Skin cancer facts: Malignant Melanoma

Skin cancer ---> Melanoma skin cancer

Skin Cancers are the most commonly diagnosed malignant tumors in the United States, with an incidence of approximately 1.4 million new cases annually. Basal cell and squamous cell skin carcinoma account for 96% of new non melanoma skin cancers. Malignant Melanoma accounts for 4% of skin cancers.

Risk factors for development of skin melanoma include ultraviolet light (UVL) exposure, fair complexion/inability to tan, blue or green eyes, blonde or red hair, freckling, history of actinic keratosis or non melanoma skin cancer, history of blistering or peeling sunburns, immunosuppression, personal or family history of melanoma, CDKN2A/p16/MC1R mutation, xeroderma pigmentosa, atypical (dysplastic) nevus, more than 100 normal nevi, and giant congenital melanocytic nevus.

The ABCD rule is used to assess skin lesions for melanoma risk: A is for asymmetry; B is border irregularity; C is color, and D is diameter greater than 6 mm.

Melanoma prognosis is inverse correlated to tumor thickness; ulceration and increased mitotic rate are independent survival risk factors; nodal tumor burden (uninvoled versus microscopic versus macroscopic disease) has an inverse correlation with survival.

Treatment: For melanoma in situ, excision margins of 0.5 to 1 cm are indicated; for invasive melanoma, wide excision of the primary tumor with margins generally ranging from 1 to 2 cm is indicated for local control.

Clinically involved lymph nodes should be resected; patients with primary melanomas of 1 mm thickness or greater and clinically negative nodes should be considered for sentinal lymph node biopsy.

Malignant melanoma

Skin cancer ---> Melanoma skin cancer

Melanoma arises from malignant proliferation of melanocytes.
Epidemiology
The incidence of and mortality from melanoma are increasing. Its incidence is approximately 10 per 100 000 per year. The highest incidence occurs in white-skinned individuals in Australia and New Zealand. Melanoma is more common in women than in men.
Pathology
Ultraviolet exposure is a major etiological factor, particularly short, intense exposure resulting in sunburn during childhood. Phenotypic factors associated with melanoma include fair skin, red or blonde hair, blue eyes, inability to tan, freckles, lentigines, large numbers of benign melanocytic nevi and the presence of dysplastic nevi.
Important risk factors for malignant melanoma
Presence of precursor lesions (dysplastic melanocytic nevi)
Family history of melanoma in parents or siblings
Skin phototypes I and II with an inability to tan
Excess sun exposure, especially during childhood
Clinical features
Malignant melanoma has two patterns of growth, radial and vertical. Radial growth is horizontal within the epidermis and superficial dermal layers, as in the lentigo maligna, acral/mucosal lentiginous and superficial spreading types. During this stage of growth the tumor does not have the capacity to metastasize. Vertical growth occurs with time, and the melanoma grows downwards into the deeper dermal layers as an expansile mass, lacking cellular maturation. This correlates with the emergence of a clone of cells with metastatic potential. The nature and extent of this vertical growth phase determine the biological behavior of malignant melanoma. The different types of malignant melanoma are categorized on morphology and histological findings.
Superficial spreading
Superficial spreading is the most common variant of melanoma (70%), presenting as a macule or papule, usually greater than 0.5 cm in diameter. There is variable pigmentation (from pale brown to blue-black), an irregular edge, and surface oozing or crusting. In males it most frequently presents on the back, while in females the leg is the most common site. In the radial growth phase it is characterized by atypical melanocytes, singly and in clusters, widely scattered throughout the layers of the epidermis. Left untreated it may progress to the vertical growth phase over months to years.
Nodular melanoma
Nodular melanoma is the second most common variant (14%) and, by definition, presents in the vertical growth phase. It classically presents as a rapidly enlarging, frequently ulcerated, blue-black nodule.
Lentigo maligna
Lentigo maligna presents as an irregularly pigmented macule, slowly enlarging over many years, commonly on the cheek or temple of an elderly person. It is characterized by basally located atypical melanocytes. Development of a more rapidly growing, deeply pigmented papule or nodule indicates dermal invasion by malignant melanocytes (lentigo maligna melanoma).
Acral lentiginous melanoma
Acral lentiginous melanoma is an uncommon subtype, although it is the predominant variant in the Afro-Caribbean population. The sole of the foot is most often affected and lesions may also arise on the digits. Subungual or periungual melanoma, a variant of acral lentiginous melanoma, occurs either as a linear pigmented streak in the nail or an isolated nail dystrophy, accompanied by the pigmentation of the proximal nail fold (Hutchinson's sign).
Amelanotic melanoma
Amelanotic melanoma is a non-pigmented variant of melanoma.
Malignant melanoma on mucous membranes
Malignant melanoma on mucous membranes is very rare and may affect the vulva, urethra and anus. It has a poor prognosis, due in part to its often advanced stage at presentation.
Investigations
Skin biopsy
An excision skin biopsy must be performed to confirm the diagnosis. This will give important histological data and provide valuable staging information.
Management
The management of malignant melanoma varies according to the stage at presentation, and ranges from surgical excision to radiotherapy and chemotherapy.
Prognosis
Melanoma has a mortality rate of 25% and therefore early diagnosis and treatment is essential. Prognostic factors include thickness, level of invasion, gender and site of tumor.
Histological data from melanoma
Clarke's level
I melanoma cells confined to epidermis
II melanoma cells invade papillary dermis
III melanoma cells completely occupy papillary dermis
IV melanoma cells invade mid-reticular dermis
V melanoma cells invade subcutaneous fat

Tumor thickness in mm from granular layer of the epidermis to maximum depth (Breslow thickness)
Presence of radial or vertical growth
Tumor infiltrating lymphocytes
Mitoses per mm2
Presence or absence of tumor regression (mitosis, inflammatory infiltrate, pigmentary incontinence, fibrosis and dermal scarring, and vascular proliferation)
Microsatellites
Evidence of perineural infiltrate
Evidence of vascular and lymphatic invasion
Whether excision is complete

TNM staging system for melanoma
Stage (T) Primary tumor Lymph node (N) Distant metastases (M)
0 In situ tumors No nodes No Distant metastases (M)
IA -1mm, IIB 2.01-4 mm with ulceration No nodes No Distant metastases (M)
>4 mm, no ulceration No nodes No Distant metastases (M)
IIC >4 mm with ulceration No nodes No Distant metastases (M)
IIIA Any Breslow thickness, no ulceration Micrometastases in nodes No Distant metastases (M)
IIIB Any Breslow thickness with ulceration Micrometastases in nodes No Distant metastases (M)
Any Breslow thickness, no ulceration Up to 3 palpable nodes No Distant metastases (M)
Any Breslow thickness ± ulceration No nodes but in-transit metastases or satellites None
IIIC Any Breslow thickness with ulceration Up to 3 palpable nodes No Distant metastases (M)
Any Breslow thickness ± ulceration 4 or more palpable nodes or matted nodes or in-transit metastases with nodes No Distant metastases (M)
IV M1: skin, subcutaneous or distant lymph nodes
M2: lung
M3: all other sites or any site with raised lactate dehydrogenase

Skin Mole or Nevus

Melanoma skin cancer ---> Pre skin cancer ---> skin cancer moles

Lentigo
A lentigo is a common lesion that presents as a small, pigmented macule due to an increase in the number of melanocytes within the basal layer of the epidermis. These are unaffected by sunlight. Solar lentigines develop on sun-exposed sites following either acute severe sunburn in young adults or chronic ultraviolet exposure in the elderly. Multiple lentigines may rarely be a manifestation of Peutz-Jeghers syndrome, particularly when distributed on the lips, buccal mucosa and acral sites.

Acquired melanocytic nevi
Acquired melanocytic nevi are common benign proliferations of melanocytes. They can be classified according to the site of the cluster of melanocytes. Junctional nevi describe the position of the cells at the dermal-epidermal junction above the basement membrane. Intradermal nevi describe cells that are exclusively in the dermis. Compound nevi have histological features of both junctional and intradermal nevi.
Junctional nevi present as small, dark brown, evenly pigmented, symmetrical macules. The majority of naevi in children are junctional and occur on any body site. Compound nevi (where melanocytes are present in both the epidermis and dermis) occur at any site and vary from light brown papules to dark brown papillomatous plaques. Intradermal nevi are usually detected in the third decade, frequently on the face, and may be devoid of pigment. They may be dome-shaped or pedunculated skin tags. These lesions appear in early childhood and reach a maximum in young adulthood. There is then a gradual involution, and most lesions disappear by the age of 60. A skin biopsy is only required when clinical differentiation from malignant melanoma is difficult.

Blue nevus
A blue nevus is an acquired, benign, firm, dark blue to black, sharply defined papule representing a deep dermal aggregate of melanocytes. The dermal melanocytes are thought to represent melanocytes which have failed to migrate from the neural crest to the epidermis during fetal life. Blue nevus is most common on the dorsum of hands or feet of older children and young adults. Malignant change is very rare.

Spitz nevus
A Spitz nevus is a benign melanocytic tumor that is distinct from acquired melanocytic nevi on both clinical and pathological grounds. The majority occur in children as a discrete, red-brown or pink papule on the face. The clinical presentation is distinctive and there is often a history of recent rapid growth. Differentiation from malignant melanoma may be difficult and in these cases complete excision is recommended.

Mongolian spot
A Mongolian spot is a congenital grey-blue macular lesion that can occur anywhere on the skin but is characteristically located on the lumbo-sacral area. Histologically there are ectopic melanocytes in the dermis, possibly interrupted in their migration from the neural crest to the epidermis. Mongolian spots disappear in early childhood. No melanomas have been reported in these lesions.

Nevus spilus
A nevus spilus is a common lesion consisting of a light brown macule, varying in size from a few centimeters to a very large area, with many darker small macules (2-3 mm) or papules scattered throughout. Histologically, the background macule shows an increased number of melanocytes and the scattered lesions are either junctional or compound nevi. Malignant melanoma very rarely arises in these lesions.

Dysplastic melanocytic nevus
Dysplastic melanocytic nevi are melanocytic lesions with atypical clinical and histological features. They are regarded as potential precursors of superficial spreading melanoma and also as markers of persons at risk for developing primary malignant melanoma. These pigmented lesions are clinically distinct from acquired melanocytic nevi, being larger and more variegated in color, with an asymmetrical outline and irregular border. Lesions may occur sporadically or may arise against a background of dysplastic nevus syndrome, an autosomal dominant condition with multiple atypical nevi. Surgical excision of lesions with minimal margins is recommended, especially in lesions that are changing or those that cannot be closely followed by the patient (on the scalp or back).

CLINICAL ALERT
Six signs of malignant melanoma
A
Asymmetry in shape
B
Border is irregular
C
Color variation-shades of brown, black, grey, red and white
D
Diameter is usually large, >6 mm
E
Elevation is almost always present

Malignant Melanoma pictures

skin cancer pictures ---> melanoma skin cancer ---> melanoma pictures.

Causes of Melanoma

Melanoma skin cancer ---> Causes of melanoma

Numerous environmental and genetic risk factors have been implicated in the development of cutaneous melanoma. Risk factors include ultraviolet light (UVL) exposure, fair complexion/inability to tan, blue or green eyes, blonde or red hair, freckling, history of actinic keratosis or nonmelanoma skin cancer, history of blistering or peeling sunburns, immunosuppression, personal or family history of melanoma, xeroderma pigmentosa, atypical (dysplastic) nevus, more than 100 normal nevi, and giant congenital melanocytic nevus. Patients with a significant history of sun exposure are at particularly high risk, especially if they experienced peeling or blistering sunburns, even during childhood. Melanoma occurs infrequently in skin of color, suggesting that skin pigment plays a protective role. Melanoma incidence is subject to large geographic and ethnic variations, mainly because of an inverse correlation with latitude and with degree of skin pigmentation. Populations residing closer to the equator have a higher incidence of melanoma. Certainly UVL exposure from sun or artificial light sources is considered the best-known risk factor. However, UVL exposure does not cause all or even most melanomas.
Adults with more than 100 clinically normal-appearing nevi, children with more than 50 clinically normal-appearing nevi, and any patient with atypical or dysplastic nevi are at risk. A prior history of melanoma places a patient at increased risk, with 5% to 10% of individuals developing a second primary melanoma. This risk of developing a second primary is lifelong and can occur anywhere on the skin. Therefore, long-term surveillance with a thorough total body examination is recommended.
A genetic component has been implicated in the pathogenesis of melanoma. Of patients with melanoma, 10% to 15% report a positive family history. The genetic etiology of melanoma represents an area of future discovery.
The hereditary nature of cutaneous melanoma was also noted in the 1970s. Members afflicted with the B-K mole syndrome, named after two families, acquired large, irregular, and dysplastic nevi, often in sun-protected regions of the body such as the scalp and trunk. Familial association of melanoma among individuals with atypical nevi, is termed Familial Atypical Multiple Mole-Melanoma Syndrome, or FAMMM syndrome, with an autosomal dominant inheritance pattern. An atypical nevus is not a pre melanoma but represents a genetic marker for increased risk of development of melanoma, which may occur anywhere on the skin surface including sun-protected sites. In fact more than 50% to 75% of melanomas develop on clinically normal skin de novo, not in preexisting melanocytic lesions.
Xeroderma pigmentosa (XP) is a rare autosomal recessive disorder associated with a reduced or absent ability to repair DNA damaged by ultraviolet light. Consequently, this disorder results in the development of multiple primary cutaneous malignancies, including melanoma as well as BCC and SCC. Individuals are usually diagnosed with their first cancer before the age of 10 years. Unfortunately, the development of skin cancers is relentless.
Congenital melanocytic nevi (CMN) are present at birth or appear within the first 6 months of infancy. An estimated 1% to 6% of children are born with CMN. The nevi are classified by size. Small CMN measure less than 1.5 cm in diameter and account for the majority of lesions. Medium CMN measure between 1.5 and 19.9 cm in diameter. Large CMN, also termed giant congenital nevi, measure 20 cm or greater. This large size can lead to significant cosmetic and psychosocial implications. The risk of melanoma development in small and medium-size CMN is similar to any other area of skin. Melanoma development in small and medium CMN usually occurs after childhood and arises from the dermoepidermal junction, making early detection feasible. Routine prophylactic removal of small and medium CMN is rarely indicated in the absence of signs or symptoms for malignant progression. Conversely, giant congenital nevi carry an increased risk for melanoma, with an estimated rate of 5% to 20%. Of giant congenital nevi that progress to melanoma, 70% are diagnosed prior to age 10 years. Melanoma can originate deep in the epidermis in giant congenital nevi. Consequently, diagnosis within the setting of giant congenital nevi is challenging and may develop deep in the skin with a more advanced primary lesion.

Metastatic Workup for Melanoma

Melanoma skin cancer ---> metastatic melanoma ---> diagnosis of melanoma

In an attempt to standardize staging workup for melanoma, the National Comprehensive Cancer Network (NCCN) has published guidelines. There are three basic reasons to perform a metastatic workup following the diagnosis of primary cutaneous melanoma: (a) for staging and prognosis, (b) to detect an early metastasis with potential survival benefit, and (c) to avoid morbidity of an extensive surgical procedure by detection of a distant metastasis. The best test for the staging workup still starts with a history (focused review of systems concentrating on constitutional, respiratory, neurologic, hepatic, musculoskeletal, gastrointestinal, skin, and lymphatic systems) and physical examination (total body skin examination, palpation of lymph nodes). Routine imaging and blood studies in asymptomatic patients are low in both sensitivity and specificity. False-positive staging tests are common and lead to more tests and patient distress. SLNB represents the best baseline staging test, with both relatively high sensitivity and specificity in patients at significant risk for metastasis. The ability to detect stage IV disease with routine studies is small if the SLNB is negative. Ultrasound is perhaps the most sensitive noninvasive test to detect small nodal metastases. However, the sensitivity and specificity of ultrasound and PET scanning are inferior to tissue diagnosis with SLNB.

Evaluation for Metastatic Melanoma

Melanoma skin cancer ---> metastatic melanoma ---> diagnosis of melanoma

The follow-up evaluation for patients with AJCC stage I, II, or III melanoma who are rendered tumor free by surgery should include regular histories and physical examinations. The use of extensive and frequent radiographic studies and blood work in asymptomatic, clinically disease-free patients is rarely productive. In 2004, the National Comprehensive Cancer Network issued guidelines for follow-up of patients with various stages of disease. For AJCC stage IA, patients should undergo a history and physical examination with emphasis on skin and nodal examinations every 3 to 12 months as clinically indicated. For AJCC stage IB to III, patients should undergo a history and physical examination every 3 to 6 months for 3 years, then every 4 to 12 months for 2 years, then annually as clinically indicated. The use of chest radiographs and blood work, and other imaging scans are indicated when clinically indicated, is based on the history and physical examination.
Melanoma can disseminate to any organ. The most common sites of recurrence are skin, subcutaneous tissues, and distant lymph nodes, followed by visceral sites. Common visceral sites of metastasis, in order of decreasing occurrence, are lung, liver, brain, bone, and gastrointestinal tract. Most patients who die with disseminated disease have multiple organ involvement. Frequently, the cause of death is respiratory failure or brain complications. Patients with disseminated disease have a poor prognosis, with a mean survival of approximately 6 months. Cure with any treatment is rare. Selection of treatment or a decision against treatment should be based on several factors, including the patient's medical condition, the potential for palliation, and the impact of treatment on quality of life.

Surgical Excision of Primary Melanoma

Melanoma skin cancer ---> primary melanoma ---> melanoma treatment ---> melanoma surgery

The primary purpose of a melanoma excision is to prevent local recurrence due to persistent disease. For melanoma in situ, excision margins of 0.5 to 1 cm are indicated. For invasive melanoma, wide excision of the primary tumor, with margins generally ranging from 1 to 2 cm, is indicated for local control. The optimal margin width remains somewhat controversial. The historical approach of excising all primary melanomas with a 3- to 5-cm margin is extinct. At least five randomized controlled trials failed to demonstrate a difference in overall survival or local recurrence with narrow (1 to 2 cm) versus wide (3 to 5 cm) margins. Of note, one trial demonstrated an increased risk of locoregional recurrence with 1 versus 3 cm margins for melanoma more than 2 mm thick.25 Hopefully, results from future randomized prospective trials will demonstrate how narrow a margin is truly safe and efficacious. Until more definitive data become available, current consensus guidelines recommend margins of 1 cm for melanoma of 1 mm or less thick, 1 to 2 cm for 1 to 2 mm thick, and at least 2 cm for greater than 2 mm thick.

Treatment of Regional Metastatic Melanoma

Melanoma skin cancer ---> metastatic melanoma ---> regional metastasis---> melanoma treatment

Surgical excision of metastases to regional lymph nodes is potentially curative therapy. The 5-year survival rate for patients who undergo lymphadenectomy for clinically positive involved nodes (AJCC stage III) ranges from 25% to 70%. In addition, for those patients not cured by lymphadenectomy, resection can avoid potential pain associated with tumor enlargement, skin breakdown, and tumor necrosis. Only 10% of patients who first present with the diagnosis of melanoma have clinical evidence of nodal metastases; approximately 85% have localized disease; the remaining 5% have distant metastases. In less than 3% of patients, a diagnosis of melanoma is made in the absence of a definable primary lesion.28 When patients present with isolated nodal disease from an unknown primary site, the results of lymphadenectomy are similar to those for patients with known primary tumors. For patients with melanoma 1.0 mm thick or greater who present with clinically negative nodes, SLNB should be considered to determine whether therapeutic lymphadenectomy is indicated.

Surgery for Metastatic Melanoma

Melanoma skin cancer ---> metastatic melanoma ---> melanoma treatment ---> melanoma surgery

Surgical excision of recurrent melanoma can be effective for palliation in patients with isolated recurrences in the skin, central nervous system, lung, or gastrointestinal tract. Surgical excision of solitary brain metastases has been shown to provide improved palliation and quality of life compared with brain irradiation. Resection of isolated pulmonary metastases or of subcutaneous recurrences is usually not considered curative but can result in significantly prolonged disease-free survival. Gastrointestinal lesions causing obstruction or bleeding should be considered for resection or bypass to relieve these symptoms.

Chemotherapy for Melanoma

Melanoma skin cancer ---> melanoma treatment ---> melanoma chemotherapy

Melanoma is responsive to few chemotherapeutic drugs. The best single agents for treatment of melanoma are DTIC, the nitrosoureas, vinca alkaloids, and cisplatin, which have objective response rates in the range of 10% to 20%. Conventionally, objective responses have included complete disappearance of all known tumor sites (complete response) and reduction of more than half in all assessable tumor (partial response). Complete responses are rare and nearly always of brief duration (<6months).
Radiation Therapy
Melanoma can respond to radiation therapy. Radiation therapy is commonly used for palliation of bone pain secondary to metastatic disease or brain metastasis. The average survival after brain irradiation for melanoma is approximately 4 months.

Immunotherapy for Melanoma

Melanoma skin cancer ---> melanoma treatment ---> melanoma immunotherapy

The rapid evolution of recombinant DNA technology has resulted in the availability of cytokines, such as the interferons and interleukins, that can be administered to modulate a patient's immune response. These biologic agents have been used in immunotherapeutic trials for metastatic melanoma and demonstrate that an anti-tumor immune response can be generated in selected patients.
The most significant advance in melanoma immunotherapy has been associated with the use of interleukin-2 (IL-2). IL-2 is a cytokine secreted by antigen-activated helper T cells and was initially discovered because it was a T-cell growth factor. Subsequently, it was found to have many other immunologic effects, and it appears to have an important role in the enhancement of immune responses. It has been discovered that the in vivo administration of IL-2 in preclinical animal models resulted in dramatic tumor regression. In clinical studies, the administration of IL-2 resulted in a 15% to 20% response rate in patients with advanced melanoma. Approximately 5% of patients have a complete response which has been durable for prolonged periods. This latter result prompted the FDA to approve IL-2 for the treatment of metastatic melanoma.
IL-2 has been used in combination with other forms of immunotherapy. One example of this is the use of anti-tumor reactive T cells as reagents to treat tumor that is called adoptive immunotherapy. One source of these T cells is from the tumor itself, known as tumor-infiltrating lymphocytes. It has been reported that patients with advanced melanoma treated with the combination of tumor-infiltrating lymphocytes, IL-2, and chemotherapy can result in response rates between 35% and 50%.
Vaccines derived from melanoma tumor cells or extracts of tumor cells have been an emerging field in the treatment of melanoma. The discovery of unique melanoma tumor associated antigens has opened the door for the development of highly specific reagents for tumor vaccines.

Biochemotherapy for Melanoma

Melanoma skin cancer ---> melanoma treatment ---> melanoma biochemotherapy

Combinations of IL-2 and/or IFN- with chemotherapy, known as biochemotherapy, have shown significant improved response rates compared with chemotherapy alone or cytokines alone. As might be expected, these regimens are more toxic than the component therapies by themselves. One of the biochemotherapy regimens that has demonstrated a significant response rate (i.e., 64%, including 21% complete and 43% partial) with moderate toxicity is a combination of cisplatin, vinblastine, dacarbazine, IL-2, and IFN- . A follow-up randomized trial comparing this biochemotherapy regimen to chemotherapy alone indicated that the addition of the cytokines significantly enhanced the anti-tumor activity of the chemotherapy. Biochemotherapy should be considered in patients with advanced melanoma who are thought to be able to tolerate the toxicities of the therapy.

Gene Therapy for Melanoma

Melanoma skin cancer ---> melanoma treatment ---> melanoma gene therapy

The technical feasibility of transfer of genetic material into somatic cells has established a new approach to the treatment of malignancies. Many of the gene therapy strategies for cancer have focused on modulating the host immune response by altering tumor cells to be more immunogenic. A variety of preclinical studies have demonstrated that genetic engineering of tumor cells to secrete or express immunoregulatory peptides (i.e., cytokines, costimulatory molecules, or adhesion molecules) increases the host immune response to these tumors Several clinical studies are evaluating the efficacy of genetic modification of melanoma tumor cells to secrete cytokines that can be administered to patients as tumor vaccines.

Melanoma staging and survival

melanoma skin cancer ---> melanoma survival


A great deal of information is available regarding various factors that correlate with the clinical outcome of patients with melanoma. Some of these prognostic factors, such as microstaging and nodal status, are of sufficient independent significance to be incorporated into staging systems with known survival rates. Other prognostic factors, such as tumor ulceration and microscopic versus macroscopic nodal disease, have also been found to be significant variables that influence survival and have been incorporated into the staging system.

One of the most important prognostic features of cutaneous melanoma is the stage of development of the primary tumor. The microstaging method that is used routinely was originally described by Breslow. This method classifies the primary tumor according to its thickness in millimeters, as measured with an ocular micrometer, from the top of the granular layer to the base of the tumor. Many investigators have documented an inverse correlation between tumor thickness and survival. The ulceration status and mitotic rate are also independent factors that are used to determine microstaging of the primary lesion. Prior to the use of the Breslow microstaging method, melanomas were staged according to the level of invasion into the histologic layer of skin. This was known as Clark's level of invasion and comprised five levels (I = in situ lesions, V = subcutaneous involvement). Several studies have confirmed that Breslow thickness conveys more accurate prognostic information than does the determination of Clark level.
The presence of regional lymph node metastases is associated with a worsening prognosis. The tumor burden (microscopic versus macroscopic disease) of involved lymph nodes has an inverse correlation with long-term survival. The 5-year survival rate for patients with involved lymph nodes ranges from 70% to 25%, based primarily on tumor burden and ulceration status of the primary lesion). The use of sentinel lymph node biopsy (SLNB) has identified a subgroup of patients with micrometastatic nodal disease who have a favorable prognosis compared with patients with macroscopic nodal involvement. This information has been incorporated in the staging system as well.

The American Joint Committee on Cancer (AJCC) developed a five-stage system that divides melanomas according to tumor thickness (T), nodal status (N), and metastatic disease (M). There are five stages based on prognosis: stage 0 (in situ melanoma), stage I (local disease), stage II (local disease), stage III (regional nodal, in-transit, or satellite metastases), and stage IV (distant metastases). In general, increasing stage is associated with decreasing survival.

The major prognostic factors that predict survival in melanoma patients have been accounted for in the AJCC staging system: namely, tumor microstaging, ulceration, nodal status, and distant metastases.The presence of ulceration in a melanoma appears to be associated with a poorer prognosis. Men have a higher proportion of ulcerated lesions than women (27% vs. 19%, respectively). Although ulceration appears to correlate with thickness of the melanoma, the presence of ulceration has been shown to be an independent prognostic factor and has been included in the staging system. Additionally, a higher mitotic rate of 1.0 mm2 or greater has been shown to be an independent prognostic factor in one large study.

How to Identify Skin Cancer Signs : What Causes Melanoma Skin Cancer?

Skin cancer awareness ---> skin cancer videos ---> melanoma skin cancer ---> Causes of melanoma

Learn what causes melanoma skin cancer with expert tips from a doctor on skin health.

How to Identify Skin Cancer Signs : Signs of Melanoma Carcinoma Skin Cancer

Skin cancer awareness ---> skin cancer videos ---> melanoma skin cancer ---> Skin cancer detection ---> signs of melanoma

Learn how to recognize the signs of melanoma carcinoma skin cancer with expert tips from a doctor on skin health.

Identifying Melanoma (Health Tip)

Skin cancer awareness ---> skin cancer videos ---> melanoma skin cancer ---> Skin cancer detection


Is that a beauty mark....or a cancerous growth? While the former is likely, it's good to be aware of the latter!

Treating Melanoma

Skin cancer awareness ---> skin cancer videos ---> melanoma skin cancer ---> melanoma treatment


If left untreated, melanoma can be fatal. Luckily, there are a host of options that can prevent this.

Understanding Melanoma

Skin cancer awareness ---> skin cancer videos ---> melanoma skin cancer ---> melanoma information

Melanoma is the most rare—and the most serious—type of skin cancer. Learn more about melanoma.

Surviving Melanoma

Skin cancer awareness ---> skin cancer videos ---> melanoma skin cancer ---> melanoma survival


Just when you think you have problems you hear a story like this.