Abstract
Background and Aims : Sentinel lymph nodes involvement of malignant melanoma has been mainly evaluated by histopathological examination to date. We employed reverse transcriptase-nested polymerase chain reaction (RT-nested PCR) for tyrosinase gene to detect melanoma micrometastases in the sentinel lymph nodes. Patients and Methods : The sentinel lymph nodes from 12 patients with malignant melanoma in clinical stage I, II (classification of the American Joint Committee on Cancer) were examined, introducing histological studies, and tyrosinase RT-nested PCR. Results : Metastatic melanoma cells were identified in 6 of 12 patients by histological studies. Tyrosinase mRNA was detected in 7 of 12 patients by RT-nested PCR. One patient revealed only tyrosinase transcripts. Furthermore, tyrosinase mRNA positive and histologically negative nodes were found out in 3 out of 6 patients whose non-sentinel lymph nodes were evaluated by RT-nested PCR. All of histologically positive nodes were also positive for tyrosinase mRNA by RT-nested PCR. Conclusions : RT-nested PCR for tyrosinase gene is considered as a useful technique to detect micrometastasis in the sentinel lymph nodes.
