Introduction: In melanoma, lymph node status constitutes the most important prognostic factor among patients with locoregional disease. It has been postulated that elderly patients present less metastatic involvement in sentinel lymph node (SLN). Our objective was to analyse the results and evolution of patients ≥ 70 years-old with cutaneous melanoma in whom sentinel lymph node biopsy (SLNB) was carried out.

Methods: Retrospective analysis of 194 patients with primary CM who had a SLNB between 2005 and 2020 was included. Demographic and tumour data, SLN status, recurrence rate, morbidity and evolution were evaluated. Patients were divided into two groups according to age: Group 1 (<70 years old) and Group 2 (≥70 years old).

Results: One hundred and fifty patients were included in Group 1 and 44 patients in Group 2. Median Breslow thickness was 1.7 mm in Group 1 and of 2 mm in Group 2 (p = 0.015).Forty-seven patients had positive SLNB; 38 (25%) belonged to Group 1 and 9 (20.5%) to Group 2 (p = 0.55). Recurrence was found in 34 patients: 25 belonging to Group 1 and 9 corresponding to Group 2 (p = 0.65). Morbidity was of 4% in Group 1 and 9% in Group 2 (p = 0.23). With an average follow-up of 30.6 months, 5-year overall survival was of 87% in Group 1 and of 63% in Group 2 (p = 0.04).

Conclusion: Advanced age was not associated with differences regarding positivity of SLN and recurrence but difference in overall survival was observed. According to our results and the low morbidity rate, we consider SLNB should not be omitted in such age group, since it improves staging and gives the possibility to evaluate adjuvant treatment.