Head and neck cutaneous melanoma: an influence of surgical resection margin on long-term results

Introduction. Despite of recent breakthrough in the drug therapy of metastatic melanoma surgical treatment remains the key method of treatment of primary cutaneous melanoma. Resection margin of ≥3 centimeters has been considered as radical for decades. Hence, 3 decades ago the main challenge of surgical treatment of primary cutaneous melanoma was the aspect of optimal resection margin. Recent studies contest the belief about the necessity of wide resection. The aim: our study was conducted to evaluate an influence of resection margin volume on long-term results of treatment of head and neck primary cutaneous melanoma. Materials and methods. 174 patients with head and neck cutaneous melanoma were included in the study (inclusion interval: 1995-2014). In order to establish real resection boundaries we used the predefined index of cutaneous flap contraction (median: 30%). Therefore, for subsequent statistical analysis patients were defined into 3 subgroups: 1) resection margin <0.5 cm; 2) resection margin from 0.6 cm till 1 cm and 3) resection margin >1.0 cm. Results. Disease free survival did not correlate with resection margin. It was better (77,3%) with minimal resection margin and the worst with maximal resection margin (38,7%). In other words an increase in resection margin has no influence on long-term results. Conclusions. According to international clinical guidelines resection margin ≥1 сm is considered sufficient for T1-2 and 2 cm - for T3-4 cutaneous melanoma of all localizations. Our retrospective study with regard to the predefined index of cutaneous flap contraction was characterized by resection margin <1.0 cm for all stages of melanoma (T1-4) in most cases. We used ROC-curves to evaluate optimal resection margins in relation to the melanoma thickness. Optimal resection margin for tumor <2 mm was defined as 0.46 mm (p=0.13); 2.01-4.0 mm - 0.58 mm (p=0.002); >4 mm - 0.72 mm (p=0.016). Resection margin of 1.0 cm is adequate for all stages of head and neck cutaneous melanoma, even when the tumor thickness exceeds 4 mm. Five-year disease-free survival in the subgroup of resection margin <1.0 cm was 2-fold higher than in subgroup of resection margin >1 cm (59.4% vs 27.3%); p=0.00003; significant difference.

cutaneous melanoma, head and neck, resection margin, index of cutaneous flap contraction, disease-free survival