Sentinel Lymph Node Biopsy in High-Risk Cutaneous Squamous Cell Carcinoma: Analysis of a Large Size Retrospective Series

The hidden Australian skin cancer epidemic, high-risk cutaneous squamous cell carcinoma: a narrative review

Deaths from non-melanoma skin cancers (NMSCs) have almost doubled in Australia in recent years. Cutaneous squamous cell carcinoma (cSCC) constitutes approximately 20% of NMSCs, but is responsible for most of the deaths. Most skin cancers are easy to diagnose and treat and therefore cSCC are often trivialised; however, there is a high-risk subgroup of cSCC (HRcSCC) that is associated with a high risk of metastasis and death. The definition of early HRcSCC and our ability to identify them is evolving. Many significant prognostic factors have been identified, but a universally accepted prognostic index does not exist. Guidelines for workup, treatment, and follow-up leave many important decisions open to broad interpretation by the treating physician or multidisciplinary team. Some of the treatments used for metastatic cSCC are not supported by robust evidence and the prognosis of metastatic cSCC is guarded. In this review, we highlight the rapid rise in NMSC deaths and discuss some of the deficiencies in our knowledge of how to define, diagnose, stage, and manage HRcSCC.

Sentinel lymph node biopsy versus observation in high-risk cutaneous squamous cell carcinoma in immunosuppressed and immunocompetent patients: An inverse probability of treatment weighting study

BACKGROUND

The survival benefit of sentinel lymph node biopsy (SLNB) in immunocompetent and immunosuppressed patients with high-risk cutaneous squamous cell carcinoma (cSCC) has not been established.

OBJECTIVE

To determine whether SLNB improves disease-specific survival (DSS) in high-risk cSCC. Secondary objectives were to analyse disease-free survival, nodal recurrence-free survival and overall survival (OS).

METHODS

Multicentre, retrospective, observational cohort study comparing survival outcomes in immunosuppressed and immunocompetent patients treated with SLNB or watchful waiting. Inverse probability of treatment weighting was used to adjust for possible confounding effects.

RESULTS

We studied 638 tumours in immunocompetent patients (SLNB n = 42, observation n = 596) and 173 tumours in immunosuppressed patients (SLNB n = 28, observation n = 145). Overall, SLNB was positive in 15.7% of tumours. SLNB was associated with a reduced risk of nodal recurrence (NR) (hazard ratio [HR], 0.05 [95% CI, 0.01-0.43]; p = 0.006), disease specific mortality (HR, 0.17 [95% CI, 0.04-0.72]; p = 0.016) and all-cause mortality (HR, 0.33 [95% CI, 0.15-0.71]; p = 0.004) only in immunocompetent patients.

CONCLUSIONS

SLNB was associated with improvements in NR, DSS and OS in immunocompetent but not in immunosuppressed patients with high-risk cSCC.

Sentinel lymph node biopsy versus observation in high risk cutaneous squamous cell carcinoma of head and neck: a propensity score matching analysis

Sentinel lymph node biopsy (SLNB) has gained considerable attention in the management of head and neck cutaneous squamous cell carcinoma (HNcSCC). The aim of this study was to compare the oncologic outcomes between observation and SLNB in cN0 high-risk HNcSCC patients. We retrospectively enrolled patients from the SEER database and evaluated the impact of observation versus SLNB on disease-specific survival (DSS) and overall survival (OS) using a Propensity Score Matching (PSM) analysis. A total of 9804 patients were included, with 1169 cases treated by SLNB. Successful retrieval of the sentinel lymph node was achieved in 1130 procedures. After PSM and subsequent multivariate analysis, SLNB was found to be an independent predictor for improved DSS, with a hazard ratio of 0.70 (95% confidence interval: 0.56-0.86). In patients presenting with two or three high-risk factors, SLNB was associated with better DSS (p = 0.021 and p = 0.044), but similar OS (p = 0.506 and p = 0.801) when compared to observation. However, in patients exhibiting four high-risk factors, SLNB demonstrated significantly improved DSS (p = 0.040) and OS (p = 0.028) compared to observation. Our findings suggest that SLNB is a highly feasible technique in HNcSCC and provides significant survival benefits. It is strongly recommended in patients with two or more high-risk factors, as it can help guide treatment decisions and improve patient outcomes.

European consensus-based interdisciplinary guideline for invasive cutaneous squamous cell carcinoma: Part 2. Treatment-Update 2023

In order to update recommendations on treatment, supportive care, education, and follow-up of patients with invasive cutaneous squamous cell carcinoma (cSCC), a multidisciplinary panel of experts from the European Association of Dermato-Oncology (EADO), the European Dermatology Forum (EDF), the European Society for Radiotherapy and Oncology (ESTRO), the European Union of Medical Specialists (UEMS), the European Academy of Dermatology and Venereology (EADV), and the European Organisation of Research and Treatment of Cancer (EORTC) was formed. Recommendations were based on an evidence-based literature review, guidelines, and expert consensus. Treatment recommendations are presented for common primary cSCC (low risk, high risk), locally advanced cSCC, regional metastatic cSCC (operable or inoperable), and distant metastatic cSCC. For common primary cSCC, the first-line treatment is surgical excision with postoperative margin assessment or micrographically controlled surgery. Achieving clear surgical margins is the most important treatment consideration for patients with cSCCs amenable to surgery. Regarding adjuvant radiotherapy for patients with high-risk localised cSCC with clear surgical margins, current evidence has not shown significant benefit for those with at least one high-risk factor. Radiotherapy should be considered as the primary treatment for non-surgical candidates/tumours. For cSCC with cytologically or histologically confirmed regional nodal metastasis, lymph node dissection is recommended. For patients with metastatic or locally advanced cSCC who are not candidates for curative surgery or radiotherapy, anti-PD-1 agents are the first-line systemic treatment, with cemiplimab being the first approved systemic agent for advanced cSCC by the Food and Drugs Administration/European Medicines Agency. Second-line systemic treatments for advanced cSCC, include epidermal growth factor receptor inhibitors (cetuximab) combined with chemotherapy or radiotherapy. Multidisciplinary board decisions are mandatory for all patients with advanced cSCC, considering the risks of toxicity, the age and frailty of patients, and co-morbidities, including immunosuppression. Patients should be engaged in informed, shared decision-making on management and be provided with the best supportive care to improve symptom management and quality of life. The frequency of follow-up visits and investigations for subsequent new cSCC depends on underlying risk characteristics.

Sentinel lymph node biopsy in high-risk cutaneous squamous cell carcinoma of the head and neck: Systematic review and meta-analysis

The aim of our study was to better define the role of sentinel lymph node biopsy (SLNB) in high-risk cutaneous squamous cell carcinoma of the head and neck (cSCCHN). A systematic review and meta-analysis was performed according to the PRISMA statement. Seven-hundred and five patients were included from 20 studies. The pooled SLN identification rate was 98.8% (95%CI: 97.0-99.8). The median number of SLN excised was 3.6 (n = 371, 95%CI: 2.0-4.4). The pooled SLNB positive rate and cumulative regional recurrence rate (RRR) in negative SLNB were 5.6% (95%CI: 2.6-9.6) and 2.9% (95%CI: 0.5-7.2), respectively. The high SLN identification rate demonstrates SLNB feasibility in cSCCHN. The low SLNB positive rate and the relatively high RRR raise some doubts concerning its clinical utility. Further studies are mandatory to define predictors of lymph node metastases able to better select patients that may benefit from a SLNB.