Narrow Excision Margins for Diverse Histological Subtypes of Cutaneous Melanoma in Children and Adults: A Systematic...

Wide local excision (WLE) is a standard component of cutaneous melanoma management, although prospective evidence supporting current margin recommendations remains limited. Surgical margins have progressively decreased. However, six randomized clinical trials comparing wider (3-5 cm) vs. narrower (1-2 cm) margins did not demonstrate significant reductions in local recurrence (LR) or survival benefits. Furthermore, wider margins are associated with increased morbidity and healthcare costs.

We systematically reviewed relevant published studies up to and including December 2025 to compare LR and survival outcomes between standard WLE and no or narrow-margin excisions. The analysis included adult and pediatric cases of superficial spreading, nodular, acral, and desmoplastic cutaneous melanoma; lentigo maligna was excluded.

No prospective studies were found comparing WLE to the omission of WLE for cutaneous melanoma. Two retrospective studies reported no significant differences in LR or overall survival (OS) in patients who did not undergo WLE (n = 453). Regarding lateral margins, 30 retrospective studies were identified. Collectively, these studies suggest that narrower margins than those currently recommended are not associated with worse LR, disease-free survival, or OS for melanoma in situ and pT1-pT3 tumors (Breslow index ≤ 4 mm). However, findings for pT4 melanomas (Breslow index > 4 mm) remain inconsistent. Analysis of deep margins (n = 5 retrospective studies) largely supported more superficial excision strategies than current guidelines. Regarding acral melanoma, seven retrospective studies were located, all of which reported that narrower and shallower margins-including the preservation of plantar fat-did not adversely affect LR or survival. Conversely, in cases of desmoplastic melanoma, two retrospective studies were found with conflicting results regarding LR. In the pediatric population, evidence remains scarce; two retrospective studies evaluating narrow excision margins revealed no adverse impact on OS.

Current evidence suggests that narrower lateral margins and shallower deep excision strategies could be oncologically safe. However, the absence of an observed association with higher rates of LR or worse survival outcome should not be interpreted as proof of non-inferiority to standard WLE, given the predominance of observational data, heterogeneity across studies, and limited statistical power in smaller cohorts. High-quality prospective randomized trials are required. Ongoing randomized trials (MelMART-II, WoW, and ICEMAN) will play a key role in refining future surgical margin recommendations.