Primary oral mucosal melanoma: a series of 35 new cases from South America

Malignant Melanoma of the Oral Cavity: An Aggressive and Rare Entity

It is exceptionally unusual to see oral malignant melanoma, which is highly aggressive with dismal prognosis. A 61-year-old female patient presented with hyperpigmented and hemorrhagic areas in the anterior mandible. Microscopically, positive Immunohistochemistry staining with monoclonal antibody Human Melanoma Black (HMB45) and S100 protein, confirmed the diagnosis as malignant melanoma.

Primary oral and sinonasal mucosal melanomas in Latin America: a systematic review

Primary oral and sinonasal mucosal melanomas (POSNMMs) are aggressive neoplasms with limited therapeutic alternatives. The aim of this review was to characterize the demographic, clinical, immunohistochemical, and molecular information regarding these tumors in the Latin American population. Articles published in English, Spanish, or Portuguese (1990-2022) retrieved from the PubMed/MEDLINE, Scopus, CAS, Web of Science, EBSCO, and Google Academic databases were included. Thirty-three studies, with a total of 1212 cases, were identified. Clinicopathological data were available for 870 cases and immunohistochemical and/or molecular information for 342. Nineteen studies (57.6%) reported cases of oral melanoma, three (9.1%) sinonasal melanoma, and 11 (33.3%) oral and sinonasal melanoma. Fifteen studies (45.5%) provided only clinicopathological data, 12 (36.4%) reported only immunohistochemical data, two (6.1%) shared clinicopathological and immunohistochemical data, one (3.0%) offered clinicopathological, immunohistochemical, and molecular data, one (3.0%) provided immunohistochemical and molecular data, one (3.0%) clinicopathological and molecular data, and one (3.0%) only molecular data. The mean age of individuals with POSNMMs was 58 years, and slightly more were male (male 51.3%, female 48.7%). In Latin America, POSNMMs are a rare but aggressive malignancy with a poor prognosis and limited treatment options. Although molecular data and targeted therapy are still being researched, data from Latin America indicate the need for multicenter collaborative clinical trials to unite individual and isolated efforts.

Oral mucosal melanoma - A systematic review

Oral mucosal melanoma (OMM) is the subject of few studies, resulting in a lack of understanding. The aim of this study is to review the current literature on OMM. The term searched was "oral mucosal melanoma" between 01/01/2000 and 03/15/2021 in the PubMed Database (MEDLINE). Patients presenting with OMM and treated in our center between January 2009 and January 2020 were included in a case series. Demographics, location, risk factors, genetic mutations, treatment performed, and overall survival (OS) rates were evaluated. The PubMed database search yielded a total of 513 results, thirty-eight articles were finally included, which amounted to 2230 cases of OMM. 13 patients were included in the case series. A male-to-female ratio of 1.28:1.00 was found with a mean age at first diagnosis of 58.2 years old. Hard palate (1060 cases) and then gingiva (794 cases) were the two main locations. No risk factors could be identified. OMM were staged III or IV at diagnosis. Mutations were described as such: KIT in 14.6% of cases, BRAF in 7%, and NRAS in 5.6%. Treatment protocols varied but radical surgery was the cornerstone treatment associated with adjuvant therapies. Immunotherapy has not been evaluated for OMM. OS rates were 43.4% at 3 years, 33.1% at 5 year and 15.4% at 10 years. OMM show distinct features from cutaneous melanoma (CM): typical locations, no identified risk factors, different mutations profile, worse prognosis with advanced stage at diagnosis. Targeted therapies are still underused compared to CM.

Toripalimab (anti-PD-1) versus High-Dose Interferon-α2b as Adjuvant Therapy in Resected Mucosal Melanoma: A Phase II Randomized Trial

BACKGROUND

No standard of care for mucosal melanoma (MM) in the adjuvant setting has been established. Meanwhile, relapse-free survival (RFS) is only about five months after surgery alone. This phase II trial aimed to compare toripalimab vs. high-dose interferon-α2b (HDI) as an adjuvant therapy for resected MM.

PATIENTS AND METHODS

From July 2017 to May 2019, 145 patients with resected MM were randomized (1:1) to receive HDI (N = 72) or toripalimab (N = 73) for one year until disease relapse/distant metastasis, unacceptable toxicity, or withdrawal of consent. The primary endpoint was RFS. The secondary endpoints included distant metastasis-free survival (DMFS), overall survival (OS), and safety.

RESULTS

After a median follow-up of 26.3 months, the numbers of RFS, OS, and DMFS events were 51 vs. 46, 33 vs. 29, and 49 vs. 44 in the toripalimab arm and the HDI arm, respectively. The median RFS were 13.6 (95%CI: 8.31-19.02) months and 13.9 (95%CI: 8.28-19.61) months in the toripalimab arm and HDI arm, respectively. The DMFS was not significantly different between the two arms (HR: 1.00, 95%CI: 0.65-1.54). The median OS was 35.1 months (95%CI: 27.93-NR) in the toripalimab arm, with no significant difference in all-cause death (HR: 1.11, 95% CI: 0.66-1.84) for the two arms. The median sums of the patients' actual infusion doses were 3672 mg and 1054.5 MIU in the toripalimab arm and HDI arm, respectively. The incidence of treatment-emergent adverse events with a grade ≥ 3 was much higher in the HDI arm than in the toripalimab arm (87.5% vs. 27.4%).

CONCLUSION

Toripalimab showed a similar RFS and a more favorable safety profile than HDI, both better than historical data, suggesting that toripalimab might be the better treatment option. However, additional translational studies and better treatment regimens are still warranted to improve the clinical outcome of MM.

The Role of Reflectance Confocal Microscopy in the Evaluation of Pigmented Oral Lesions and Their Relationship With Histopathological Aspects

ABSTRACT

Oral pigmentations are a heterogeneous group and can be the result of physiological activity of oral mucosal melanocytes, secondary to exogenous causes, associated with systemic or local diseases, or due to proliferative activity of melanocytes. Their diagnosis is critical because these lesions can be markers of internal diseases or, in the case of melanocytic proliferative processes, they may represent a malignant neoplasm. In the past decade, the use of reflectance confocal microscopy, a noninvasive imaging tool, has aided the analysis of such lesions, but the establishment of firm criteria in their evaluation is still lacking. This study evaluated a series of 19 cases of pigmented oral lesions and correlated the reflectance confocal microscopy findings with histopathological classical criteria. We found 13 cases of melanotic macule, 1 of them associated with Peutz-Jeghers syndrome and 2 with Laugier-Hunzinker syndrome; 1 melanocytic nevus; 2 lentigo maligna; 2 pigmented actinic cheilitis; and 1 case of postinflammatory pigmentation secondary to a lupus erythematosus oral discoid lesion. The main difference between benign and malignant lesions was the presence of atypical proliferation in lentigo maligna. Langerhans cells with thick dendritic processes, which may be present in other benign and inflammatory pigmentations is one of the main reasons for diagnostic pitfalls.

Actionable Mutation Profile of Sun-Protected Melanomas in South America

ABSTRACT

Melanomas that arise in sun-protected sites, including acral and oral mucosal melanomas, are likely under the control of unique, specific mechanisms that lead to mutagenesis through various pathways. In this study, we examined somatic mutations in tumors by targeted sequencing using a custom Ion Ampliseq Panel, comprising hotspots of 14 genes that are frequently mutated in solid tumors. Tumor DNA was extracted from 9 formalin fixation, paraffin-embedded sun-protected melanomas (4 primary oral mucosal melanomas and 5 acral lentiginous melanomas), and we identified mutations in the NRAS, PIK3CA, EGFR, HRAS, ERBB2, and ROS1 genes. This study reveals new actionable mutations that are potential targets in the treatment of photo-protected melanomas. Additional studies on more of these melanoma subtypes could confirm our findings and identify new mutations.

Prognostic Value of an Immunohistochemical Signature in Patients With Head and Neck Mucosal Melanoma

Purpose

We aimed to develop a prognostic immunohistochemistry (IHC) signature for patients with head and neck mucosal melanoma (MMHN).

Methods

In total, 190 patients with nonmetastatic MMHN with complete clinical and pathological data before treatment were included in our retrospective study.

Results

We extracted five IHC markers associated with overall survival (OS) and then constructed a signature in the training set (n=116) with the least absolute shrinkage and selection operator (LASSO) regression model. The validation set (n=74) was further built to confirm the prognostic significance of this classifier. We then divided patients into high- and low-risk groups according to the IHC score. In the training set, the 5-year OS rate was 22.0% (95% confidence interval [CI]: 11.2%- 43.2%) for the high-risk group and 54.1% (95% CI: 41.8%-69.9%) for the low-risk group (P<0.001), and in the validation set, the 5-year OS rate was 38.1% (95% CI: 17.9%-81.1%) for the high-risk group and 43.1% (95% CI: 30.0%-61.9%) for the low-risk group (P=0.26). Multivariable analysis revealed that IHC score, T stage, and primary tumor site were independent variables for predicting OS (all P<0.05). We developed a nomogram incorporating clinicopathological risk factors (primary site and T stage) and the IHC score to predict 3-, 5-, and 10-year OS.

Conclusions

A nomogram was generated and confirmed to be of clinical value. Our IHC classifier integrating five IHC markers could help clinicians make decisions and determine optimal treatments for patients with MMHN.

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.

Distant metastasis from oral cavity-correlation between histopathology results and primary site

OBJECTIVES

Oral cancer is the eighth most common type of cancer worldwide and a significant contributor to the global burden caused by this disease. The principal parameters considered to influence prognosis, and thus treatment selection, are size and location of the primary tumor, as well as assessment of the presence and extent of lymph node and distant metastasis (DM). However, no known report regarding the relationship between the primary site and DM has been presented. For effective treatment selection and good prognosis, the correlation of DM with anatomic site and histopathology results of the primary malignancy is important. In the present study, we performed a systematic review of published reports in an effort to determine the relationship between the anatomic site of various types of oral cavity cancer and DM.

METHODS

A systematic review of articles published until the end of 2018 was performed using PubMed/MEDLINE.

RESULTS

A total of 150 studies were selected for this review. The percentage of all cases reported with DM was 6.3%, ranging from 0.6% to 33.1% in the individual studies. The rate of incidence of tongue occurrence was 9.3%. A frequent DM site was the lungs, with adenoid cystic carcinoma the most commonly involved histopathological factor. Malignant melanoma was most frequent (43.4%) in all histopathology findings, whereas there were no cases with an acinic cell carcinoma or cystadenocarcinoma.

CONCLUSIONS

We found that the occurrence of DM from the primary site as well as rate of incidence was dependent on histopathological factors.

Oral melanomas in HIV-positive patients: Report of two cases and review of the literature

Oral melanoma in HIV-positive patients is exceedingly rare, with only two cases reported in the literature published in English. Herein, we report two additional cases of oral melanomas which occurred as oral masses in the upper gingiva and hard palate in 35- and 27-year-old HIV-positive women. Significant thrombocytopenia, anemia, reduced CD4 cells, and high HIV load occurred in both patients. Microscopically, the lesions showed a variable proliferation of fusiform and epithelioid-pigmented cells, with cellular pleomorphism and high mitotic index. The diagnosis of melanoma was supported by positive immunoreactivity for S-100, MelanA, and HMB-45. Both cases had an unfavorable outcome, and the patients died a few months after the initial diagnosis. Because of its rarity, oral melanoma occurring in HIV-positive patients can pose problems in diagnosis and should be clinically distinguished from Kaposi's sarcoma, which is more common in the context of the immunodeficiency syndrome.

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.

Phosphorylated Akt1 expression is associated with poor prognosis in cutaneous, oral and sinonasal melanomas

Melanomas are highly aggressive tumours derived from melanocytes, which occur most commonly in the skin. Occasionally, these tumours may appear in oral and sinonasal mucous membranes. In this study, we performed a comparative analysis of the Phosphorylated Akt1 (p-Akt1) expression in 144 patients affected by cutaneous (CM), 34 oral cavity (OM), and 31 sinonasal melanomas (SNM). Similar to the metastatic cutaneous melanomas, p-Akt1 was overexpressed in 17/34 of the oral cavity and 20/31 of the sinonasal melanomas. In addition, the p-Akt1-nuclear expression was associated with poorer cancer-specific survival in cutaneous (P < .0001), oral (P < .0001), and sinonasal (P = .001) melanomas. Multivariate analysis showed p-Akt1 to be an independent prognostic marker in oral (P = .041) and sinonasal (P < .0001) melanomas patients. In conclusion, p-Akt1 overexpression is an independent prognostic marker in mucosal melanomas and is significantly up-regulated in sinonasal melanomas. As both mucosal and metastatic cutaneous melanomas showed high frequency of p-Akt1 expression, these findings suggest that mucosal melanomas have a biological behaviour, similar to the aggressive cutaneous melanomas.

Efficacy and safety of primary surgery with postoperative radiotherapy in head and neck mucosal melanoma: a single-arm Phase II study

Background

There still remains no well-established treatment strategy for head and neck mucosal melanoma (HNMM). We aim to evaluate the effectiveness and safety of primary surgery with postoperative radiotherapy for this disease.

Patients and methods

A single-arm, Phase II clinical trial was conducted at Sun Yat-Sen University Cancer Center. Patients with nonmetastatic, histologically proven HNMM were prospectively enrolled. Patients received primary surgery followed by intensity-modulated radiotherapy with an equivalent dose at 2 Gy per fraction of 65–70 Gy to CTV1 (high-risk regions including tumor bed) and 50–55 Gy to CTV2 (low-risk regions). Additional use of adjuvant chemotherapy (AC) depended on consultation from a multidisciplinary team. This trial is registered with ClinicalTrials.gov, number NCT03138642.

Results

A total of 33 patients were enrolled and analyzed between July 2010 and November 2016. There were 18 (54.5%) patients with T3 disease and 15 (45.5%) patients with T4a disease. The median age at diagnosis was 58 years (range 27–83 years), and 61% of the cohort were males. The overall median follow-up duration was 25.3 months (range 5.3–67.1 months). The 3-year overall survival (OS), local relapse-free survival (LRFS), regional relapse-free survival (RRFS), and distant metastasis-free survival (DMFS) rates were 44.4, 91.7, 78.1, and 41.7%, respectively. Patients with T4a disease showed significantly inferior OS (P=0.049) and DMFS (P=0.040) than those with T3 disease. Prophylactic neck radiation (PNR) was nearly associated with superior RRFS (P=0.078). However, there was no significant difference in OS, LRFS, RRFS, and DMFS for patients treated with or without AC (P>0.05 for all). Toxicities were generally mild to moderate.

Conclusion

Primary surgery with postoperative radiotherapy yielded excellent local control and acceptable toxicity profile for HNMM. Nevertheless, high rates of distant metastases resulted in limited survival.

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.

Prognostic factors in head and neck mucosal malignant melanoma

OBJECTIVE

Primary mucosal malignant melanoma of the head and neck (HN-PMMM) is an aggressive and uncommon neoplasm. Herein, we present a series of 33 patients and the results of treatment, and aimed to determine prognostic factors in HN-PMMM.

METHODS

Patients who were diagnosed as having HN-PMMM in our reference hospital, between 2005 and 2014 were evaluated. Thirty-three of these patients who had follow-up data were included. Surgical margin status was extracted from the original pathology reports. Archived materials were retrieved for the histopathologic findings: ulceration, necrosis, lymphovascular invasion, perineural invasion, pigmentation, and presence of an in situ component. Mitotic activity was evaluated using phosphohistone H3 (PHH3) immunohistochemical staining.

RESULTS

We found an association of PHH3 mitotic activity with overall survival in a univariate analysis and to our knowledge, this is the first report among the available case series of HN-PMMM to evaluate mitotic activity using immunohistochemical staining. We also investigated the relationship between multicentricity and locoregional recurrence, which the authors believe is also a first.

CONCLUSION

PHH3 mitotic activity can be used a prognostic factor for head and neck mucosal malignant melanoma.

Update from the 4th Edition of the World Health Organization Classification of Head and Neck Tumours: Mucosal Melanomas

The updated edition of The World Health Organization Classification of Tumours of the Head and Neck includes discussions on mucosal melanoma of both the sinonasal and oral cavity. Since the prior edition, sinonasal origin is now recognized as the most common site of occurrence of mucosal melanoma in the head and neck (66%) with oral cavity representing 25% of cases. Histologic features of mucosal melanomas vary widely from spindled, epithelioid, and pleomorphic to rhabdoid, plasmacytoid and undifferentiated. Additionally, mucosal melanomas are commonly amelanotic (or minimal pigmentation) (~50%) leading to overlapping features and diagnostic challenges in differentiating mucosal melanomas from other small cell/undifferentiated sinonasal tumors. Since the last edition, formal staging of head and neck mucosal melanomas was added to the American Joint Committee on Cancer entities, though the traditional histologic features that have prognostic significance in cutaneous melanomas fail to stratify mucosal melanomas (i.e. tumor thickness, ulceration). Interestingly, while melanomas of all sites are a malignancy derived from melanocytes, mucosal melanomas are now recognized to have distinct molecular alterations compared to cutaneous or uveal melanomas. BRAF V600E mutations are rare (<6%) in mucosally derived melanomas compared to a rate of 50% in cutaneous melanomas. CD117 (C-Kit) mutations are the most common alteration encountered (~25%) in mucosal sites with potential therapeutic targetability. The recognition of the distinct genetic changes in this subgroup of melanomas means that therapy advances in cutaneous melanomas may not translate to head and neck mucosal melanomas and clinical trials specific to this subgroup of patients are needed.

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.

Optimal multidisciplinary treatment of oral cavity mucosal melanoma: outcome analysis in a case series

Oral cavity mucosal melanomas (OCMM) represent only 3% of all malignant melanomas. Surgery is the mainstay of treatments and it is often followed by adjuvant radiotherapy. The role of adjuvant immunotherapy and/or chemotherapy is still debated and to date neither treatment is routinely used. From January 1990 to January 2010, we have collected from our database data of 20 patients with a histologically proven diagnosis of OCMM. Upfront surgery, followed by adjuvant radiotherapy was performed in 16/20 (80%) patients. Immunohistochemical analysis was carried out on all tissue samples and the following markers were assessed: Ki-67, HMG-45, Melan-A, S-100, CD31, CD35, CD20, CD21, and CD3. Although Ki-67, HMG-45, Melan-A, and S-100 were assessed in tumor cells, the analysis of CD31, CD21, CD20, CD3, and CD35 was carried out on the tumor-infiltrating lymphocytes. Patient outcome was analyzed and associated with clinical and Immunohistochemical tumor characteristics. The median overall survival (OS) was 12 months, with a 2-year OS rate of 30%. The median progression-free survival (PFS) was 9 months, with a 2-year PFS rate of 25%. Grade of lymphocyte infiltration (CD20 and CD3 expression) correlated strongly with prognosis. Interestingly, overexpression of CD21 along with downregulation of CD31 was significantly associated with better OS and PFS, whereas the reversal features correlated with a poor prognosis. Our report shows that patients affected by OCMM have a poor prognosis despite the administration of multimodal treatments. Moreover, our analysis suggests that the evaluation of several biomarkers, especially in tumor-infiltrating lymphocytes, may identify categories of patients with distinct immune response against the tumor and possibly different treatment response and prognosis.

Oral Malignant Melanoma Initially Misdiagnosed as a Racial Pigmentation: A Case Report

Oral malignant melanoma (OMM) is rare, representing less than 0.5% of all oral malignancies. The most affected sites are the palate and the maxillary gingiva. Histological examination is important to establish the diagnosis of any suspicious pigmented lesion in the oral cavity, mainly if a precise clinical diagnosis is not possible. We present one case of OMM that was initially diagnosed as a racial pigmentation elsewhere 2 years earlier. Clinical examination showed multiple macules and nodules located on the hard and soft palate, gingiva and superior alveolar mucosa. These lesions were painless and presented a color variation going from dark blue to black. Histological analysis showed sheets and nests of atypical melanocytes displaying a range of shapes such as plasmacytoid, epithelioid, and round cells, located in the superficial corium extending to the deep tissues. A few tumor cells contained variable amounts of melanin. There was no invasion of blood vessels or nerve fibers. Immunohistochemical analysis revealed that the neoplastic cells were positive for HMB-45, melan-A, S-100 and negative for AE1/AE3, confirming the diagnosis of melanoma. The Ki-67 labeling index was around 25%. The patient refused any treatment and died 11 months later.

The management and site-specific prognostic factors of primary oral mucosal malignant melanoma

Primary oral mucosal malignant melanoma (POMM) is uncommon. Its biological behavior is more aggressive than that of cutaneous malignant melanoma. Its site-specific prognostic factors and optimal management have not been determined yet. Retrospective POMM case analysis from peer-reviewed publications in the PubMed and Embase electronic database from January 1984 to December 2013, in which therapy and outcome data were available, was performed. A total of 151 primary cases were extracted from 39 peer-reviewed English literatures. The study population includes 63 males and 88 females with a medium age of 61 years. The treatment protocols include surgery alone (18%), radiotherapy alone (14%), surgery plus radiotherapy (14%), surgery plus chemotherapy (31%), as well as surgery plus chemoradiotherapy (15%) and chemoradiotherapy (8%). The male patients have a higher risk for metastasis than the female patients do (odds ratio [OR]; 3.41, P = 0.021). The POMM originating from specialized mucosa was associated with increased risk for tumor recurrence and mortality (OR, 4.03, P = 0.001; OR, 2.03, P = 0.031, respectively). The patients who had surgery-based multiple therapy have a significantly longer survival compared with those who had surgery alone and those who had no surgical treatment (P = 0.000). The age of 60 years or younger (hazard ratio [HR], 4.69; P = 0.000), nonsurgical treatment (HR, 12.838; P = 0.000), and surgery alone (HR, 1.517; P = 0.001) were independent adverse prognostic factors for overall survival. Taken together, the study results suggest that surgery-based multiple therapy is the most effective treatment protocol. The age of 60 years, nonsurgical treatment, and surgery alone were independent adverse prognostic factors for overall survival.

Primary malignant mucosal melanoma of the upper lip: a case report and review of the literature

Background

Malignant melanoma of oral cavity is a rare condition, accounting for 0.5 % of all oral malignancies and about 1–2 % of all melanomas. Oral melanomas have extremely poor prognosis with 5 years survival rate of 12.3 %. The poor prognosis compared to cutaneous melanoma may be attributed to delay in reporting by patient and diagnosis, and apt to become ulcerated due to repeated trauma. The ‘chameleonic’ presentation of a mainly asymptomatic condition, the rarity of these lesions, the poor prognosis and the necessity of a highly specialized treatment are factors that should be seriously considered by the involved health provider.

Case presentation

We present a case of 32 years old male of Han ethnicity with mucosal melanoma of upper lip, comparing his clinical presentation and histological findings at his first visit and following the recurrence. The patient complained of black discoloration on the left side of upper lip since 4 years which gradually increased in size and later involved the skin of the lip. Excision with 5 mm safety margin was performed but the patient presented with the similar lesion after three and half years of the treatment. So, again wide excision with 2 cm safety margin was performed followed by reconstruction of the lip.

Conclusion

This case provides an example of aggressive behavior of mucosal melanoma and emphasizes on the fact that any pigmented lesion detected in the oral cavity may exhibit potential growth and should be submitted to biopsy to exclude malignancy. It also exemplifies of how the time of diagnosis and the evolution of a disease could be seriously influenced by patient’s behavior.

Mucosal melanoma of the head and neck: recurrence characteristics and survival outcomes

OBJECTIVE

The aim of this study was to review oncologic outcomes and recurrence characteristics of head and neck mucosal melanomas (HNMMs) managed at a tertiary referral center.

STUDY DESIGN

Clinical records of 10 patients who were managed for HNMMs between 2001 and 2013 were retrospectively analyzed.

RESULTS

The median age was 66 years (range 28-76 years) and male/female (M/F) ratio was 1:5. The 3-year disease-free survival (DFS) rates and overall survival (OS) rates were 11.7% and 35%, respectively; and the 5-year DFS rates and OS rates 11.7% and 23.3%, respectively. The median DFS and OS periods were 12 months (range 2-36 months) and 17 months (range 7-96 months), respectively. The rates of development of local, regional, and systemic recurrences were 20%, 50%, and 80%, respectively. Lungs were involved in all patients who had distant metastasis.

CONCLUSIONS

This study shows that HNMMs has a very aggressive course and that distant metastases are common. For this reason, systemic control of the disease is an important aim of treatment.

Update on primary head and neck mucosal melanoma

Primary mucosal melanomas (PMMs) of the head and neck are uncommon malignancies that arise mainly in the nasal cavity and paranasal sinuses, followed by the oral cavity. The mainstay of treatment is radical surgical resection followed by adjuvant radiotherapy in selected patients with high-risk features. Multimodality therapy has not been well studied and is not standardized. Adjuvant radiotherapy seems to improve locoregional control but does not improve overall survival (OS). Elective neck dissection is advocated in patients with oral PMM. Systemic therapy should be considered only for patients with metastatic or unresectable locoregional disease. Despite improvements in the field of surgery, radiotherapy, and systemic therapy, patients with PMM still face a very unfavorable prognosis (5-year disease-free survival [DFS] <20%) with high rates of locoregional recurrence and distant metastasis. The present review aims to summarize the current state of knowledge on the molecular biology, pathological diagnosis, and management of this disease.

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.

Clinicopathological characterization of primary oral and sinonasal melanoma in a referral centre in Mexico City: 2000-2012

In Mexico, there have been few studies on primary oral and sinonasal melanoma, an aggressive neoplasm with a low survival rate and few therapeutic alternatives. Further, there is limited information about its clinical and histopathological characteristics. The aim of this retrospective study was to describe the clinicopathological profile of these tumours in patients attending a major oncology reference centre in Mexico City over a 12-year period. Demographic and clinical data were obtained from the clinical charts, and histopathological features were evaluated. χ(2), Fisher's exact, and Mann-Whitney U-tests were used for analysis; significance was set at P<0.05. Thirty-three cases were studied (73% sinonasal melanoma (SNM) and 27% oral melanoma (OM)); 58% were female and the median age was 66 (Q1-Q3 55.5-75) years. Compared with OM patients, SNM patients had a shorter time to diagnosis (16.7 vs. 11.7 months, P=0.022), were identified at earlier stages (33.3% vs. 58.3%, P=0.010), and all presented symptoms (66.7% vs. 100%, P=0.015). All samples showed vertical growth and 96.9% exhibited pleomorphism. A higher proportion of cases with pleomorphism developed metastases at follow-up than those without (60% vs. 12.5%, P=0.026). The present study provides valuable information that could form the basis of future studies in the search for advanced therapy modalities.

Gastric metastases from invasive primary mucosal epithelioid malignant melanoma of the hard palate: report of the first case in the English literature

Melanocytes arise from the neural crest and migrate to the epidermis, meninges, uveal tract and ectodermal mucosa. Normal gastric mucosa lacks melanocytes. A 64-year-old woman presented to us with nausea and vomiting. She had a past history of invasive primary mucosal epithelioid malignant melanoma of the hard palate 21 months ago, treated by a wide surgical excision. Gastroscopy revealed multiple punched out ulcers involving the stomach and the first part of duodenum. Immunohistology and clinicopathologic correlation established the diagnosis of metastatic gastric malignant melanoma. To our knowledge, this is the first report in the English literature about gastric metastases arising from primary palatal mucosal melanoma.

Establishment and characterization of an oral mucosal melanoma cell line (MEMO) derived from a longstanding primary oral melanoma

Oral mucosal melanoma is rare. Its incidence peaks between 41 and 60 years of age; male/female ratio is 2:1. Preferred oral sites include hard palate and maxillary gingiva. Risk factors have not been clearly identified, but pigmented lesions may be present before the diagnosis of oral melanoma. We report an unusual case of oral mucosal melanoma of long-standing duration on hard palate and maxillary alveolar ridge in a male patient. Histopathologic features confirmed the diagnosis of invasive melanoma with a prominent in situ component. A cell lineage derived from the tumor was established and characterized, with phenotypic markers of melanocytes.

Heparanase expression correlates with poor survival in oral mucosal melanoma

Oral mucosal melanoma (OMM) is a lethal cancer with a poor prognosis. Despite the great interest in heparanase (HPSE) as a potential anticancer therapy target, the prognostic role of HPSE in oral mucosal melanoma has not been elucidated. In this study, we investigated HPSE expression in OMM tissues and examined its association with clinical outcome. A total of 81 patients with OMM were enrolled in this study. We examined the expression of HPSE in OMM, and its staining extent, intensity and cellular localization were analyzed for clinical significance. HPSE staining was positive in 81 % of tumors (66 of 81 patients) and was negative in the remaining 19 % (15 patients). The median survival time and the 5-year survival rate were 12 months and 7.0 % in the high-heparanase group, 35 months and 36.4 % in the low-heparanase group and 62 months and 53.3 % in the none-heparanase group (P = 0.001). In univariate survival analysis of oral mucosal melanoma, AJCC Stage, heparanase level, heparanase location and tumor size were the clinical parameters related to overall survival. In Cox analysis, overall survival time was significantly dependent on AJCC stage and heparanase level, but not tumor size and heparanase location. Heparanase is frequently expressed in oral mucosal melanoma, and its expression levels inversely correlate with the survival rates of OMM patients, clearly indicating that heparanase is a reliable prognostic factor for this malignancy and an attractive target for anticancer drug development.

Cisplatin and 4-hexylresorcinol synergise to decrease metastasis and increase survival rate in an oral mucosal melanoma xenograft model: a preliminary study

The present study was undertaken to examine the effects of cisplatin plus 4-hexylresorcinol (4-HR) combination therapy on oral mucosal melanoma (OMM) using cultured primary OMM cells in a tumour xenograft model. Cultured primary OMM cells were used for the MTT assay and DNA microarray. OMM cells were implanted into the submandibular glands of nude mice. The mice were then treated with cisplatin only or cisplatin plus 4-HR. Tumour size changes, survival rate and tumour metastasis were compared between the two groups by observation, micro-positron emission tomography (PET) and histological examination. In the MTT assay, the cisplatin plus 4-HR group showed significantly higher inhibition of OMM cell growth compared to the other groups (p<0.05). DNA microarray results showed significant inhibition of matrix metalloproteinase (MMP)-2 gene expression upon 4-HR application. The necropsy and micro-PET results showed that the mice from the cisplatin-only group had more distant metastases than the mice from the cisplatin plus 4-HR combination group (p=0.002). MMP-2 expression was lower in the primary tumours in the cisplatin plus 4-HR combination group than in the cisplatin-only group (p<0.001). Overall survival was longer in mice from the cisplatin plus 4-HR combination group than in the cisplatin-only group (p=0.049). In conclusion, the combined effect of cisplatin and 4-HR resulted in fewer metastases and longer survival than cisplatin-only treatment in the OMM xenograft model.

A case of oral mucosal melanoma. Clinical and dermoscopic correlation

BACKGROUND

Most patients with oral mucosal melanoma have had a mucosal hyper pigmented area for months or even years before the diagnosis, it is important to consider the differential diagnosis of mucosal melanoma, which in many cases is a difficult diagnosis and because of the aggressive biological behavior of mucosal melanoma it is important to do a quick diagnosis.

MAIN OBSERVATION

A 40-year-old Mexican male patient, presented with a lesion on the lower right half of the lip covering almost the entire vermillion border, 1 mm below the white roll. The lesion was a 1.5 x 4 cm pigmented macule with asymmetric and irregular borders and colors. Dermoscopy showed a multi component pattern. An incision biopsy was performed under the impression of mucosal melanoma. The pathologic report described a Clark I vermillion edge mucosal melanoma in situ.

CONCLUSIONS

This case had confounding clinical signs that could have misguided the clinician. But dermoscopy proved to be useful when suspecting a malignant lesion, which prompted a biopsy and a correct diagnosis.

Primary oral melanoma: a histopathological and immunohistochemical study of 22 cases of Latin America

OBJECTIVE

The aim of this study was to analyze the histopathological and immunohistochemical characteristics of 22 cases of primary oral melanomas (OM).

STUDY DESIGN

Twenty two cases of primary oral melanoma were analyzed by description of their histopathological features and immunohistochemical study using the antibodies S-100, HMB-45, Melan-A and Ki-67.

RESULTS

The mean age was 58 years and 14 cases were female. The main affected sites were the hard palate, followed by the upper gingiva. Microscopically, 15 cases presented level III of invasion, 2 cases were amelanotic and 13 showed a mixed epithelioid and plasmacytoid or spindle cells composition. Some cases showed necrosis, perivascular and perineural invasion. S-100 and HMB-45 were positive in all cases, but 3 cases were negative for Melan-A. The proliferative index with Ki-67 was high, with labeling index ranging from 15.51% to 63% of positive cells.

CONCLUSION

S-100 and HMB-45 are more frequently expressed than Melan-A in primary oral melanomas and these markers are helpful to confirm the diagnosis.

Primary nasal mucosal melanoma in Brazil: clinicopathologic and immunohistochemical study of 12 patients

Primary nasal melanoma is a rare tumor of unknown etiopathogenesis that occurs in adult and elderly patients usually diagnosed at advanced stages. The aim of this study was to analyze the clinicopathologic and immunohistochemical characteristics of 12 cases of primary nasal melanomas in Brazil. Twelve cases of primary nasal melanoma were analyzed histologically and by immunohistochemistry using the antibodies S-100 protein, HMB-45, Melan-A, CD63 (NKI/C3), CD68/KP1, fatty acid synthase (FASN), and Ki-67. The mean age of the patients was 60 years, and 7 of 12 patients were men. Microscopically, 10 cases presented level III of invasion; 4 were amelanotic; and in 7, cells were epithelioid. S-100 protein and FASN were positive in all cases, whereas 9, 8, 7, and 6 cases were positive for HMB-45, Melan-A, CD63 (NKI/C3), and CD68/KP1, respectively. Ki-67 labeling index ranged from 11.45% to 28.5% of positive cells. S-100 protein is more frequently expressed in nasal melanomas than in HMB-45, Melan-A, CD63 (NKI/C3), and CD68/KP1. FASN seems to be involved in the pathogenesis of nasal melanomas, and also, it can be helpful to confirm the diagnosis.

Report of a rare and aggressive case of oral malignant melanoma

Background

Oral melanoma is a very rare malignancy with unknown etiology. Its higher incidence is between 41 and 60 years of age. A high localization of oral melanoma was found in the maxilla. Gender distribution was reported as 1:1. Oral melanoma represents 0.2% to 8% of the all the total cases of melanoma of the body.

Case report

In this article we report an aggressive case of oral melanoma in a 71-year-old male with chief complaint of black swelling of the gingiva, paresthesia, and denture ill fitting.

Discussion

Most oral melanomas are asymptomatic and painless in early stages and unfortunately diagnosis delayed until symptoms occurred. Early detection of suspected melanotic lesions by patient, dentist, and physician is very important.

Oral melanotic macule and primary oral malignant melanoma: epidemiology, location involved, and clinical implications

BACKGROUND

Oral malignant melanoma must be differentiated from melanotic macule.

STUDY DESIGN

Retrospective review of 2 series of oral melanotic macule (n = 52) and oral melanoma (n = 130) were conducted to investigate the epidemiology and location involved and assess their differences.

RESULTS

The mean age of oral melanotic macule patients was 47.3 years, with female:male ratio 2.1 and the lower lip being the predominant location. The mean age of oral melanoma patients was 53.8 years, with no observed sex predilection and the main locations being palate and gingiva. Differences between the 2 cohorts in age (P = .006), gender (P = .014), and lesion site (P < .001) were noted. In this review, 1 case of oral melanotic macule was found to subsequently develop into melanoma.

CONCLUSIONS

Oral melanotic macule may possess malignant potential. Biopsy is recommended to differentiate oral melanoma from melanotic macule for male patients >60 years old with suspected melanotic macule lesion located on the palate.

Primary oral mucosal melanoma: advocate a wait-and-see policy in the clinically N0 patient

PURPOSE

Oral mucosal melanoma (OMM) is a rare disease associated with a very poor prognosis. Because well-established treatment protocols for OMM are in short supply, prognostic information regarding recent treatment modalities for this disease were sought.

PATIENTS AND METHODS

A retrospective chart review was performed of 61 patients who were treated for OMM from 1998 through 2005. The clinical features and treatment modalities were identified and correlated with the outcomes.

RESULTS

There were 41 male and 20 female patients (ratio, 2.1:1) with a mean age of 54.1 years. The mean follow-up was 31.9 months, and the overall 2-year and 5-year survival rates were 51.1% and 30.3%, respectively. According to the seventh edition of the American Joint Committee on Cancer staging system, there were 31 patients (50.8%) with stage III tumors. A more advanced stage and a tumor of at least 2 cm were associated with worse survival (P < .001 and P = .036, respectively). Elective lymph node dissection and biochemotherapy were not associated with a higher total survival rate (P = .53 and P = .76, respectively).

CONCLUSIONS

OMM has a male predilection. The seventh edition of the American Joint Committee on Cancer stage and tumor size are effective prognostic parameters for patients with OMM. The American Joint Committee on Cancer staging system provides useful information for predicting the ultimate outcome and should be used as the primary staging system. Elective node dissection and adjuvant biochemotherapy offer no additional advantage in increasing the patient survival rate. A wait-and-see policy is advocated for patients with clinical stage N0 cancer.

Melanoma in children

CONTEXT

Cutaneous melanoma in childhood (CMC) is rare; therefore, its prognostic factors and biologic behavior, and the effectiveness of adjuvant techniques for CMC remain mostly unknown.

OBJECTIVE

To review the most useful, evidence-based practice criteria for establishing the diagnosis of CMC, for which universally accepted criteria are lacking, in order to facilitate the interpretation and comparison of the results from different institutions, and to perform systematic reviews and meta-analysis.

DATA SOURCES

A comprehensive review of the most relevant previous single-institution series reported in the literature since 1990, including our cumulative experience of 137 cases of primary cutaneous and mucosal melanoma in patients younger than 18 years. Special characteristics of melanoma in children are discussed, regarding clinical settings and risk factors, helpful histologic features, and immunohistochemical patterns for diagnosis and prognosis.

CONCLUSIONS

Careful analysis of histologic features as well as the additional information provided by immunohistochemistry should allow for a correct diagnosis in most cases of melanoma in children. Although it seems that pediatric patients with melanoma have higher survival probability than adults, still a number of children will develop metastasis and die of their disease, particularly when melanoma is diagnosed after puberty. Until further studies more accurately determine the prognosis, a prudent approach to CMC diagnosis and therapy seems to follow the same principles as those established for adult melanoma.