Abstract
One step melanoma surgery (OSMS) is applicable to all patients with clear clinical and dermatoscopic criteria for thin cutaneous melanomas or melanoma in situ lesions, even without the need for preoperative tumour thickness measurement. Amelanotic melanomas and melanomas with clinical and dermatoscopical features for regression zones could be problematic when applying the OSMS. The methodology could be also applicable to all groups of patients where the tumour thickness could be measured preoperatively/by ultrasound (while in parallel also determining the status of the locoregional lymph nodes). For tumours with a tumour thickness between 2 and 4 mm, but also over 4mm the OSMS seems to be the correct choice.