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malignant melanoma of oral cavity is an infrequent neoplasm originating from malignant transformation of melanocytes found in the basal layer of oral mucosal membrane .
melanocytes are neural crest - derived cells that migrate to the skin , mucosal membranes , and several other sites .
it represents 0.28% of the total cases of melanoma from the other locations of the body and 0.5% of all oral neoplasia .
a definitive precursor lesion for mucosal melanoma has not been identified ; however , atypical melanocytic hyperplasia may represent a proliferative phase before overt tumorigenesis occurs . mechanical trauma such as dental irritation , tobacco use , exposure to formaldehyde , and alcohol
majority of cases occur after 40 years of age , with a higher incidence in the sixth decade and slightly more male predilection .
the common sites of occurrence are the palate and gingiva , with the maxillary arch being affected 80% of the time .
clinical features include the presence of melanotic pigmentation ( in 30% of cases before diagnosis ) , amelanotic lesions ( up to 20% ) , pain , and bleeding .
the most common sites of metastasis are lymph nodes , lung , bone , liver , and brain .
surgical resection of the lesion with negative margins is the treatment of choice with the ill - defined role of chemo radiotherapy in the adjuvant setting .
it has a poor prognosis with regard to delayed diagnosis , high rates of local relapse , and distant metastasis due to early hematogenous spread .
the present article describes clinical and epidemiological features of 8 patients presented to our department and treatment modalities , as it adds to the natural history of the lesion .
this is a retrospective study of eight cases of oral malignant melanoma that were treated at our institution during august 2012 to october 2014 .
all patients underwent a complete examination , chest x - ray , and computed tomography ( ct ) scan .
the age , sex of patients , tumor location , symptoms , radiological features , final histopathology , treatment modalities , and outcome were recorded [ table 1 ] .
the mean age of patients was 46.8-year - old with a range of 3565 years .
majority of patients were above 40 years with none below the age of 30 years .
majority of patients had a history of tobacco chewing ( 87.5% cases [ 7 patients ] ) and smoking ( 62.5% cases [ 5 patients ] ) whereas none of them had a history of alcohol consumption or exposure to formaldehyde .
most common presenting feature was pigmented lesion ( 87.5% ) , followed by ulcer , pain , and bleeding .
majority of the patients presented with duration of symptoms between 2 and 18 months ( mean duration - 9.4 months ) .
most common site of involvement was hard palate ( 50% cases ) , followed by upper alveolus , lower alveolus , lip and floor of mouth ( fom ) [ figure 1a  f ] .
( a - f ) clinical photographs showing malignant melanoma of the oral cavity affecting various sites orthopantomogram and ct scan were the imaging modalities used to know the site and extent of the tumor [ figure 2a  d ] .
pet scan was done in two patients as a part of staging purpose [ figure 3a and b ] .
majority of patients ( 5 patients [ 62.5% ] ) were diagnosed with stage iii ( distant metastasis ) , two patients in stage ii , and one patient in stage i. most common site of metastasis was regional lymph nodes , lung , followed by bone and liver with breast being one of the rare sites .
diagnosis of all patients was confirmed with punch / incision biopsy [ figure 4 ] .
( a - d ) orthopantomogram and computed tomography scan showed cortical erosion of the mandibular bone ( right side ) ( a ) positron emission tomography scan showing increased tracer activity in the right mandibular region .
( b ) positron emission tomography scan showing extensive skeletal metastasis with increased tracer uptake in hard palate photomicrograph showing a hypercellular tumor with spindle - shaped melanocytes suggestive of malignant melanoma three patients were treated with definitive surgery [ figure 5a and b ] and five patients with palliative chemotherapy in view of distant disease . following surgery , two of them required adjuvant chemoradiotherapy in view of node positivity [ table 2 ] .
( a ) intraoperative photograph showing exophytic pigmented growth arising from mandibular gingiva . ( b ) surgical resection specimen showing a pigmented tumor arising from mandibular gingiva treatment modalities and outcome of 8 patients of oral malignant melanoma patients were followed up for 8 months to 26 months with a mean follow - up of 10.5 months .
patients treated with definitive surgery had a better survival ( 1026 months , mean - 16 months ) , with local recurrence in one patient .
metastatic melanoma patients treated with palliative chemotherapy had a mean disease control rate of 5 months ( range 59 months ) [ table 2 ] .
the mean age of patients was 46.8-year - old with a range of 3565 years .
majority of patients were above 40 years with none below the age of 30 years .
majority of patients had a history of tobacco chewing ( 87.5% cases [ 7 patients ] ) and smoking ( 62.5% cases [ 5 patients ] ) whereas none of them had a history of alcohol consumption or exposure to formaldehyde .
most common presenting feature was pigmented lesion ( 87.5% ) , followed by ulcer , pain , and bleeding .
majority of the patients presented with duration of symptoms between 2 and 18 months ( mean duration - 9.4 months ) .
most common site of involvement was hard palate ( 50% cases ) , followed by upper alveolus , lower alveolus , lip and floor of mouth ( fom ) [ figure 1a  f ] .
( a - f ) clinical photographs showing malignant melanoma of the oral cavity affecting various sites
orthopantomogram and ct scan were the imaging modalities used to know the site and extent of the tumor [ figure 2a  d ] .
pet scan was done in two patients as a part of staging purpose [ figure 3a and b ] .
majority of patients ( 5 patients [ 62.5% ] ) were diagnosed with stage iii ( distant metastasis ) , two patients in stage ii , and one patient in stage i. most common site of metastasis was regional lymph nodes , lung , followed by bone and liver with breast being one of the rare sites .
diagnosis of all patients was confirmed with punch / incision biopsy [ figure 4 ] .
( a - d ) orthopantomogram and computed tomography scan showed cortical erosion of the mandibular bone ( right side ) ( a ) positron emission tomography scan showing increased tracer activity in the right mandibular region .
( b ) positron emission tomography scan showing extensive skeletal metastasis with increased tracer uptake in hard palate photomicrograph showing a hypercellular tumor with spindle - shaped melanocytes suggestive of malignant melanoma
three patients were treated with definitive surgery [ figure 5a and b ] and five patients with palliative chemotherapy in view of distant disease . following surgery , two of them required adjuvant chemoradiotherapy in view of node positivity [ table 2 ] .
( b ) surgical resection specimen showing a pigmented tumor arising from mandibular gingiva treatment modalities and outcome of 8 patients of oral malignant melanoma
patients were followed up for 8 months to 26 months with a mean follow - up of 10.5 months .
patients treated with definitive surgery had a better survival ( 1026 months , mean - 16 months ) , with local recurrence in one patient .
metastatic melanoma patients treated with palliative chemotherapy had a mean disease control rate of 5 months ( range 59 months ) [ table 2 ] .
most common site for head and neck melanoma is conjunctiva , followed by upper respiratory tract .
mucosal melanoma of the oral cavity is the unusual malignancy accounting for 0.28% of all the melanomas affecting the patients .
jackson and simpson have described that melanomas of the oral cavity account for < 2% of all melanomas , while reddy et al . have reported an incidence of 0.31.3% .
it has a poor prognosis due to several characteristics such as remaining asymptomatic for a long time , which leads to its late discovery .
greene et al . described the criteria for primary oral malignant melanoma which includes demonstration of clinical and microscopic evidence of melanoma in the oral mucosa , presence of junctional activity , and inability to demonstrate extraoral primary melanoma .
precursor lesion such as preexisting melanosis or atypical melanocytic hyperplasia may represent a proliferative phase before overt tumorigenesis occurs . mechanical trauma such as dental irritation , tobacco use , exposure to formaldehyde , and alcohol
the average age of the cases studied was 46.8 years , and 75% of patients were above the age of 40 years , which agrees with doval et al . and tanaka et al .
rapidis et al . reported that this disease is unusual before the age of 30 years supporting the above study .
in the present study , there was a male preponderance ( 3:1 ratio ) , which agrees with a review of literature . however , some studies such as studies by lopez - graniel et al . and chidzonga 's et al . have noted female preponderance .
majority of patients in the present study had a history of tobacco chewing ( 87.5% cases ) and smoking ( 62.5% ) .
however , no etiologic factors have been identified for oral melanomas . in comparison to cutaneous or other site melanomas which are believed to arise from a nevus , primary oral melanomas present as pigmented areas or de novo ( 30% cases ) .
oral melanomas are usually asymptomatic and usually present late with symptoms resulting from ulceration , growth , or bleeding .
most of the patients had pigmented lesions / ulceration at presentation ( 7 out of 8 cases ) . around
oral melanomas are highly aggressive in nature due to hematogenous spread early in the course of the disease .
the present study found hard palate as the most frequent site of disease ( 50% cases ) , finding relation with meleti et al .
other less common sites were upper alveolus , lower alveolus , and fom as in the lopez - graneil et al .
's study , who noted 73% cases had disease in hard palate . in our study , most of the patients presented at advanced stage .
five cases had distant metastases ; among them , lung was the most common site of distant metastasis followed by liver and bone .
these results agrees with that of temam et al . , who reported lung metastasis in 53% , bone metastasis in 36% , liver metastasis in 20% , and brain metastasis in 20% cases .
patients were staged according to uicc staging : stage i confined to oral cavity , stage ii to positive cervical nodes , and stage iii to distant metastasis .
one patient had stage i disease and underwent surgery and two patients had stage ii disease at diagnosis and had undergone surgery plus chemoradiotherapy .
most important factors determining oral melanoma prognosis include tumor thickness , depth , and stage at presentation , which is related to poor outcome .
the mainstay of treatment of patients with head and neck mucosal melanomas is surgery , which entails complete resection of the primary tumor and any positive cervical lymph nodes .
any pigmented lesion in oral cavity should have an index of suspicion , which should be investigated to detect the disease at an early stage and managed appropriately .
oral melanomas usually present in advanced stage and carries worse prognosis as compared to cutaneous melanomas .
the main treatment modality is surgical resection , which offers the best chance for long - term survival .
the present study highlights that an early diagnosis and interventions are required to improve the prognosis of the patients .
the authors certify that they have obtained all appropriate patient consent forms . in the form the patient(s )
has / have given his / her / their consent for his / her / their images and other clinical information to be reported in the journal .
the patients understand that their names and initials will not be published and due efforts will be made to conceal their identity , but anonymity can not be guaranteed .
the authors certify that they have obtained all appropriate patient consent forms . in the form the patient(s )
has / have given his / her / their consent for his / her / their images and other clinical information to be reported in the journal .
the patients understand that their names and initials will not be published and due efforts will be made to conceal their identity , but anonymity can not be guaranteed .
background : primary mucosal malignant melanoma is an extremely rare , aggressive neoplasm accounting for 0.5% of all oral malignancies . any pigmented lesion in oral cavity should have an index of suspicion , which should be investigated to detect the disease at an early stage and managed appropriately . 
 melanomas tend to invade locally into the tissue or metastasize more commonly than other malignant tumors of the oral cavity.materials and methods : we report a retrospective case series of eight patients suffering from primary oral malignant melanoma treated in our department between 2012 and 2014 . the details were recorded from the departmental computerized database and patients on follow-up.results:there were six male and two female patients with a mean age of 46.8 years . 
 hard palate was the most common affected site in oral cavity . 
 pigmented lesion\ulcer was the most common presenting symptom . 
 majority of patients ( 5 patients ) were diagnosed with stage iii ( distant metastasis ) , two patients in stage ii , and one patient in stage i. three patients were treated with definitive surgery and five patients with palliative chemotherapy in view of distant disease . following surgery , two of them required adjuvant chemoradiotherapy in view of nodal spread . 
 patients had a mean follow - up of 10.5 months ( range : 826 months ) . 
 patients treated with definitive surgery had a mean survival rate of 16 months ( range : 1026 months ) , with local recurrence in one patient . 
 metastatic melanoma patients treated with palliative chemotherapy had a mean disease control rate of 5 months ( range 59 months).conclusion : oral melanoma carries dismal prognosis with a 5-year survival rate of 520% . 
 early detection of the lesion , proper evaluation , and appropriate treatment are very important to cure the disease .