Clinical risk factors and prognostic significance of local recurrence in cutaneous melanoma.

Background: True local recurrence (LR) means clinically detectable regrowth of parts of the tumour which were not completely excised. In the literature the term 'LR' has been used in a vague and inconsistent manner that may include satellite and in-transit metastasis.

Objective: The aim of this study was to establish clinical, histological and surgical risk factors for the manifestation of LR and to evaluate the prognostic significance of LR.

Study Design: Data from 3960 Stage I and II melanoma patients who visited the melanoma clinic of the Department of Dermatology at the University of Tuebingen from 1980 to 1999 were documented in a prospective manner. A retrospective comparative analysis of patients with and without LR was performed.

Results: Of all patients 1.4% had a LR as a first recurrence and 1.7% had a LR in the course of the follow-up period. LR were most frequent after previous clinical or histological misdiagnosis and inadequate therapy. In the univariate analysis significant risk factors for LR-free survival were age, tumour surface area, locality, tumour thickness, level of invasion, histological type, associated naevus, surgery (one step vs. multiple steps) and compliance with recommended excision margins. In the multivarate analysis the factors locality (P < 0.0001), tumour thickness (P = 0.0086) and compliance with recommendations on excision margins (P = 0.014) were significant independent risk factors for the manifestation of LR. The overall survival of patients with LR as first progression did not significantly differ from the overall survival of the other patients with melanoma (P = 0.60).

Conclusion: True LR is a rare event for which tumour locality, tumour thickness and surgery are independent risk factors. The occurrence of LR might not impair the prognosis of melanoma patients. However, in the published literature numerous definitions of 'LR', including lymphogenic metastasis, complicate comparison.