Sentinel lymph node (SLN) biopsy is currently a valuable and reliable diagnostic procedure for precise staging of malignant melanoma (MM) patients. We assessed whether the genetic testing in SLNs from MM patients can be an independent prognostic factor. A retrospective study analysis was conducted for 35 patients (ratio of men to women, 17:18) who underwent SLN biopsy and primary cutaneous melanoma excision in our institution from January 2013 to June 2018. The median patient age was 71 years (range, 13-83 years). The number of patients classified by clinical subtype were 7 chronic sun-induced damage (CSD), 23 non-CSD and 5 acral. According to the 8th AJCC staging classification, 11 patients (31%) had stage I, 9 patients (26%) had stage II, 1 patient (3%) had stage IIIA, 2 patients (6%) had stage IIIB, and 9 patients (26%) had stage IIIC. Fifteen patients (43%) were histopathological positive in the SLNs. Twelve patients (34%) underwent following extensive lymph nodes dissection. Eleven patients (31%) had tumor thickness more than 4.0mm.               
Median follow-up time was 36 months (range, 1-74 months). We analyzed mRNA gene expression in the SLNs using quantitative real-time PCR (qRT-PCR). The gp100, MART1, and tyrosinase mRNA gene expression level of ddCt measurement value showed correlation with unfavorable prognosis in OS rate.

The prognosis prediction of cutaneous melanoma patients using quantitative real-time PCR from sentinel lymph node.