Optimal excision margins for primary cutaneous melanoma: a systematic review and meta-analysis.

OBJECTIVE To determine in patients with localized primary melanoma of the trunk or extremities the optimal excision margin that achieves the highest disease-free survival and overall survival and the lowest local recurrence rate. DATA SOURCES Trials comparing 2 different excision margins were identified by searching MEDLINE from 1966 to May 2002 using the term "melanoma," subheading "surgery," and limiting the search to human studies and randomized controlled trials (RCTs). Additional studies were found using the MeSH term "surgical procedures, operative," combining with "melanoma," and limiting to human studies. We searched EMBASE and the Cochrane Library in May 2002 using similar terminology. No language restriction was applied. STUDY SELECTION We selected studies for the overview using the following inclusion criteria: design--an RCT with wide excision versus narrower excision (margin width was not specified a priori); population--adult patients (> 18 yr) with cutaneous melanoma of the trunk or extremities without evidence of metastasis; intervention--surgical excision of the primary melanoma; and outcomes--at least 1 of overall survival, disease-free survival, local recurrence, wound complications and necessity for skin grafting. DATA EXTRACTION Information was abstracted for each outcome reported in the studies, and results were pooled by consensus. Statistical analysis was performed using RevMan 4.1 (The Cochrane Collaboration) software program. Relative risk and risk difference were reported with 95% confidence intervals. The number needed to harm was calculated for the need for skin grafting by taking the inverse of the risk difference. DATA SYNTHESIS Three trials and their follow-up studies met the inclusion criteria and included 2087 adults with localized cutaneous melanoma of the trunk or extremities. No statistically significant differences were found between wide surgical excision (margins ranging from 3-5 cm) and narrower surgical excision (margins ranging from 1-2 cm) with respect to mortality, disease-free survival or local recurrence rate. CONCLUSIONS Surgical excision margins no more than 2 cm around a melanoma of the trunk or extremities are adequate; overall survival, disease-free survival and recurrence rate are not adversely affected compared with a wider excision. There is more data to support a 2-cm margin than a 1-cm margin as the minimum margin of excision. Surgical margins should be no less than 1 cm around the primary melanoma.