Sentinel lymph node analysis in patients with sweat gland carcinoma.

Overview

BACKGROUND: Sentinel lymph node mapping and biopsy (SLNB) has become a standard staging procedure for patients with cutaneous neoplasms of known metastatic potential. In the current study, the authors explored the use of SLNB in patients with primary sweat gland carcinomas (SGCs). METHODS: Six patients with SGC underwent SLNB. The tumors and lymph nodes were examined using routine hematoxylin and eosin (H&E) stained sections and by immunohistochemistry using antibodies against epithelial membrane antigen and cytokeratins. RESULTS: Metastases were detected in the SLNs of four of the six patients with SGC. One patient with a primary tumor of the neck was found to have bilateral positive SLNs. Tumor deposits were detected by H&E stained sections alone in all but two SLNs, in which the metastatic cells were recognized only with the aid of immunohistochemical stains. Positive non-SLNs were found in two patients after complete regional lymph node dissection was performed. CONCLUSIONS: The high frequency of positive SLNs in this small series suggests that SLNB is a useful staging tool for patients with SGC. As in SLNBs of other tumors, immunohistochemistry appears to facilitate the recognition of small microscopic metastases.