Worse outcome for patients with recurrent melanoma after negative sentinel lymph biopsy as compared to sentinel-positive patients

BackgroundThe long-term outcome of patients with melanoma who had recurrence after negative sentinel lymph node (SLN) biopsy has rarely been evaluated systematically.MethodsWe searched our databases for melanoma patients with SLN biopsy from the end of 1999 and the beginning of 2011. Data was analyzed using uni- and multivariate statistics as well as Kaplan–Meier curves.ResultsData of 651 patients with melanoma was available for statistics. We observed 451 (69.3%) patients with negative SLN who had no evidence of disease recurrence during follow-up. Recurrence in SLN negative patients was found in 50 (7.7%) cases. Tumor subtypes such as invasive lentigo maligna melanoma and acral melanoma (odds ratio 15.2, P = 0.015) and tumor thickness > 2 mm (odds ratio 3.1, P = 0.0017) were independent predictors for recurrence in patients with negative SLN. Patients with negative SLN and subsequent recurrence had a significantly (P = 0.036) reduced 5-year melanoma-specific survival (MSS) when compared with positive SLN patients. Recurrence of disease in positive SLN patients was observed after a median of 39 months when compared to patients with negative SLN and recurrence (28 months, P = 0.0079). Negative SLN with recurrence was an independent predictor for worse recurrence free and melanoma-related survival.ConclusionsPatients with negative SLN and recurrence experience earlier disease relapses and poorer MSS when compared to patients with positive SLN status implicating that more stringent follow-up procedures are warranted in patients with higher tumor thickness and invasive lentigo maligna and acral melanoma, despite a negative SLN.