PS100 measurement and Tc99m-sestamibi scintigraphy for the diagnosis of lymph node metastasis in malignant melanoma and detection of their possible chemo-resistance

Interest of association of serum S-100 β level and 99m Tc-sestamibi scintigraphy for the detection of lymph node malignant melanoma metastasis and multidrug resistance phenomenon. The aim of our study was to evaluate the interest of S100 βserum level during the followup of patients with previously resected malignant melanoma in addition with 99m Tc-MIBI scintigraphy and the detection of MDRl gene by RT-PCR. 37 patients with a clinically questionable lymph node were enrolled in the study. Sensitivity and specificity were respectively 95.5% and 86.5% for S100 β serum level, 95% and 85% for MIBI scintigraphy. An overexpression of MDRI gene was observed in 6 patients. When no MIBI uptake was seen, the confrontation with the S100 βserum level isolated the patients with lymph node metastasis and overexpression of MDRI gene. Thus S100 βserum level could improve the follow-up of malignant melanoma. (authors)