[First melanoma metastases after 10 years and more of remission]

36 (3.5%) of 1015 patients who had ten or more years of follow-up after treatment of invasive malignant melanomas (stage I and II, UICC 1978) in Hornheide 1967-1984 developed late metastases. The mean disease-free interval was 12.5 years. These patients were younger (mean age of 45.8 years) compared to the age of all melanoma patients at the time of primary therapy. The rate of late relapses was 2.8% in women (20/705) and 5% in men (16/310). In melanomas located on the trunk or on the legs in male individuals, the relapse was twice as high as in females. The median tumor thickness in patients with late progression was 1.5 mm; in patients without relapse 1.2 mm. The well known association of tumor thickness with the risk of metastases disappeared after a 10 years disease-free interval. The frequency of metastases (3.5%) did not vary in different thickness classes from 0.76 mm to 3 mm or more. Melanomas with a Breslow thickness < 0.75 mm had a risk of only 1.4%. 23 patients (64%) developed distant, only 13 (36%) regional late metastases as first evidence of recurrent disease. The survival of these patients correlated neither to the duration of previous relapse-free follow up, nor to site of the primary lesion nor to sex. It correlated only to the site of metastases: 83% of all patients with distant late metastases had a remaining life time of 14 months or less, but patients with regional metastases survived more than 7 years in 69% of the cases. We have been unable to define risk factors for late metastases.