DS16 Clinicopathological features of metastatic squamous cell carcinoma treated with Mohs micrographic surgery: a case series

Abstract

Cutaneous squamous cell carcinoma (cSCC) is a keratinocyte tumour with inherent metastatic potential. Approximately 4% of cSCCs metastasize locoregionally and/or distally. Mohs micrographic surgery (MMS) is efficacious, with cure rates in selected cases of 95–99%. Diagnoses of cSCC treated at St James’s Hospital between the years 2010 and 2019 were identified via histopathology reports. Clinicopathological and treatment data in cases with metastatic disease were collected. Nodal metastasis was defined as biopsy-confirmed cSCC in locoregional lymph nodes and/or supporting radiological evidence. During the timeframe, 3455 cSCCs occurred in 2522 patients. Metastatic disease was identified in 116 patients, with complete data available in 105 cases. Six patients had undergone MMS to the primary tumour. Mean age at time of surgery was 75.6 years (range 65–85); five patients were male. Tumours were located on the cheek (n = 2), ear (n = 2), lower eyelid and nasal tip. Mean time to first metastasis was 6.67 months (range 2–16). Two patients were immunosuppressed at time of metastasis. All patients demonstrated high-risk cSCC features, with four patients demonstrating very-high-risk features as defined by the British Association of Dermatologists. One patient received adjuvant radiotherapy prior to detectable metastasis. All patients were discussed at either skin or head and neck multidisciplinary team (MDT) meetings. No patient received preoperative imaging. This series highlights the importance of risk stratification in cSCC management, irrespective of treatment modality. Consideration should be given to patient age and relative immune status, with dedicated locoregional imaging being guided by MDT discussion.