OBJECTIVES:

Primary

• Study the natural history of large congenital melanocytic nevi (LCMN), acquired melanocytic nevi, and clinically suspicious pigmented lesions through a tissue acquisition protocol.
• Obtain tissue from benign melanocytic nevi and LCMN for experimental study.
• Refine culture and immortalization methods for melanocytes derived from melanocytic nevi that permits in vitro expansion of these cells for functional study.
• Correlate clinical and dermoscopic observations of primary melanoma with histopathology to establish standards for sampling primary melanoma in a possible future study.

Secondary

• Obtain, prospectively, a set of tissue samples of melanocytic nevi and primary melanoma with detailed clinical information for evaluating novel diagnostic techniques and for the basis of a nevus/primary melanoma tissue microarray.

OUTLINE: Patients are stratified according to diagnosis (children ≤ 5 years of age with large congenital melanocytic nevi vs adults with ≥ 100 acquired melanocytic nevi vs adults with suspected primary melanoma).

Patients undergo extensive full-body photography to document the number, type, and location of melanocytic nevi and pigmented lesions. Patients will also undergo excisional or staged (incisional and excisional) biopsy* of the melanocytic nevi or pigmented lesions. Dermoscopic images are performed before and after biopsy* on both clinically benign melanocytic nevi and pigmented lesions that are clinically suspicious for primary melanoma. Patients with a diagnosis of malignant melanoma receive standard care for primary melanoma.

NOTE: *Patients with lesions < 4 mm OR lesions 4-6 mm with ≤ 1-axis symmetry do not undergo biopsy.

Biopsy tissue will be used for immortalization of nevus-derived melanocytes and mutation screening (e.g., somatic mutations at codon 599 of BRAF and codon 61 of NRAS) and functional studies (e.g., gene expression analysis) of nevus-derived melanocytes.

Patients diagnosed with malignant melanoma and < 100 acquired melanocytic nevi are followed every 6 months for ≥ 2 years and then annually for ≥ 3 years. All other patients are followed every 6 months.

PROJECTED ACCRUAL: A total of 110 patients will be accrued for this study.

DISEASE CHARACTERISTICS:

• Meets 1 of the following criteria:

  • Children ≤ 5 years of age meeting the following criteria:

    • Histologically confirmed or clinically diagnosed large congenital melanocytic nevi

      • Must be > 20 cm in any 1 dimension OR > 8 cm in any 1 dimension involving the scalp

  • Adults > 18 years of age meeting 1 of the following criteria:

    • Must have ≥ 100 melanocytic nevi > 2 mm in diameter AND ≥ 1 melanocytic nevus ≥ 4 mm in longest dimension

      • Prior history of cutaneous or ocular malignant melanoma allowed
    • Pigmented lesion clinically suspicious for primary melanoma
• No genetic syndrome associated with multiple lentigines or nevi (e.g., Peutz-Jeghers syndrome, Carney complex, Turner syndrome, or Noonan's syndrome)
• No more than 1 first-degree relative with a history of cutaneous melanoma and familial atypical mole-melanoma syndrome phenotype
• No cancer-associated syndrome (e.g., xeroderma pigmentosum, type 1 neurofibromatosis, or Li-Fraumeni syndrome)
• No metastatic melanoma

PATIENT CHARACTERISTICS:

• Must have outside primary physician
• Able to tolerate surgical procedure
• No bleeding diathesis, coagulopathy, or excessive bleeding tendency

PRIOR CONCURRENT THERAPY:

• No recent chemotherapy