S100-EPISPOT: A New Tool to Detect Viable Circulating Melanoma Cells.

Metastatic melanoma is one of the most aggressive and drug-resistant cancers with very poor overall survival. Circulating melanoma cells (CMCs) were first described in 1991. However, there is no general consensus on the clinical utility of CMC detection, largely due to conflicting results linked to the use of heterogeneous patient populations and different detection methods. Here, we developed a new EPithelial ImmunoSPOT (EPISPOT) assay to detect viable CMCs based on their secretion of the S100 protein (S100-EPISPOT). Then, we compared the results obtained with the S100-EPISPOT assay and the CellSearch® CMC kit using blood samples from a homogeneous population of patients with metastatic melanoma. We found that S100-EPISPOT sensitivity was significantly higher than that of CellSearch®. Specifically, the percentage of patients with ≥2 CMCs was significantly higher using S100-EPISPOT than CellSearch® (48% and 21%, respectively; p = 0.0114). Concerning CMC prognostic value, only the CellSearch® results showed a significant association with overall survival (p = 0.006). However, due to the higher sensitivity of the new S100-EPISPOT assay, it would be interesting to determine whether this functional test could be used in patients with non-metastatic melanoma for the early detection of tumor relapse and for monitoring the treatment response.

Florid pseudoepitheliomatous hyperplasia related to tattoo: a case report.

Pseudoepitheliomatous hyperplasia is a benign condition defined by an exuberant proliferation of the epithelium with downward progression into the dermis. It may occur in reaction to several conditions including chronic cutaneous wound. We describe an unusual case of a florid pseudoepitheliomatous hyperplasia mimicking a well-differentiated squamous cell carcinoma, restricted to the red part of a rose tattoo.