Sentinel Lymph Node Biopsy and Staging of Melanoma Using Lymphoscintigraphy and Gamma-probe

Kim, Hong Seok; Song, Ki Hoon; Sim, Seung Joo; Kang, Do Young; Kim, Ki Ho

Abstract

BACKGROUND
In malignant melanoma, the regional nodal status is acknowledged as the most powerful indicator of prognosis. Sentinel lymph node status was formally adopted in 2002 AJCC melanoma staging system. However, there has been no clinical study on sentinel lymph node evaluation, especially using lymphoscintigraphy and gamma probe in melanoma patients in Korea. OBJECTIVE: Our purpose was to assess the usefulness of lymphoscintigraphy and intraoperative gamma probe for the detection of sentinel lymph node in melanoma patients. METHODS: In eight malignant melanoma patients (7 stage I/II, 1 stage III), a lymphoscintigraphy with 99mTc-radiocolloids were injected peritumoral area and the identified first lymph node was considered to be a sentinel node. Once the sentinel lymph node was identified using a hand-held gamma probe for intraoperative mapping, it was excised. And the sentinel node was examined by routine hematoxylin-eosin and immunohistochemical stain (HMB45, S-100). RESULTS: Sentinel nodes were identified in 8 patients all using lymphoscintigraphy and intraoperative gamma probe. Nine sentinel nodes were found in 8 patients, and sentinel lymph node biopsies showed micrometases in 5(55.5%). The location of sentinel nodes was that 3(33.3%) were located in axilla, and 6(66.6%) in groin. The case that had melanoma on back revealed dual lymphatic pathway with 2 sentinel nodes on axilla and inguinal area. CONCLUSIONS: We conclude that preoperative lymphoscintigraphy and intraoperative gamma-probe guided sentinel lymph node biopsy is useful for acute staging and prediction of prognosis for melanoma patients.