Another pitfall of sentinel lymph node biopsy: scar after lymph node biopsy 30 years ago revealed a sentinel lymph node.

In recent years, sentinel lymph node (SLN) biopsy has been used as a diagnostic and prognostic indicator for a number of tumors, including malignant melanoma. Sentinel lymph node biopsy using combined dye-radiotracer technique improved the detection rate and made the method easier. However, many pitfalls on the SLN procedure have been reported. Herein, we present a new pitfall. A formation of scar and lymph node tissue was detected as a SLN 30 years after lymph node biopsy.