The prognostic significance of histologic regression in cutaneous melanoma

A retrospective evaluation of 201 stage I cutaneous melanomas was performed to investigate the prognostic significance of histological regression (present in 67 cases). Thin melanomas showed regression more frequently than thick lesions (48% less than or equal to 0.75 mm vs 12% greater than 3 mm). The mean disease-free interval was 33.53 months in regressing tumours and 19.9 in non-regressing tumours (p = 0.07): differences between the survival curves were not significant (p = 0.61). Metastases developed in 13 (19.40%) patients with regressing tumours and by 40 (29.85%) patients with non-regressing tumours. Although we observed a higher frequency of regression in thin melanomas we could not demonstrate an influence of regression on disease-free interval and survival.