Clinically misinterpreted melanoma metastases can correctly be diagnosed by ultrasound-guided fine needle aspiration cytology.

Ultrasound-guided fine needle aspiration cytology (US-guided FNAC) of regional nodal basins is increasingly incorporated into the national follow-up schemes of high risk melanoma patients. In this paper we describe an additional added value of US-guided FNAC in the detection and verification of subcutaneous/in-transit metastases. A patient presented with a long lasting, smooth, movable node, close to the scar of the primary melanoma, mimicking a lipoma in every clinical follow-up. Ultrasound at once suspected a metastasis. FNAC was performed within one day of sampling in an outpatient setting, without side effects. A hypothesis of an auto-vaccination in this case could not be proven by examining the T-cell response. Despite the clinically benign aspect of this metastasis, US-guided FNAC can provide diagnosis within 1 day. FNAC is a rapid, cost-effective method, free of complications, of great value in the diagnosis of putative metastases.