Melanoma: Early Detection and Treatment Guide

What is Melanoma?

Melanoma is a malignant tumor of melanocytes (pigment-producing cells) with capacity for rapid metastatic spread. While comprising only 5% of skin cancers, melanoma accounts for 80% of skin cancer deaths. Five-year survival rates vary dramatically by stage: stage 1A (localized, <1mm) shows 99% survival; stage 4 (metastatic) shows <10% survival. Early detection and treatment are critical for favorable outcomes. Incidence continues rising globally, projected to increase 3-7% annually over next 20 years.

Epidemiology

Approximately 100,000 melanomas diagnosed annually in the United States; rates are highest in Australia (40/100,000) due to high sun exposure and fair population. Peak incidence occurs ages 40-60 though can develop at any age. Higher prevalence in fair-skinned populations; rates increasing in dark-skinned individuals with higher mortality due to later stage diagnosis. Gender distribution roughly equal with slight male predominance.

Risk Factors

Solar UV Exposure: Primary risk factor; intermittent intense exposures and sunburns (especially childhood) significantly increase risk. Fair Phenotype: Fitzpatrick I-II skin 20-40 fold higher risk than dark skin. Atypical Nevi: Dysplastic nevus syndrome confers 500-fold increased risk. Family History: 10% of patients have affected relatives; CDKN2A mutations increase familial risk. Immunosuppression: 20-40 fold increased risk in transplant recipients. Previous Melanoma: 1-5% risk of second primary melanoma.

ABCDE Detection Criteria

Asymmetry: One half unlike the other. Border: Irregular, scalloped, or notched edges. Color: Variation within lesion (brown, black, tan, red, blue, pink, white). Diameter: >6mm (pencil eraser size), though melanomas can be smaller. Evolving: Changing in size, shape, color, or symptoms (bleeding, itching, pain). Any concerning feature warrants dermatological evaluation.

Types of Melanoma

Superficial Spreading Melanoma

Most common (70%); typically <1mm at presentation. Irregular border and color variation typical. Often arises within dysplastic nevus. Slow initial growth in radial phase; risk increases when vertical (deep) growth phase begins.

Nodular Melanoma

15-20% of melanomas; presents as dark nodule/papule. More aggressive; rapid vertical growth common. Earlier dermal invasion increases depth at diagnosis and mortality risk.

Lentigo Maligna Melanoma

10% of melanomas; arises from lentigo maligna (melanoma in situ) on chronically sun-exposed skin (face, ears) in elderly patients. Often >2cm at presentation but slow growth and limited depth at diagnosis typically associated with favorable prognosis.

Acral Lentiginous Melanoma

2-10% of melanomas but 30-40% of melanomas in dark-skinned individuals. Located on palms, soles, nail beds. Often diagnosed at advanced stage. Higher mortality despite aggressive treatment.

Staging and Prognosis

Stage 1A: Localized <1mm thickness; 99% 5-year survival. Stage 1B: 1-2mm thickness; 97% 5-year survival. Stage 2: 2-4mm thickness or ulceration/high mitotic rate; 90% 5-year survival. Stage 3: Regional lymph node involvement; 50-70% 5-year survival depending on number of nodes. Stage 4: Distant metastases; <10% 5-year survival. Breslow thickness (measured in millimeters from surface to deepest cell) is single most important prognostic factor. Ulceration, high mitotic rate, and deep margins worsen prognosis at any thickness.

Diagnostic Procedures

Dermoscopy: Handheld magnification tool revealing subsurface structures and patterns. Diagnostic algorithms identify melanoma with 90%+ sensitivity/specificity. Biopsy: Definitive diagnosis; excisional biopsy with narrow margins preferred for suspected melanomas. Sentinel Node Biopsy: For melanomas >1mm, identifies lymph node metastases (present in 20% of stage 1B-2 patients) guiding staging and treatment decisions. Imaging: CT, MRI, or PET scanning for stage 3-4 disease to assess distant metastases.

Treatment Options

Surgical Treatment

Excision: Definitive treatment for localized melanoma. Margins depend on thickness: <1mm requires 1cm margins; 1-4mm requires 1-2cm margins; >4mm requires 2cm margins. Wide local excision with adequate margins minimizes recurrence. Lymphadenectomy: Regional lymph node dissection recommended if sentinel node positive or clinical evidence of metastatic disease.

Systemic Therapy

Immunotherapy: Checkpoint inhibitors (nivolumab, pembrolizumab, ipilimumab) activate T-cell immunity against melanoma. Superior to traditional chemotherapy with durable responses in 40-50% of patients. Adverse autoimmune events occur in 20-30%; typically manageable with treatment discontinuation and corticosteroids. Targeted Therapy: BRAF/MEK inhibitors (vemurafenib, dabrafenib + trametinib) for BRAF V600-mutated melanomas (45% of cases). Response rates 50-70% but rapid resistance development typical within months.

Radiation

Adjuvant radiation for high-risk resected disease or unresectable disease. Palliative radiation for brain metastases or bone involvement.

Post-Treatment Follow-up

Stage 1A patients require annual skin examination and self-examination. Stage 1B-2 requires examination every 3-6 months for 3 years, then annually. Advanced stage requires more frequent assessments and imaging surveillance. Patient education on self-examination is critical as 15-20% of melanoma recurrences are self-detected. Psychological support for advanced melanoma important as prognosis initially was poor; recent therapies have dramatically improved outcomes for advanced disease.