Hypothesis: to address if diagnosis of obstructive sleep apnea before or during the extending check-up is a risk factor toward metastasis for melanoma stage ≥ tIIaN0M0 Study design: Adult patients with a Breslow's Thickness ≥ 1mm coming to the surgery consultation will have a nocturnal oximetry for screening of obstructive sleep apnea. Patients having an abnormal nocturnal oximetry will be explored by polysomnography in order to detect sleep apnea syndrome. Patients with sleep apnea will be treated.