الفهرس 
Histology of skinOnly 14 pages are availabe for public view
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Abstract
In this essay we have studied malignant melanoma with an account on the definition , incidence aetiology , path-ology clinical presentation , diagnosis treatment and prognosis . The term melanoma refers to a malignant lesion originating in the melanoblasts of the skin The tumour may develop in any area of the skin mucous membrane or pigmented region of the eye . This tumour accounts for 1-3% of all malignant neoplasms and comprises 5 % of all skin cancer ; but the rate of incidence is currently rising faster than any other cancer . Cutaneous malignant melanoma may develop either on top of a pre-existing naevus or skin that has been regularly exposed to the sun . The precuror lesions for malignant melanoma include dysplastic naevi and giant congenital naevocellular naevi . Primary cutaneous malignant melanoma is common in those
aging 54 years and females are commonly affected than males . Also malignant melanoma is more frequent in Caucasians ( Whites ) than in black populations ; while acral lentiginous melanoma was being predominant in blacks . In females ; the leg is the commonest site to be affected and in males it is the trunk . The colour of the gross tumour varies from erythematous in the non pigmented lesion through various shades of brown to black colour . The tumour is characterized by its relative fragi-lity with bleeding on injury .
Microscopically malignant melanoma is characterized by:
a)The cells are either fusiforth or oval with nuclei and cytopl-asm larger than those of the normal melanocytes and mitotic figures are seen .
b)Lymphocytic and sometimes plasma cell infilterate is often quite abundant in the early lesions. Malignant melanoma show early vascular invasion and spread rather than lymphatic spread which occur in advanced cases of melanoma . Also melanoma spreads superficially in the form of satellite lesions in the skin. Primary cutaneous malignant melanoma is classified into 4 types which include ;
i)Lentigo maligna melanoma ;
ii)Superficial spreading melanoma ;
iii)Nodular melanoma and
iv)Acral lentiginous melanoma .
There are 2 micro-staging systems for malignant melanomas which include ;
a)Level of invasion ( Clark’s method ) and
b)Tumour thickness ( Breslow’s method ) .
The most common and frequent clinical presentations of malignant melanoma observed by the patients are growth , change of colour ( especially darkening )and shape of a pre-existing naevus . Other presentations include ; itching , bleeding , inflammation , crusting and oozing or bleeding .
An additional aid to the clinical recognition of malignant melanoma include ;the use of skin surface microscope 2 dermatoscope and computerized image analysis ; but the surest method of diagnosis of malignant melanoma is the histopathological examination of the lesion following excision biopsy . Two tumour markers are proposed for following the course of malignant melanoma . These tumour markers are neurone specific enuolase and serum associated sialic acid .The normal value of each one is 20 mg %
The primary curative therapy for malignant melanoma is surgery Other available modalities include , radiotherapy , chemotherapy and immunotherapy alone or in combination and are at the best palliative at the present time . The prevention of malignant melanoma is done by the use of sunscreens .