Value of frozen-section analysis of sentinel lymph nodes for primary cutaneous malignant melanoma.

Abstract

To analyze a large, single-institution experience with routine frozen section (FS) of the sentinel lymph node (SLN) in patients with primary cutaneous melanoma. Controversy exists over the utility of intraoperative FS analysis of the SLN in patients with primary cutaneous melanoma. All patients with clinically node-negative cutaneous melanoma undergoing SLN biopsy from 1991 to 1999 were identified from a prospective database. All SLNs were examined by FS. Step-sectioning and immunohistochemistry of permanent section were performed for SLNs negative by FS. At least one SLN was identified in 98% (360/368) of patients. There were 74 (20%) SLNs positive on permanent section; FS was positive in 59% of these. The accuracy, sensitivity, and specificity of FS were 92%, 59%, and 100%. Because isolated recurrence developed in six patients in the nodal basin in which the SLN was negative, the failure rate was 1.7%. The false-negative rate for SLN biopsy was 7.5%. Because the prevalence of metastases within the SLN and sensitivity of FS analysis are low, routine use of FS for all patients undergoing SLN biopsy is not recommended.