Primary malignant melanoma of the mucous membranes

A Retrospective Analysis of the Prognostic Factors and Adverse Events in the Treatment of Mucosal Melanoma in a Single Centre

Background: Despite the dramatic advances in the management of metastatic cutaneous melanoma, there remains no consensus-based, evidence-based strategy for the management of mucosal melanoma. The rare nature of the disease, its late clinical presentation, and distinct tumour biology all complicate efforts to optimise patient outcomes. Methods: To this end, we carried out a monocentric, retrospective analysis of all patients diagnosed with mucosal melanoma and treated between 2013 and 2021. Both tumour- and patient-specific characteristics were recorded, in addition to immune-related adverse events, in order to provide real-world data on disease progression, treatment efficacy, and the identification of prognostic markers. Results: A total of 20 patients were identified (14 females and 6 males), with a mean age at diagnosis of 65.9 years. The median follow-up was 3.9 years (95% CI 1.4-6.4 years) from the initiation of systemic therapy. The median OS in the entire cohort was 1.9 years (95% CI 0.5-3.3 years). Performance status, sex, body mass index, and the presence of brain metastases were not associated with poorer outcomes. However, serum lactate dehydrogenase levels (LDH) (p = 0.04) and an NRAS mutation were markers of a poor prognosis (p = 0.004). Conclusuion: There is a pressing need for real-world, prospective, and clinical trial data to inform the optimal management of mucosal melanoma, and data supporting the use of adjuvant and neo-adjuvant immunotherapy are currently lacking. However, an elevated LDH is a reliable, independent negative prognostic marker. Inter-disciplinary management remains essential in order to develop optimal treatment strategies.

Mucosal Melanoma Clinical Management and Prognostic Implications: A Retrospective Cohort Study

Mucosal melanoma (MM) is an uncommon melanoma subtype affecting mucosal surfaces of the head and neck, anorectal region, and vulvovaginal area. We aimed to present our experience at a tertiary-level hospital regarding MM diagnosis, management, monitoring of progression, mutations, and outcome predictors. We performed a registry-based cohort study including MM cases diagnosed from 2012 to 2022 and retrospectively characterized somatic mutations on BRAF, NRAS and c-KIT. We employed Kaplan-Meier curves, log-rank tests, and Cox regression analysis to explore prognostic factors and survival outcomes in a cohort of 35 patients, mainly women (63%) with a median age of 70 years. Predominantly, MM occurred in the vulvovaginal region (48.6%). At diagnosis, 28.6% had lymph node involvement, and 31.4% also had distant metastasis. Mutations in BRAF and c-KIT were identified in 3/35 (9%) and 2/6 patients (33%), respectively. Surgery was performed in 71.4% of patients, and most received systemic treatment (65.7%). Lower disease stage, thinner Breslow depth, and surgical resection were associated with improved overall survival. Notably, age, sex, radiotherapy, and BRAF mutant status did not affect survival. Standard management typically involves immunotherapy. Cases with BRAF or c-KIT mutations may be considered for targeted therapies. Unfortunately, MM prognosis remains unfavorable, with a less than 50% survival rate at 2 years.

Primary colonic melanoma: a rare entity

Gastrointestinal melanoma is usually metastatic in origin, and primary melanoma within the gastrointestinal tract is rarely reported. Colon is considered to be an extremely uncommon site for primary melanomas. Herein, we report the first case of a large primary melanoma within the transverse colon with gastric involvement. CT scan found a mass within the colon, which seemed to connect to the gastric antrum. Esophagogastroscopy showed an ulcerated lesion in the greater curvature of the stomach. Subsequent colonoscopy identified a large ulcerated lesion rendering significant stenosis of the transverse colon. Biopsy following colonoscopy indicated a diagnosis of colonic melanoma based on pathological findings, which identified submucosal malignant melanoma cells with epithelioid and spindle features. Immunohistochemical stains were positive for S-100, HMB-45, Vimentin, and Melan-A. A series of clinical and imaging examinations revealed no suspicious primary cutaneous or ocular lesions. The diagnosis of primary colonic melanoma was considered. A radical transverse colectomy with subtotal gastrectomy were conducted subsequently. Definite diagnosis of primary colonic melanoma can be established after ruling out the possibility of being a metastasis from other more common primary sites. Primary colonic melanomas are a challenge to diagnose and often need a multidisciplinary treatment approach, including surgery, BRAF-targeted therapy, and immunotherapy.

Proliferation Marker Ki67 as a Stratification Index of Adjuvant Chemotherapy for Resectable Mucosal Melanoma

Background

Adjuvant chemotherapy has been shown to produce a favorable prognosis for patients with resectable mucosal melanoma (MM), resulting in the need for stratification to optimally select patients to benefit from adjuvant therapy. This study analyzed Ki67 as a potential stratification index for adjuvant chemotherapy in resectable MM.

Methods

Patients with resected MM who received subsequent adjuvant therapy in Beijing Cancer Hospital between 2010 and 2018 were retrospectively enrolled and analyzed. Relapse-free survival (RFS) and melanoma-specific survival (MSS) curves were used to perform the survival comparisons across different subgroups.

Results

From Jan 2010 to Dec 2018, 1106 MM patients were screened from a database of 4706 patients and 175 of these patients were finally enrolled. A total of 100 patients received temozolomide (TMZ)-based adjuvant chemotherapy and 75 patients received high-dose interferon-α2b (HDI) adjuvant therapy. Compared with HDI, patients who received TMZ-based adjuvant chemotherapy had significantly superior RFS (21.0 vs. 9.6 months, P = 0.002). For patients with low Ki67 expression (<30%), the two regimens showed no significant difference for impact on RFS (33.9 vs. 22.7 months, P = 0.329). However, for patients with high Ki67 expression (≥30%), TMZ-based adjuvant chemotherapy achieved favorable RFS compared with HDI (18.0 vs. 6.7 months, P < 0.001) and tended to improve MSS compared to HDI (41.4 vs. 25.1 months, P = 0.067).

Conclusion

Compared with HDI, adjuvant chemotherapy may be more relevant for patients with Ki67 ≥ 30%. Ki67 may serve as a potential index to distinguish populations benefiting from adjuvant chemotherapy in resectable MM, and may provide a basis for stratification in the selection of adjuvant regimens.

Epidemiology and outcomes of gastrointestinal mucosal melanomas: a national database analysis

Aim

Gastrointestinal malignant melanoma is a rare mucosal melanoma (MM). Other MM include the respiratory and the genitourinary tract. All mucosal melanomas have a poor prognosis when compared to cutaneous melanomas. Ano-rectal melanomas are by far the most common and most studied gastrointestinal MM. Large-scale clinical data is lacking due to the rarity of the disease. We aim to analyze epidemiology and survival of the Gastrointestinal (G.I.) MM over 45 years using a national database.

Methods

The Surveillance, Epidemiology and End Results (SEER) database was queried to identify patients with biopsy-proven G.I. Melanomas. We selected tumor site, intervention, and survival information for oncology codes as per the international classification of diseases. Survival analysis was performed using the SPSS v 27 ® IBM software.

Results

Of the 1105 biopsy-proven confirmed cases of primary G.I. melanoma's, 191 (17.3%) received chemotherapy (C.T.), 202 (18.3%) received radiotherapy (R.T.), 63 (5.7%) received both C.T and R.T., while 684 (61.9%) of the population received surgery alone or combined with C.T. and/or R.T. Statistically significant improvement in survival was noted in all treatment strategies that utilized surgery and also when site-specific MM cohorts underwent a surgical approach with or without C.T and/or R.T.

Conclusion

This is the most extensive study reporting epidemiological and survival data of treatment strategy outcomes of primary G.I. mucosal melanoma elucidating best overall survival with a management strategy involving surgical intervention.

Genetic drivers of non-cutaneous melanomas: Challenges and opportunities in a heterogeneous landscape

Non-cutaneous melanomas most frequently involve the uveal tract and mucosal membranes, including the conjunctiva. In contrast to cutaneous melanoma, they often present at an advanced clinical stage, are associated with worse clinical outcomes and show poorer responses to immunotherapy. The mutational load within most non-cutaneous melanomas reflects their lower ultraviolet light (UV) exposure. The genetic drivers within non-cutaneous melanomas are heterogeneous. Within ocular melanomas, posterior uveal tract melanomas typically harbour one of two distinct, sets of driver mutations and alterations of clinical and biological significance. In contrast to posterior uveal tract melanomas, anterior uveal tract melanomas of the iris and conjunctival melanomas frequently carry both a higher mutational burden and specific mutations linked with UV exposure. The genetic drivers in iris melanomas more closely resemble those of the posterior uveal tract, whereas conjunctival melanomas harbour similar genetic driver mutations to cutaneous melanomas. Mucosal melanomas occur in sun-shielded sites including sinonasal and oral cavities, nasopharynx, oesophagus, genitalia, anus and rectum, and their mutational landscape is frequently associated with a dominant process of spontaneous deamination and infrequent presence of UV mutation signatures. Genetic drivers of mucosal melanomas are diverse and vary with anatomic location. Further understanding of the causes of already identified recurrent molecular events in non-cutaneous melanomas, identification of additional drivers in specific subtypes, integrative multi-omics analyses and analysis of the tumor immune microenvironment will expand knowledge in this field. Furthermore, such data will likely uncover new therapeutic strategies which will lead to improved clinical outcomes in non-cutaneous melanoma patients.

Mucosal Melanoma: Epidemiology, Biology and Treatment

Mucosal melanoma is an exceedingly rare variant of cutaneous melanoma that, due to its rarity, is poorly described and infrequently studied. Primary sites of origin include the head and neck, anorectum and vulvovaginal regions. It is uniquely different from cutaneous melanoma with respect to epidemiology, etiology, pathogenesis and prognosis. The etiology and pathogenesis remain unclear. Unlike cutaneous melanoma, exposure to UV light is not an apparent risk factor. Furthermore, distinct molecular features including a lower incidence of BRAF oncogene mutations but a higher incidence of KIT oncogene mutations suggest divergent genetic etiologies. Mucosal melanomas generally present at a later stage, are more aggressive and carry a worse prognosis regardless of the stage at diagnosis. Establishing standardized treatment guidelines has been challenging due to the rarity of the disease. Early detection provides the best chance at survival but is often difficult due to anatomic location. Surgery remains the primary therapeutic intervention if complete resection is technically feasible given the anatomic location. Radiotherapy may be used to achieve local control when resection is not feasible, or adjuvantly to enhance locoregional control, but most studies have failed to demonstrate an improvement in overall survival. There are no consensus guidelines on the optimal systemic therapy, and regimens are often extrapolated from data based on therapies used to treat advanced cutaneous melanoma. Clinical trials, particularly utilizing newer targeted therapies and immunotherapies, are investigating novel treatment approaches.

Comparison of Melanoma Subtypes among Korean Patients by Morphologic Features and Ultraviolet Exposure

Background

Genetic alterations have been identified in melanomas according to different levels of sun exposure. Whereas the conventional morphology-based classification provides a clue for tumor growth and prognosis, the new classification by genetic alterations offers a basis for targeted therapy.

Objective

The purpose of this study is to demonstrate the biological behavior of melanoma subtypes and compare the two classifications in the Korean population.

Methods

A retrospective chart review was performed on patients found to have malignant melanoma in Severance Hospital from 2005 to 2012. Age, sex, location of the tumor, histologic subtype, tumor depth, ulceration, lymph node invasion, visceral organ metastasis, and overall survival were evaluated.

Results

Of the 206 cases, the most common type was acral melanoma (n=94, 45.6%), followed by nonchronic sun damage-induced melanoma (n=43, 20.9%), and mucosal melanoma (n=40, 19.4%). Twenty-one patients (10.2%) had the chronic sun-damaged type, whereas eight patients (3.9%) had tumors of unknown primary origin. Lentigo maligna melanoma was newly classified as the chronic sun-damaged type, and acral lentiginous melanoma as the acral type. More than half of the superficial spreading melanomas were newly grouped as nonchronic sun-damaged melanomas, whereas nodular melanoma was rather evenly distributed.

Conclusion

The distribution of melanomas was largely similar in both the morphology-based and sun exposure-based classifications, and in both classifications, mucosal melanoma had the worst 5-year survival owing to its tumor thickness and advanced stage at the time of diagnosis.

Mucosal melanomas in the elderly: challenging cases and review of the literature

Melanomas are malignant tumors that originate from melanocytes. They are most frequently localized in the skin, but 5% of all melanomas interest also extracutaneous sites as mucosal surfaces, parenchymatous organs, the retroperitoneum area, and the ocular ball. The purpose of this study was to investigate the epidemiologic and morphologic data of mucosal melanomas diagnosed at Emergency City Hospital (Timisoara, Romania) during a period of 12 years. The study included 17 cases of extracutaneous, extraocular melanomas, with 16 primary melanomas and one secondary melanoma. All our patients were older than 53 years and were mostly men. Most of the patients presented with localized disease; only one case had regional lymph node metastases, and another one had systemic metastases at the time of diagnosis. Regarding localization, nine of 16 melanomas were in the head and neck region, six were diagnosed in the gastrointestinal and urogenital tracts (three cases each), and one case had a rare localization (retroperitoneum). The most common histologic type was represented by epithelioid cells, and the majority of the tumors were achromic. Mucosal melanoma is a tumor associated with aging, all our patients being older than 53 years. Because of unspecific symptoms and low incidence, the diagnosis is often delayed and requires teamwork among the clinician, pathologist, radiologist, and oncologist. Different genetic fingerprints impose a correct diagnosis to offer the patient the best novel, personalized therapy.

Noncutaneous melanoma have distinct features from each other and cutaneous melanoma

OBJECTIVE

Compared to the cutaneous melanoma, noncutaneous melanomas are relatively rare and have a distinct pattern of behavior. We performed this study to define the clinical characteristics and outcomes of patients with noncutaneous melanomas and emphasize how they differ from cutaneous melanomas.

METHODS

216 patients who were diagnosed with noncutaneous melanoma were assessed and their medical records between 2000 and 2010 were retrieved from the cancer registry. 475 patients with cutaneous melanoma were used for comparison.

RESULTS

Of the 216 noncutaneous melanoma patients, 83 had mucosal melanoma, 101 had ocular melanoma and 32 had unknown primaries. For mucosal melanoma, the head and neck was the most common anatomic site (53%), followed by the gastrointestinal tract (37%), female genital (6%) and urinary tract (4%). The majority of the ocular melanomas (94%) originated in the uvea. 32 patients demonstrated a primary unknown disease with regional metastasis as the dominant behavior (72%). Age was found to be statistically significantly different among melanoma patients (p < 0.001). Younger patients had more cutaneous and unknown primary melanomas, whereas older patients had more ocular and mucosal melanoma. In subset analyses, we found significant differences between cutaneous and ocular (p = 0.038) or mucosal (p < 0.001) melanomas. The ratios of metastasis on admission were higher in patients with mucosal (27.7%) and unknown primary (28.1%) melanomas, and lower for ocular (3%) melanomas (p < 0.001). Patients with cutaneous melanoma had an intermediate (12%) ratio. Patients with ocular melanoma had better outcome than patients with other melanoma sites (p < 0.05). While overall survival for cutaneous melanoma was significantly negatively correlated with male gender (p < 0.001), advanced stages (p < 0.001) and old age (p = 0.005), stage IV disease was the only independent prognostic factor in patients with ocular melanoma (p = 0.006). No prognostic factor for outcome was found for either mucosal or unknown primary melanomas.

CONCLUSION

The clinical presentations and prognoses of different primary sites of melanoma are distinctive. Therefore, approaches to these melanomas should be different.

Anal melanoma

Anal melanoma is rare and aggressive malignancy. Patients commonly present with advanced, even metastatic disease. Unlike cutaneous melanoma, anal melanoma has no known risk factors. Surgical excision remains the cornerstone of therapy. There are no long-term survivors of stage II or III disease; therefore, early diagnosis and treatment remain crucial. There are no trials definitively proving abdominal perineal resection (APR) or wide local excision (WLE) to yield superior long-term survival. APR may offer a higher rate of local control, whereas WLE offers a much less morbid operation. Adjuvant chemotherapy, interferon, and radiation may offer some benefit.

Mucosal melanomas: a case-based review of the literature

Mucosal melanoma is a rare cancer that is clearly distinct from its cutaneous counterpart in biology, clinical course, and prognosis. Recent studies have shown important differences in the frequencies of various genetic alterations in different subtypes of melanoma. Activating mutations in the c-KIT gene are detected in a significant number of patients with mucosal melanoma. This observation has resulted in the initiation of several clinical trials aimed at exploring the role of receptor tyrosine kinases that inhibit c-KIT in this patient population. We herein present a comprehensive literature review of mucosal melanoma along with case vignettes of a number of pertinent cases. We further discuss melanomas of the head and neck, the female genital tract, and the anorectum, which are the three most common sites of mucosal melanoma, with a particular focus on the diagnostic, prognostic, and therapeutic data available in the literature.

Nasal mucosal melanoma presenting as central type vertigo: a case report

Nasal mucosal melanoma presents usually with epistaxis, nasal obstruction and facial pain. However melanoma tends to give distant metastases at an early stage, having rare clinical presentations.

We present a 74-year old female patient with symptoms of central type vertigo caused by brain metastases. Clinical assessment for the detection of the primary site revealed a nasal mucosal melanoma originating from the posterior end of the left inferior turbinate. The patient received a combination of radio and chemotherapy being in relatively good condition 8 months later. This is the first reported case of a nasal mucosal melanoma with vertigo as the first presenting symptom.

Extracutaneous malignant melanomas

Extracutaneous malignant melanomas are rare tumors with vexing clinical presentation and grim prognosis. Only 4%-5% of all primary melanomas do not arise from the skin. These tumors are almost uniformly fatal, even in 2006. Although a fairly good number of these lesions were reported in the literature, the lack of a side-by-side analysis of these studies has resulted in tentative conclusions that merely offer a first glimpse at the clinicopathologic diversity of these lesions. To remedy this issue, this article took an aim at presenting a literature review concerning extracutaneous malignant melanomas. It also reports several cases of extracutaneous melanomas, which I came across in my 15 years of surgical and molecular pathology practice. The study raises several notions. Extracutaneous malignant melanomas are rare but extremely aggressive lesions with a grim outcome. They include ocular, metastatic, anorectal, mucosal, nail beds, conjunctival, vaginal, urogenital, orbital, esophageal, and leptomeningial malignant melanomas. The development of these lesions lacks an association with sun damage, family history, or precursor nevi. These lesions cause considerable diagnostic consternation and their distinction from other types of tumors (such as undifferentiated carcinomas, high-grade sarcomas, and lymphomas) is critical both from a diagnostic and prognostic point of view. In the proper clinical, histological, and cytological context, immunopositivity for S100 protein, HMB45, and vimentin allows the distinction of these malignant melanomas from other histologically similar malignancies. To conclude, extracutaneous melanoma should be considered while undifferentiated neoplasms, especially those displaying prominent eosinophilic nucleoli, and the coexistence of epithelioid and spindle cells. Special staining and immunohistochemistry should be resorted to establish the diagnosis.

Effect of peripheral endothelin-1 concentration on carcinoma-induced pain in mice

In this study, we investigated the role of the peripheral endothelin-1 (ET-1) concentration in a cancer pain model. To test the hypothesis that the concentration of ET-1 in the tumor microenvironment is important in determining the level of cancer pain we used two cancer pain mouse models that differed significantly in production of ET-1. The two mouse cancer models were produced by injection of cells derived from a human oral squamous cell carcinoma (SCC) and melanoma into the hind paw of female mice. Pain, as indicated by reduction in withdrawal thresholds in response to mechanical stimulation, was significantly greater in the SCC group than the melanoma group. The peripheral concentration of ET-1 within the cancer microenvironment was significantly greater in the SCC group. Intra-tumor expression of both ET-1 mRNA and ET-1 protein were significantly higher in the SCC model compared to the melanoma model. ET receptor antagonism was effective as an analgesic for cancer pain in the SCC model only. To address the potential confounding factor of tumor volume we evaluated the contribution of tumor volume to cancer pain in the two models. The mean volumes of the tumors in the melanoma group were significantly greater than the tumors in the SCC group. In both groups, the pain level correlated with tumor volume, but the correlation was stronger in the melanoma group. We conclude that ET-1 concentration is a determinant of the level of pain in a cancer pain mouse model and it is a more important factor than tumor volume in producing cancer pain. These results suggest that future treatment regimens for cancer pain directed at ET-1 receptor antagonism show promise and may be tumor type specific.

Prognosis of Primary Mucosal Penile Melanoma: A Series of 19 Dutch Patients and 47 Patients from the Literature

OBJECTIVES

To analyze the clinical features, prognostic factors, and survival of male patients with primary mucosal melanoma on the glans penis, meatus, fossa navicularis, and distal urethra.

METHODS

We analyzed the clinical features, prognostic factors, and survival of 66 male patients with primary mucosal melanoma on the glans penis, meatus, fossa navicularis, and distal urethra diagnosed over the past 25 years. Data from our series of 19 patients were combined with those of 47 patients reported in the literature.

RESULTS

The overall 2 and 5-year survival rates were 63% and 31%, respectively. All patients with nodal and/or distant metastases at presentation died within 2 years. Presence of ulceration, tumor depth of 3.5 mm or more, and tumor diameter greater than 15 mm had a significantly adverse effect on prognosis.

CONCLUSIONS

The prognosis of primary mucosal penile melanoma is not worse than that for cutaneous melanoma with comparable tumor thickness. Treatment should be similar to that for cutaneous melanoma, with wide radical excision and sentinel node biopsy in clinically lymph node-negative patients.

Primary Malignant Melanoma of the Epiglottis: A Rare Presentation

Primary malignant melanoma of the epiglottis is extremely rare. Until now, only 4 cases have been reported in the world literature. We describe a new case of epiglottic primary malignant melanoma in a 74-year-old man who presented with hoarseness and a foreign-body sensation. Clinical examination revealed the presence of a small, whitish, polypoid tumor on the laryngeal surface of the epiglottis; no other primary melanoma was detected. Wide excision of the lesion was performed, and microscopy revealed that it contained melanin-pigmented tumor cells in both the mucosa and submucosa. Immunostaining was positive for S-100 protein. The patient was treated with radiotherapy, and he remained well 1 year after the diagnosis with no evidence of recurrence.

Primary malignant melanoma of the vagina: a case report and review of the current treatment options

A case with primary malignant melanoma located in the posterior lower third of the vagina was encountered and treated by surgery, postoperative immunotherapy and chemotherapy. The tumor was close to the anal sphincter and posterior exenteration was done to achieve tumor-free surgical margins. The need for such radical treatment prompted us to review the literature and discuss our case with the rarest localization of the tumor in the vagina. We focused on the treatment options and the possible complication that may arise during the treatment of the primary malignant melanoma of the vagina. The need for radical surgery was discussed and the current treatment options were reviewed.

Biochemotherapy in patients with metastatic anorectal mucosal melanoma

BACKGROUND

Patients with metastatic anorectal melanoma generally have an unfavorable prognosis, but no effective systemic therapy has been reported.

METHODS

The authors retrospectively evaluated the medical records of all patients with metastatic anorectal melanoma treated with biochemotherapy between January 1991 and December 2001 at the University of Texas M. D. Anderson Cancer Center (Houston, TX).

RESULTS

The search yielded 18 patients. Of these patients, 14 had undergone treatment with cisplatin (CDDP), vinblastine (VB), dacarbazine (DTIC), interferon alpha-2b (IFN), and interleukin 2 (IL-2); 2 had undergone treatment with CDDP, VB, DTIC, and IFN; 1 had undergone treatment with CDDP, IFN, and IL-2; and 1 had undergone treatment with CDDP, VB, temozolomide, IFN, and IL-2. All IL-2 treatments were administered intravenously. The median follow-up time was 12.2 months (range, 3.5-43.7 months). Eight patients (44%) had major responses, including two (11%) complete responses (CRs). Three patients were lost to follow-up evaluation after the completion of treatment. The median time to progression among the 15 remaining patients was 6.2 months. Four patients, including 1 with a CR, were alive at their last documented follow-up visits (survival: 14.0, 20.7, 31.3, and 43.7 months, respectively). The median overall survival was 12.2 months. Among 13 patients who received biochemotherapy as first-line systemic therapy, 6 patients (46%) had major responses, including two (15%) CRs. The median time to progression for this group was 6.2 months, and the median overall survival was 12.9 months.

CONCLUSIONS

Biochemotherapy had substantial activity against metastatic anorectal melanoma and should be considered for use in the treatment of metastatic disease from primary anorectal melanoma.

Mucosal melanomas

Cutaneous malignant melanoma is a common malignancy and has been increasing at an alarming rate in the United States. Sun exposure is a well-known risk factor related to this disease and much is understood regarding the etiology and epidemiology of cutaneous melanomas. In contrast, primary mucosal melanomas represent an extremely rare malignancy and do not have the same risk factors or behavior patterns. They occur in areas that have no sun exposure and solid predisposing risk factors have not been identified, making this disease very difficult to diagnose or screen for. It is usually diagnosed at a later stage and carries a poor prognosis. Identifying the differences between a primary lesion and a metastatic melanoma is often challenging, because of the lack of definitive criteria, both pathologically and clinically. The rich vascular and lymphatic network surrounding these lesions may be responsible for their aggressive behavior and poor prognosis. In addition, the obscure locations where mucosal melanomas occur are an obvious reason why these lesions often go unnoticed until symptoms develop. Recent literature has raised significant questions regarding recommended treatment strategies. Earlier reports advocated radical surgery as the mainstay of therapy; however, local recurrence and survival were unchanged whether radical surgery or local excision was performed, and the most recent data are favoring the conservative approach when appropriate. Unfortunately, a multitude of adjuvant therapies have been tried without any success. Adjuvant radiotherapy plays a role when combined with surgery, particularly in the head and neck region and female genitalia, but this is reserved for nodal and locoregionally advanced disease and has had no effect when used as a prophylactic method. It is difficult to make significant advances in treatment strategies because of the rarity of the disease. As an example, one in 75 persons born in the year 2000 will develop cutaneous melanoma in his lifetime, compared with four cases per ten million people diagnosed with mucosal melanoma per year in the United States. Possible new therapies based on new biologic and immunologic findings may have future promise on being able to impact this disease. Until then, this aggressive tumor continues to have a poor prognosis, and surgical resection continues to be the mainstay of primary therapy.

Primary malignant mucosal melanoma of the head and neck region: pooled analysis of 60 published cases from India and review of literature

Malignant melanoma arising in the head and neck mucosa is a rare entity with incidence ranging from 2% to 10%. Because of the lack of data, the biological behaviour of these lesions still remains unpredictable and outcome dismal. We carried out a literature review for cases of mucosal melanoma of the head and neck reported from India and performed a pooled analysis on the available data. A total of 60 cases of head and neck melanomas were reported, of which 46 were in men. Palate and alveolus were the commonest sites. A total of 29 (48.3%) patients had regional node metastasis at presentation while five (12%) had distant metastasis. Three-year overall survival of 27.7% was observed. However, the disease-free survival rates at 3, 5 and 6 years were 39.4%, 39.4% and 13.1%, respectively. Metastasis at presentation and use of adjuvant radiotherapy were found to be the only significant predictors of survival. Malignant mucosal melanoma has aggressive biological behaviour and poor outcome. Radical surgery and adjuvant radiotherapy may provide a better local control and may help in improving survival.