reviewed. Patient demographic characteristics (eg, age), treatment offered, pathology, and outcomes were collected, tabulated, and correlated with outcomes. Survival outcomes were calculated by the Kaplan-Meier method. Comparison was made between oral and sinonasal melanomas.

RESULTS

A total of 16 cases were identified. Two were excluded because of inaccessible data. Of the 14 remaining cases, 8 were sinonasal melanomas and 6 were oral cavity melanomas. Sinonasal tumor patients presented with epistaxis or visual impairment. Oral melanoma patients presented with pigmented lesions or ulceration. Follow-up ranged from 4 months to 11 years. In 2 patients, locoregional recurrences developed that were successfully re-excised. Six patients died of distant metastases despite clear surgical margins. Two patients with sinonasal melanomas died of extensive local disease with intracranial invasion. One patient died 4 years after diagnosis without disease. There were no failures in the neck. The 2- and 5-year overall survival rates were 63.3% and 31.7%, respectively, by the Kaplan-Meier method. The difference in survival between oral and sinonasal melanomas was not statistically significant.

CONCLUSIONS

Despite clear surgical margins, MMHN has a poor prognosis and most deaths are due to distant metastases. Systemic therapies such as those used in cutaneous melanoma treatment might be used in the future for MMHN.

Comparative Aspects of Canine Melanoma

Melanomas are malignant neoplasms originating from melanocytes. They occur in most animal species, but the dog is considered the best animal model for the disease. Melanomas in dogs are most frequently found in the buccal cavity, but the skin, eyes, and digits are other common locations for these neoplasms. The aim of this review is to report etiological, epidemiological, pathological, and molecular aspects of melanomas in dogs. Furthermore, the particular biological behaviors of these tumors in the different body locations are shown. Insights into the therapeutic approaches are described. Surgery, chemotherapy, radiotherapy, immunotherapy, and the outcomes after these treatments are presented. New therapeutic perspectives are also depicted. All efforts are geared toward better characterization and control of malignant melanomas in dogs, for the benefit of these companion animals, and also in an attempt to benefit the treatment of human melanomas.

DNA methylation-induced E-cadherin silencing is correlated with the clinicopathological features of melanoma

E-cadherin, a calcium-dependent cell-cell adhesion molecule, has an important role in epithelial cell function, maintenance of tissue architecture and cancer suppression. Loss of E-cadherin promotes tumor metastatic dissemination and predicts poor prognosis. The present study investigated the clinicopathological significance of E-cadherin expression in cutaneous, mucosal and uveal melanoma related to epigenetic mechanisms that may contribute to E-cadherin silencing. E-cadherin expression was reduced in 55/130 cutaneous (42.3%), 49/82 mucosal (59.7%) and 36/64 uveal (56.2%) melanoma samples as compared to normal skin controls and was inversely associated with promoter methylation. Of the 10 different CpG sites studied (nt 863, 865, 873, 879, 887, 892, 901, 918, 920 and 940), two sites (nt 892 and 940) were 90-100% methylated in all the melanoma specimens examined and the other ones were partially methylated (range, 53-86%). In contrast, the methylation rate of the E-cadherin gene was low in normal tissues (range, 5-24%). In all the three types of melanoma studied, a significant correlation was found between reduced levels of E-cadherin and reduced survival, high mitotic index and metastasis, accounting for the predilection of lymph nodal localization. In cutaneous and mucosal melanoma, low E-cadherin expression was positively correlated also with head/neck localization and ulceration. A high frequency of reduced E-cadherin levels occurred in choroid melanomas. In vitro experiments showed that E-cadherin transcription was restored following 5-aza-2'-deoxycytidine (5-aza-dC) treatment or DNMT1 silencing and was negatively correlated with the invasive potential of melanoma cells. The significant relationship between E-cadherin silencing and several poor prognostic factors indicates that this adhesion molecule may play an important role in melanomagenesis. Therefore, the inverse association of E-cadherin expression with promoter methylation raises the intriguing possibility that reactivation of E-cadherin expression through promoter demethylation may represent a potential therapeutic strategy for the treatment of melanoma.

Cancers of the nose, sinus, and skull base

Malignancies of the nose, sinus, and skull base are rare. The most common histologies are squamous cell carcinoma and adenocarcinoma. The most common primary sites are the nasal cavity and maxillary sinus. Management of these tumors is technically challenging because they often present in advanced stages with extensive disease invading important structures such as the orbit and the skull base. In the last few decades advances in surgical resection techniques, as well as improved strategies to deliver adjuvant radiation, have substantially improved the outcomes in patients with malignancies of the sinonasal tract and skull base.

Evaluation of the prognostic impact of postoperative adjuvant radiotherapy on head and neck mucosal melanoma: a meta-analysis

Background

Head and neck mucosal melanoma (HNMM) is a rare type of malignant tumor that frequently exhibits postoperative recurrence and distant metastasis. Many clinicians administer postoperative adjuvant radiotherapy to improve patient prognosis and enhance quality of life; however, the effects of this treatment remain controversial. Therefore, in this study, a meta-analysis was performed to evaluate the practical value of postoperative adjuvant radiotherapy for head and neck mucosal melanoma.

Methods

Articles in the PubMed, MEDLINE, Cochrane Library, Web of Science and EMBASE databases were systematically retrieved. Analyses were conducted to compare the impact of treatments involving postoperative radiotherapy with treatments entailing surgery alone on patient overall survival time, local recurrence and distant metastasis. The hazard ratio (HR) was used to evaluate the time-to-event data employing RevMan version 5.2 and Stata/SE version 13.0 software according to the principles specified for systematic reviews of interventions in the Cochrane handbook.

Results

Twelve cohort studies involving 1593 patients satisfied the desired conditions. In comparing surgery alone with postoperative radiotherapy, there was no significant difference regarding a decrease in the death risk in HNMM patients (HR, 1.07; 95 % CI, 0.95–1.2; p = 0.903; low heterogeneity, I² = 0); this was also the case for sinonasal melanoma after subgroup meta-analysis (HR, 1.04; 95 % CI, 0.8–1.36; p = 0.983; low heterogeneity, I² = 0 %). A sensitivity analysis and subgroup meta-analysis showed that disease progression was the main source of the instability in the results. Surgery combined with postoperative radiotherapy reduced the risk of local recurrence (HR, 0.51; 95 % CI, 0.35–0.76; p = 0.155) but did not reduce the risk of distant metastasis (HR, 2.26; 95 % CI, 1.01–5.05; p = 0.006).

Conclusions

This study demonstrated that for HNMM patients surgery is recommended if indicated, and surgery combined with postoperative radiotherapy is also recommended for dramatically improved local control of the tumor bed. For patients not suitable for surgical treatment, radiotherapy is still advised. To control distant metastasis and finally lower the risk of death, immunological therapy is another potential option whose therapeutic effect needs to be proved with more data from clinical trials.

Post-treatment Evaluation of Paranasal Sinuses After Treatment of Sinonasal Neoplasms

The aim of imaging in the follow-up of asymptomatic patients treated for sinonasal neoplasms is to detect submucosal relapsing lesions. The challenge is to discriminate recurrent tissue within the changes resulting from unpredictable healing of tissue after surgery and radiotherapy. Scar, inflammation, and recurrence can be better separated with a multisequence MR imaging approach. The choice of the field of view should take into account the risk of in-field intracranial recurrences, craniofacial bone metastases, and perineural spread. Fluorodeoxyglucose-PET has a role in assessing distant metastasis. Its usefulness in local and regional surveillance has yet to be established.

Primary Malignant Melanoma of the Lip: A Report of 48 Cases

PURPOSE

Lip melanoma (LM) is a rare malignant tumor and well-established treatment protocols for it are in short supply. The objective of this study was to evaluate the outcome of treatment modalities and explore the prognostic factors.

PATIENTS AND METHODS

A retrospective chart review was performed on 48 patients with primary LM treated in the authors' hospital from January 1992 to November 2013. The clinical characteristics and treatment modalities were identified and correlated with the outcomes.

RESULTS

The 5-year overall survival (OS) rate was 56.1%, and the rate of cervical lymph node (CLN) metastasis was 46% (22 of 48). A tumor of at least 4 cm (P = .001), nodular types (P = .003), and CLN (P < .0001) were independent prognostic factors for OS. Twenty-five patients died during follow-up, mainly from to neck recurrence (14 of 25). Chemotherapy significantly improved the 5-year OS rate in patients with stage IV LM (P = .03), but not in those with stage III (P = .8).

CONCLUSIONS

LM has a lower CLN and distant metastasis rate and a better prognosis than other oral mucosal melanomas. A long history of melanin pigmentation is a dangerous sign for all patients, and smoking seems to be associated with LM in male patients. Tumor size (≥4 cm), nodular type, and CLN positivity are poor prognostic factors. A wide excision with close observation is advocated as the primary treatment for stage III LM. Adjuvant chemotherapy is useful for patients with stage IV cancer, but not for those with stage III.

Prognostic factors of oral mucosal melanoma: histopathological analysis in a retrospective cohort of 82 cases

AIMS

To investigate the histopathological predictors of overall survival and metastatic failure of oral mucosal melanoma (OMM), of which the histopathological classification and microstaging has not been established.

METHODS AND RESULTS

The pathological data, including cell type (CT), level of invasion, ulceration, mitotic rate, pigmentation, necrosis, tumour-infiltrating lymphocyte (TIL) and vascular invasion, of 82 OMM patients from April 2002 to April 2012 were reviewed and analysed retrospectively. CT, ulceration, mitotic rate, pigmentation, necrosis and vascular invasion were found to be of significance in predicting the overall survival of OMM patients. CT was an independent prognostic factor of overall survival in multivariate analysis. In patients with localized OMM, CT, level of invasion, mitotic rate, pigmentation and necrosis were associated with overall survival but none of them proved to be an independent prognostic factor. CT, mitotic rate and TIL were associated with the risk of distant metastasis. TIL was revealed to be an independent factor of distant metastases risk in multivariate analysis.

CONCLUSIONS

CT was an independent prognostic factor of overall survival. Patients with epithelioid cell type OMM had a poor prognosis. Patients without TIL had a higher risk of distant metastasis.

PTEN Methylation Dependent Sinonasal Mucosal Melanoma

Sinonasal mucosal melanoma (SMM) is an aggressive and rare type of melanoma. Although the classic RAS-RAF-MEK pathway is thought to be the main pathway involved in melanoma pathogenesis, genetic alterations in the phosphatidylinositol 3-kinase-AKT pathway, including PTEN-regulated signaling, are also thought to contribute. So far, data regarding altered PTEN expression and epigenetic mechanism of PTEN silencing in development of SMM is extremely limited. Herein we report on a case of SMM with liver and bone metastases with an epigenetic alteration of PTEN. Results of mutation analysis for BRAF, NRAS, HRAS, KRAS, PIK3CA, c-Kit, and PTEN were negative; however, methylation of PTEN CpG islands was observed. Our case not only supports PTEN as a major tumor suppressor involved in melanoma tumorigenesis, but also a potential epigenetic mechanism of PTEN silencing in development of SMM.

Cisplatin fails to induce puma mediated apoptosis in mucosal melanomas

OBJECTIVES

Mucosal melanomas (MM) are aggressive subtypes of common melanomas. It remains unclear whether limitations in their resectability or their distinctive molecular mechanisms are responsible for the aggressive phenotype.

METHODS

In total, 112 patients with cutaneous melanomas (CM) and 27 patients with MM were included. Clinical parameters were analysed using Chi square, Fisher exact and student's t-test. Survival rates were calculated by Kaplan-Meier. Analysis of p53, p21, Mdm2, Hipk2, Gadd45, Puma, Bax, Casp9 and Cdk1 via quantitative PCR and immunohistochemistry (IHC) was performed. TP53 induction after cisplatin treatment was analysed in 10 cell lines (melanocytes, four MM and five CM) using western blot (WB) and qPCR.

RESULTS

The overall/recurrence-free survival differed significantly between MM (40 months and 30 months) and CM (90 months and 107 months; p < 0.001). IHC and WB confirmed high p53 expression in all melanomas. Hipk2 and Gadd45 showed significantly higher expressions in CM (p < 0.005; p = 0.004). QPCR and WB of wild-type cell lines demonstrated no differences for p53, p21, Mdm2, Bax and Casp9. WB failed to detect Puma in MM, while Cdk1 regulation occurred exclusively in MM.

CONCLUSIONS

The aggressive phenotype of MM did not appear to be due to differential expressions of p53, p21, Mdm2, Bax or Casp9. A non-functional apoptosis in MM may have further clinical implications.

Impact of different surgical and postoperative adjuvant treatment modalities on survival of sinonasal malignant melanoma

Background

The role of postoperative adjuvant treatment for sinonasal malignant melanoma remains unclear. This study evaluates the impact of three different surgical and postoperative adjuvant treatment modalities: surgery alone(open and endoscopic approaches), surgery plus radiotherapy and surgery, radiotherapy plus chemotherapy on survival of patients with primary sinonasal malignant melanoma (SMM).

Methods

The data of 69 patients who underwent primary surgical treatments at Eye & ENT hospital of Fudan University between January 1st, 2000 and December 31st, 2010 were retrospectively reviewed. Survival comparison of different surgical and postoperative adjuvant treatment modalities (surgery alone, surgery plus radiotherapy and surgery, radiotherapy plus chemotherapy), as well as survival comparison between open and endoscopic surgical approaches were performed. Curves depicting survival were performed using Kaplan-Meier method. Statistical analysis was performed using log-rank test software SPSS19 and p < .05 is considered as statistically significant.

Results

The median overall survival time was found to be 18 months for surgery alone (27 cases), 32 months for surgery plus radiotherapy (24 cases), 42 months for surgery, radiotherapy plus chemotherapy (18 cases). The 3 and 5 year survival rates for groups mentioned above were 14.8% and 5.6%, 45.1% and 31.6%, 55% and 32.1%, respectively. Statistical significances were found not only between surgery alone and surgery plus radiotherapy treatment group (P = 0.012), but also surgery alone and surgery, radiotherapy plus chemotherapy group (P = 0.002). There was no statistically significant survival difference found between the two different surgical approaches (41 cases for open approach and 28 cases for endoscopic approach).

Conclusions

Sinonasal malignant melanoma is a disease with a poor prognosis. Patients who underwent surgery plus radiotherapy or surgery, radiotherapy plus chemotherapy had better survival outcomes than those underwent surgery alone. Endoscopic approach provided similar survival outcome as an open approach.

Fast neutron radiotherapy for primary mucosal melanomas of the head and neck

BACKGROUND

Primary head and neck mucosal melanomas (HNMMs) are rare tumors managed with surgery and/or radiotherapy and associated with poor outcomes. Given their radioresistance, high linear energy transfer radiotherapy with neutrons may improve local control.

METHODS

We conducted a retrospective review of 14 patients with HNMM treated with neutrons at the University of Washington from 1990 to 2012. Five patients had T3 disease, 9 had T4 disease, 3 had regional nodal disease, and 4 had distant metastases at diagnosis. Primary sites were sinonasal (n=10), lip (n=2), and palate (n=2). Ten patients had initial surgical resection/debulking.

RESULTS

Nine patients had gross residual disease, 6 had complete response, and 3 had partial response. Local control was achieved in 79% until death or last follow-up, and 50% developed distant metastases. Kaplan-Meier 5-year local control was 66% and overall survival was 21%.

CONCLUSION

High rates of locoregional control were achieved with neutrons, despite the presence of gross disease. Survival was limited by early distant metastases.

The role of radiotherapy in the management of sinonasal melanoma and its impact on patients and healthcare professionals

The aim of this paper is discuss the contemporary issues surrounding radiotherapy for sinonasal mucosal melanoma (SNMM). SNMM is a rare disease with a poor prognosis. The particular challenge with regard to radiotherapy for SNMM is that melanoma is a relatively radioresistant tumour in an anatomical site surrounded by important radiosensitive structures. IMRT has been shown to be an effective primary and adjuvant therapy, and is superior to traditional photon radiotherapy techniques. Emerging evidence also supports the role of particle therapy. Protons and carbon ions may provide a superior target dose and less collateral damage than IMRT. Stereotactic radiotherapy has also been used successfully. The introduction of new technology will always be inhibited by financial constraints and concerns about long-term efficacy. The role of the health professional will change commensurate with the introduction of new technology in terms of the knowledge and the clinical skills they must acquire. Working patterns may need to change to manage the competing interests of expanding services and financial cutbacks. In addition to the clinical expertise health professionals provide, they will be charged with the responsibility of finding innovative ways to improve and develop radiotherapy services for SNMM.

Intraoral Spitz nevus: case report and literature review

Spitz nevi account for approximately 1% of all melanocytic nevi of the skin in children. Although Spitz nevi often develop in the skin of the head and neck, intraoral Spitz nevi are rare. These nevi contain epithelioid and spindle cells and exhibit cytologic and architectural atypia when compared with routine melanocytic nevi, and may be mistaken for atypical Spitz tumor, Spitzoid melanoma, or conventional melanoma. Here, we report a Spitz nevus on the buccal mucosa of an 11-year-old boy. The tumor was composed of a proliferation of mostly epithelioid melanocytes with a smaller spindle cell component. The melanocytes were positive for S100, MART-1, and p16 proteins, with HMB-45-positive cells located only in the basal cell layer and superficial lamina propria. Less than 5% of the nuclei were positive for MIB-1, and there were no mitotic figures. We review the literature on 7 previously reported cases of Spitz nevi.

Treatment and prognosis in sinonasal mucosal melanoma: A retrospective analysis of 65 patients from a single cancer center

BACKGROUND

The purpose of this study was to evaluate the outcome in sinonasal mucosal melanoma (SMM).

METHODS

A retrospective analysis of clinicopathological data from January 1976 to December 2005 was performed. Survival curve, univariate, and multivariate analyses were undertaken.

RESULTS

Sixty-eight patients with SMM were enrolled; 3 patients refused treatment. The 3-year and 5-year overall survival (OS) rates in the remaining 65 cases of SMM were 36.5% and 29.7%, respectively. Patients who underwent surgery had better 3-year and 5-year OS rates than those treated without surgery (40.7% and 34.1% vs 21.4% and 14.3%, respectively), and the same was true for patients treated with and without biotherapy (58.2% and 50.9% vs 30.0% and 23.4%, respectively). Distant metastasis at presentation was associated with a worse prognosis. Those patients managed with multimodality treatment had better OS rates.

CONCLUSION

The prognosis in SMM is poor, particularly for those with distant metastasis or without surgery. Multimodality treatment may improve survival.

A rare case of rynopharyngeal melanoma

Primary mucosal melanomas (MM) of the head and neck region constitute 0.5-2% of all malignant melanomas. The rynopharynx is a region that is less often involved by malignant melanomas. Because most of mucosal melanotic lesions are painless in their early stages, the diagnosis is unfortunately often delayed until symptoms resulting from ulceration, growth, and/or bleeding are noted. Here, we document the rare case of a malignant rynopharynx melanoma of a 43 year old woman. Its treatment and the pertinent literature are discussed. No complication was recorded in the post-operative period and no further surgery was performed. The follow up showed no recurrence in the same position and with the same characteristics, even after six years. Mucosal melanomas are aggressive tumours and the prognosis in these patients is poor. Clinicians must use treatment strategies that provide functional benefit, so as to maintain quality of life without excessive toxicity.

Follow-up strategies in head and neck cancer other than upper aerodigestive tract squamous cell carcinoma

Post-therapy follow-up for patients with head and neck cancer other than upper aerodigestive tract squamous cell carcinoma should meet several objectives: to detect both local, regional or distant recurrences, to evaluate acute and long-term treatment-related side effects, to guide the rehabilitation process, and to provide psychosocial support when needed. To our knowledge, there are no published reports in the literature dedicated to the follow-up of patients with these tumours. A comprehensive literature search for post-treatment follow-up strategies spanning from 1980 to 2012 was performed on several databases. This review focuses on malignant salivary gland tumors, soft tissue sarcomas, cutaneous squamous cell carcinomas, and sinonasal adenocarcinomas. Given the varying biological behavior and treatment-related factors and based on the literature, different recommendations are made on the follow-up of patients with the above-mentioned tumors.

Mucosal melanoma in the head and neck region: different clinical features and same outcome to cutaneous melanoma

Mucosal melanoma (MM) in the head and neck (H&N) is relatively rare and behaves in distinct pattern from cutaneous melanoma (CM). We performed this study to define clinical characteristics and outcomes of patients and emphasize MM differences from CM. Forty-one patients with MM located in H&N were assessed. 94 CM patients originated from H&N region were also used for comparison. Patients had oral cavity (51%) and sinonasal location (49%).The median age was 60 years and gender distribution was equal. Thirty-two (78%) patients had localized stage, four (10%) patients had regional lymph node metastasis, and five (12%) patients had distant metastasis. The 1- and 5-year overall survival rates were 81% and 58%, respectively. Outcomes were similar between sinonasal and oral cavity patients (P = 0.67). Advanced disease was the significant prognostic factor for outcome (P = 0.03). MM patients are older (P = 0.008) and more diagnosed as a localized disease patients at presentation than those with CM (P = 0.06). Overall survival rates were identical in patients with MM and CM (P = 0.53). In conclusion, despite different clinical features, outcome was identical in patients with MM and CM located in the H&N region.

Amalgam tattoo mimicking mucosal melanoma: a diagnostic dilemma revisited

Mucosal melanoma of the oral cavity is a rare but highly aggressive neoplasm. However, the clinicians need to be aware of the other and more frequent etiologies of intraoral pigmentation, such as amalgam tattoos. As amalgam has been extensively used for dental restorations and can cause pigmentations in the oral mucosa, this is a differential diagnosis not to be forgotten. We describe the characteristics of these two phenomena and present a case vignette illustrating the differential diagnostic issues. Other causes of intraoral pigmentation are summarized.