Childhood Melanoma Bhaskar N. Rao, MD Department of Surgery March 3, 2006 St. Jude Children’s Research Hospital

☼ Childhood Melanoma Is pediatric melanoma different from adult melanoma?

☼ Childhood Melanoma Most virulent of skin malignancies Estimated 26,000 new cases in 1996 Represents 1-3% of all malignancies Less than 1% in children 300 / yr) Second to Thyroid cancer (Adult)

☼ Childhood Melanoma Adult vs. Pediatric Similar sex distribution Similar anatomic location Thicker lesions Prognosis is stage dependent

☼ Childhood Melanoma Reported Series 588 patients caucasians 80% second decade of life Extremity most common site 75% localized disease Predisposing conditions in 20% Nodular melanoma in 50% Prognosis is stage dependent

☼ Childhood Melanoma St Jude Experience Over 2/3 of children presented with intermediate to thick melanomas (> 1.5 mm) Incidence of nodal disease vary with depth of invasion

☼ Childhood Melanoma Risk Factors Giant congenital nevi 2-3% Xeroderma pigmentosa22-57% skin cancers ImmunodefficiencyHodgkins disease 8 fold Other (HIV / Transplant) 4 to 8 fold Radiation therapy 44% of melanoma occur in nevi present at birth Neurocutaneous melanosis

☼ Childhood Melanoma

Copyright restrictions may apply. ABCDE Features of Cutaneous Melanoma Abbasi, N. R. et al. JAMA 2004;292: Asymmetry - Focal growth - Ulceration - Tenderness - Dark pigmentation - Pruritis - Bleeding Evolving Color VariegationDiameter > 6 mm Border Irregularity

☼ Childhood Melanoma

☼ Childhood Melanoma Histologic Parameters of Prognostic Significance Clark’s level of Invasion: Difficult to reproduce Breslow’s thickness: Measured from granular layer of epidermis to greatest depth of invasion Ulceration Mitotic rate Vascular invasion Lymphatic infiltration

☼ Childhood Melanoma Mole phenotype 1% of newborns have nevi 15% of patients will say nevi were at the site of melanoma MM assoc with cong. nevi occurs before puberty Role of solar exposure Dysplastic nevi in 5-10% are larger than 5 mm (familial / non familial) risk of MM 5-10% Germline mutations

☼ Childhood Melanoma Congenital Nevi May develop in utero in absence of maternal melanoma Fetus from Giant mel nevus or denovo Transplacental transmission (46%) Latter have disseminated disease

☼ Childhood Melanoma Giant Pigmented Nevi Size of palm (face) or twice elsewhere Surgery and primary closure not feasible Dark brown / black and Irregular surface / margins Many have coarse terminal hairs Melanoma risks 2-30% (Mean 12%) a.) Staged excision Surgeryb.) Tissue expanders c.) Tissue culture d.) dermabrasion

Incidence –~1 in 500,000 newborns –Appearance Pigmented Hairy Cerebriform appearance (corrugated) Nodular ☼ Childhood Melanoma Giant/Large CMN

–Natural history Expands with growth Change in color, topography Surface pigment may fade with time Hair growth Limb discrepency –Associations Scoliosis, spina bifida, clubfoot ☼ Childhood Melanoma Giant/Large CMN

Malignant transformation –Cutaneous and non-cutaneous –Melanoma is most common, but also Rhabdomyosarcoma, neuroblastoma, liposarcoma, MPNST, neurofibroma –Presenting symptoms ☼ Childhood Melanoma Giant/Large CMN

☼ Childhood Melanoma Dysplastic Nevus Variety of compound nevus seen in Familial Dysplastic Nevus Syndrome Large number irregularly bordered nevi Commonly seen on the back Usually greater than 5 mm with irregular pigmentation and margins Lifetime risk approx. 10%

☼ Childhood Melanoma Dysplastic Nevus

☼ Childhood Melanoma Management of Dysplastic Nevus Syndrome Thorough exam and photography Patient education Regular follow-up Screen first degree relatives over the age of ten Excisional biopsy of representative suspicious lesions (scalp and difficult areas

☼ Childhood Melanoma Xeroderma Pigmentosa Autosomal recessive, photosensitivity, > 1000 fold of skin ca Results from defect - XPA - XPG - XPV Malignant skin ca develops in 70% (median 8 yrs) 57% Squamous or Basal cell 22% melanomas Majority head and neck and exposed areas Prevent sunlight exposure, clothing, sunscreens (preventative)

Incidence –Rare –Non-familial –females = males –~100 cases described Risk factors –Satellite nevi (> 10) –Cutaneous nevus in midline overlying the trunk or calvarium ☼ Childhood Melanoma Neurocutaneous Melanosis (NCM)

Prognosis –Symptomatic – death within 2-3 years from dx –Asymptomatic – lifetime risk of CNS melanoma = cutaneous melanoma Treatment –Supportive –No effective treatment ☼ Childhood Melanoma Neurocutaneous Melanosis (NCM)

Surgical resection of primary tumor <1mm thick and no ulceration and no Clark level IV or V Adequate margins (1cm) Follow clinically 1mm Sentinel LN biopsy + - WLE (2 cm margin), LN Dissection and Metastatic w/u WLE (2 cm margin) Consider interferon therapy - Stage III Stage Ib/II Stage Ia Follow clinically or consider clinical trial + 1.Clinical trial 2.IL-2 3.DTIC or TMZ 4.Biochemotherapy Stage IV ☼ Childhood Melanoma Management

☼ Childhood Melanoma SurgicalManagement Suspicious lesionExcisional biopsy InsituSimple excision <1 mm1 cm margin 1-4 mm2 cm margin Two thirds (> 1.5 mm) have nodal involvement Do MRI, lymphoscintigraphy and sentinel node biopsy

☼ Childhood Melanoma SurgicalManagement

☼ Childhood Melanoma Role of Pediatrician and Surgeon P revention A wareness R ecognition R esearch