• Melanoma

• Pathophysiology:
• Epidermis consists of four layers (deep to superficial) – stratum basale, spinosum, granulosum, and corneum
• Melanocytes are present in the stratum basale layer, and this is where melanoma arises (question on last year’s inservice)
• Risk factors:
• UV exposure, Age (50% occur in patients older than 50 years), prior skin cancer diagnosis, family history
• More common in males (seen on trunk and head) compared to females (lower extremity)
• Fitzpatrick skin type I and II are at highest risk, as well as those with lighter hair color
• Predisposing Conditions:
• Typical moles – increased risk of >50 moles present
• Dysplastic Nevus – atypical melanocytes with transformation potential, 6-10% risk of malignant degeneration
• Atypical Mole Syndrome (Familial atypical multiple-mole melanoma or FAMMM) – More than 100 melanocytic nevi, one or more measuring >8mm, one or more with clinically atypical features
• 10% risk of melanoma 
• Melanoma Growth Pattern:
• Superficial Spreading
• Most common 50-70% of cases, arises from preexisting nevus 
• Long HORIZONTAL growth phase
• Nodular
• Aggressive subtype that makes up 15-30% of all cases, increased incidence in men
• Arises de novo in normal skin
• Lentigo Maligna Melanoma
• Also called “Hutchinson’s Freckle”
• Technically considered a precancerous lesions and should be excised with 1cm margins due to low malignant potential
• Acral-Lentiginous Melanoma
• Found on the palms and soles, more common in nonwhite patients
• May present with melanonychia (linear pigmented streak in the nail)

• Benign juvenile melanoma: (spitz nevus, spindle cell nevus, epitheloid nevus)
• Pink/red lesion that appears on face, shows giant spindle cells, complete excision recommended

• Subungual Melanoma

• Risk Factors: age >50, width greater than 3mm, change in color over time, pigmentation of periungual skin
• Common question is how to differentiate subungual hematoma with melanoma
• Hematoma –pigmented area will migrate distally over 3-4wks, whereas melanoma will not
• “Hutchinson’s nail sign” – extension of brown/black pigment from nailbed and matrix and nail plate to the adjacent cuticle and proximal or lateral nail folds
• May indicate melanoma

• Diagnosis
• Full thickness biopsy of nailbed 
• Treatment:
• Surgical management of these lesions is controversial, but in general treatment will be based on depth of the lesion
• Melanotic hyperplasia may be observed, Melanoma in situ or melanotic dysplasia can be treated with wide local excision alone, while more advanced disease may require amputation 

• Melanoma Staging:
• Breslow Thickness (depth in mm) and Clark’s level (histologic invasion through skin layers)
• Breslow thickness is MOST IMPORTANT prognostic variable
• Breslow grading system:
• Grade 1: 0-0.75mm
• 2: 0.76-1.5mm
• 3: 1.51-4mm
• 4: >4mm
• If excision upgrades breslow no need to re-excise especially If < 2mm
• SLNB – indicated in melanomas >0.8mm thickness and if there is ulceration 
• Immunohistochemical markers: s-100, HMB-45, MART-1
• If patient has visceral mets (other than lung)àbad prognosis
• Elevated LDHà also bad prognosis
• Treatment:
• Excision

• Depth – TO level of fascia (but not including the fascia)
• Special considerations:
• Lentigo maligna *aka hutchinsons freckle*
• 1cm margins
• SLNB
• STAGING procedure, not therapeutic
• Indications > 0.8mm in depth or if lesion is ulcerated

Special considerations:

• Lentigo maligna *aka hutchinsons freckle*
• 1cm margins for excision
• OTHER OPTIONS – topical imiquimod (immune response modifying agent) is an alternative to surgical excision in poor surgical candidates or patients who refuse surgical intervention 

• Adjuvant Therapy
• Guided by our surgical oncology colleagues 
• May involve interferon, radiation therapy, chemotherapy, or immunotherapy

• Miscellaneous: 

• For pregnant patients, resection should be completed with local if within 1st trimester
• 2nd trimester may undergo general anesthesia for SLNB

• Congenital Melanocytic Nevus – 

• Pathophysiology involves the disruption of normal growth, development, and migration of melanoblasts which migrate from neural crest to various parts of the body
• “Giant” CMN is >20cm
• Overall risk of melanoma in this population is <3%, compared to 0.6% in the general population
• Surgical treatment of giant CMN does NOT reduce risk of melanoma,