Inclusion Criteria:

• Patients with malignant melanoma in AJCC stages Ib / II
• Tumor depth of ≥1.0 mm
• Age ≥18 years to ≤75 years
• Have a primary melanoma that is cutaneous (including head, neck, trunk, extremity, scalp, palm, sole, subungual skin tissues
• Eastern Cooperative Oncology Group (ECOG) performance status 0-1
• Life expectancy of at least 5 years from the time of diagnosis, not considering the melanoma in question, as determined by the principal investigator (PI)
• Willing to return to the trial center for follow-up examinations and procedures as outlined in the protocol
• Randomization must be completed no more than 120 days following the diagnostic biopsy of the primary melanoma
• Negative pregnancy test for female and effective contraception for both male and female subjects if the risk of conception exists
• Signed written informed consent prior to the performance of any trial specific procedure

Exclusion Criteria:

• History of previous or concurrent (i.e., second primary) invasive melanoma
• Primary melanoma of the eye, mucous membranes or internal viscera
• Any additional solid tumor or hematologic malignancy during the past 5 years except skin lesions of squamous cell carcinoma, basal cell carcinoma, or uterine cervical cancer
• Skin grafts, tissue transfers or flaps that have the potential to alter the lymphatic drainage pattern from the primary melanoma to a lymph node basin
• Hypersensitivity to the active substance(s), to any of the excipients or to any of the components of the labelled radiopharmaceutical
• Extensive previous surgery in the region of the primary tumor site or complete lymph node dissection (CLNDs) or sentinel lymphadenectomy (SLs) (before evaluation of the current melanoma) that may have altered the lymphatic drainage pattern from the primary cutaneous melanoma to a potential lymph node basin
• Organic brain syndrome or significant impairment of basal cognitive function or any psychiatric disorder that might preclude participation in the full protocol, or be exacerbated by therapy (e.g., severe depression)
• Pregnancy (absence to be confirmed by ß-human chorionic gonadotropin test) or lactation period
• Medical or psychological conditions that would not permit the subject to complete the study or sign informed consent
• Known alcohol or drug abuse
• Participation in another clinical study within the 30 days before registration
• Significant disease which, in the investigator's opinion, would exclude the patient from the study
• Legal incapacity or limited legal capacity