Melanoma/Skin Cancer Health Center

Note: Some citations in the text of this section are followed by a level of evidence. The PDQ editorial boards use a formal ranking system to help the reader judge the strength of evidence linked to the reported results of a therapeutic strategy. (Refer to the PDQ summary on Levels of Evidence for more information.)

Stage I melanoma is defined by the American Joint Committee on Cancer's TNM classification system:[1]

• T1a, N0, M0
• T1b, N0, M0
• T2a, N0, M0

Standard Treatment Options for Patients With Stage I Melanoma

Standard treatment options for patients with stage I melanoma include the following:

• Current evidence suggests that lesions 2 mm or less in thickness may be treated conservatively with radial excision margins of 1 cm. A randomized trial compared narrow margins (1 cm) with wide margins (at least 3 cm) in patients with melanomas no thicker than 2 mm.[2,3] No difference was observed between the two groups in respect to the development of metastatic disease, disease-free survival (DFS), or overall survival (OS). Two other randomized trials have compared 2 cm margins with wider margins (i.e., 4 cm or 5 cm), and found no statistically significant difference in local recurrence, distant metastasis, or OS, with a median follow-up of 10 years or more for both trials.[4,5,6][Level of evidence:1iiA] In the Intergroup Melanoma Surgical Trial, the reduction in margins from 4 cm to 2 cm was associated with a statistically significant reduction in the need for skin grafting (from 46% to 11%, P < .001) and a reduction in the length of the hospital stay.[6] Depending on the location of the melanoma, most patients can now have this procedure performed on an outpatient basis.

  Elective regional lymph node dissection is of no proven benefit for patients with stage I melanoma. Lymphatic mapping and sentinel lymph node (SNL) biopsy for patients who have tumors of intermediate thickness and/or ulcerated tumors, however, may allow the identification of individuals with occult nodal disease who might benefit from regional lymphadenectomy and adjuvant therapy.[7,8,9,10]

  The International Multicenter Selective Lymphadenectomy Trial (MSLT-1 [JWCI-MORD-MSLT-1193]) included 1,269 patients with intermediate-thickness (defined as 1.2 mm-3.5 mm in this study) primary melanomas.[11] There was no melanoma-specific survival advantage (the primary endpoint) for those patients randomly assigned to wide excision plus SLN biopsy followed by immediate complete lymphadenectomy for node positivity versus patients randomly assigned to nodal observation and delayed lymphadenectomy for subsequent nodal recurrence at a median of 59.8 months.[11][Level of evidence: 1iiB]

  This trial was not designed to detect a difference in the impact of lymphadenectomy in patients with microscopic lymph node involvement.[11]