Impact of the time interval between lymph node recurrence and lymphadenectomy on melanoma patient survival

Lymphadenectomy is currently the standard treatment for melanoma patients with palpable lymph node (LN) metastasis. There is no recommendation as to the time when surgery should be performed in France. The aim of this retrospective study was to assess the impact of the time interval preceding lymphadenectomy on patient outcomes. Patients who underwent lymphadenectomy for LN macrometastasis (Stage IIIB/C AJCC) between 2005 and 2012 were included. Both the time interval between the first suspicion of LN recurrence (physical examination and imaging) and lymphadenectomy and the time interval between the multidisciplinary team meeting and lymphadenectomy were recorded. The impact of these time intervals on patient relapse-free survival (RFS) and overall survival (OS) were analysed. The regression optimized (ROP) model was used to identify ghost factors for the Cox model. A total of 154 patients were included. The median time interval between the multidisciplinary team meeting and lymphadenectomy was 22 days (IQR: 6 to 66). The median time interval between the first suspicion of LN recurrence and lymphadenectomy was 59 days (IQR: 15 to 676). Taking into account the effect identified by the regression optimized (ROP) model, these times were associated with an increased risk of recurrence and mortality (p<0.001 and p = 0.01, respectively). Our study demonstrates that increasing the time interval preceding lymphadenectomy significantly reduces patient RFS and OS.