Sentinel lymph node biopsy for high-risk cutaneous squamous cell carcinoma: clinical experience and review of literature

Abstract

High-risk cutaneous squamous cell carcinoma (SCC) is associated with an increased risk of metastases. The role of sentinel lymph node (SLN) biopsy in these patients remains unclear. To address this uncertainty, we collected clinical data on six patients with clinical N0 high-risk SCC that underwent SLN biopsy between 1999 and 2006 and performed a literature review of SLN procedures for SCC to study the utility of SLN biopsy. There were no positive SLN identified among six cases and there was one local and one distant recurrence on follow-up. Literature review identified 130 reported cases of SLN biopsy for SCC. The SLN positivity rate was 14.1%, 10.1%, and 18.6%; false negative rate was 15.4%, 0%, and 22.2%; and the negative predictive value was 97.8%, 100%, and 95.2% for all sites, head/neck, and truncal/extremity sites, respectively. SLN biopsy remains an investigational staging tool in clinically node-negative high-risk SCC patients. The higher false negative rate and lower negative predictive value among SCC of the trunk/extremity compared to SCC of the head/neck sites suggests a more cautious approach when treating patients with the former. Given the paucity of long-term follow up, an emphasis is placed upon the need for close surveillance regardless of SLN status.

Sentinel node biopsy for high-risk cutaneous squamous cell carcinoma

“…22,23 Our study found 6 of 26 cases (23.1%) to be SN-metastasis positive, which is within the range of past reports. No instances of regional lymph node metastasis occurred in the cases deemed SNmetastasis negative during the observational period in our study.…”

Utility of sentinel node biopsy in patients with high-risk cutaneous squamous cell carcinoma

“…Several authors have examined the utility of SLNB as a method for staging patients with non-melanoma skin cancer who are at high risk for metastasis. 1,2,6 These studies suggested that it might be useful in patients with high-risk cutaneous squamous cell carcinoma. Cherpalis et al suggest that patients with lymph node metastasis may be cured by lymph node dissection and radiotherapy and SLNB would therefore be an important staging tool and in planning the right treatment for patients with high-risk cSCC.…”

“…Risk factors for metastasis include tumor size, localization, Clark level IV and above, poorly differentiated histological subtype, immunosuppression, and perineural invasion. 2 Patients with lymph node metastasis have a 5-year survival ranging from 26 to 34% 1 The utility of sentinel lymph node biopsy (SLNB) in staging of melanoma is well established as an independent prognostic factor for survival and has proved to prolong the disease-free survival. 3e5 It has yet not shown to improve the overall survival but SLNB is still widely accepted as a minimally invasive procedure with high accuracy for detection of nodal metastases and as a diagnostic tool.…”

“…The prognosis is generally favorable with an overall metastatic rate of 5% and the disease is generally curable with surgical therapy. 1 However, a small subset of cutaneous squamous cell carcinoma is characterized by aggressive behavior, increased risk of metastasis and lower survival. Risk factors for metastasis include tumor size, localization, Clark level IV and above, poorly differentiated histological subtype, immunosuppression, and perineural invasion.…”

Non-melanoma Skin Cancer in Canada Chapter 5: Management of Squamous Cell Carcinoma

“…Sentinel lymph node biopsy-a minimally invasive technique for identifying occult nodal metastases-is used commonly in breast cancer and cutaneous melanoma, but the value of this method in high-risk SCC is not well established. 6,13,32,33 …”