V63: Oncological Outcome After Lymph Node Dissection for Cutaneous Squamous Cell Carcinoma

Although cutaneous squamous cell carcinoma (cSCC) is common, little is known about clinical outcome in case of (recurrent) advanced disease. The aim of this study was to describe the clinical course, treatment and prognosis after lymph node dissection (LND) for cSCC at all primary locations.


Methods:

A retrospective search at three tertiary referral centres was performed to identify patients with lymph node metastases from cSCC between 1995 and 2018. Prognostic factors were identified by uni- and multivariable Cox regression analysis.


Results:

A total of 268 patients were identified with a median age of 74 (Interquartile range (IQ) 65-82).  80% of the tumors were located in the head and neck region. The median time to lymph node metastases was 10 months (IQ 5-19) after surgery for the primary. All lymph node metastases were treated with LND. 65% subsequently underwent adjuvant radiotherapy (n=165). The median follow-up after LND was 18 months (IQ, 10-38). After LND, 94 (35%) patients developed recurrent disease. Patients with more than one positive lymph node had an increased risk for recurrent disease in multivariable analysis (HR, 2.15; 95%CI 1.17-3.94). Of all patients, 165 (62%) died during follow-up of whom 77 (47%) due to cSCC. Of the 94 patients who developed  recurrent disease, 82 (87%) died during follow-up, of whom 63 (67%) due to disease. Median overall survival (OS) and disease-specific survival (DSS) for all patients were 27  (IQ, 11-99) and 172 months (IQ, 14 –NR). The 5-year OS- and DSS rate were 36% and 52%, respectively. In multivariable analysis, disease-specific death was significantly higher in immunosuppressed patients (HR, 3.26; 95%CI 1.57-6.78), primary tumors larger than 2 cm (HR, 2.59; 95%CI 1.04-6.48), and patients with more than one positive lymph node (HR, 2.14; 95%CI 1.14-4.01).


Conclusions:

This study shows that LND for patients with lymphatic metastasized cSCC  leads to a 5-year DSS of 52%. After LND approximately one-third of the patients develop recurrent disease both loco regionally and  distantly, which underscores the need for better treatment options for loco regionally advanced cSCC. The size of the primary tumor, number of positive lymph nodes, and immunosuppression are independent predictors for recurrence and/or disease-specific death after LND for cSCC.