METHODS: Patients treated at four tertiary centres were included. Cumulative incidence curves were calculated for recurrences.
RESULTS: A total of 100 patients (57 males, 57%) were included with 103 SCs. The median age was 72 (range, 15-95) years with a median follow-up of 52 (interquartile range [IQR], 24-93) months. Most SCs were located (peri)ocular (49.5%). Of all SCs, 17 locally recurred (16.5%) with a median time to recurrence of 19 (IQR, 8-29) months. The cumulative incidence probability for recurrence was statistically higher for (peri)ocular tumours (p = 0.005), and for positive resection margins (p = 0.001). Two patients presented with lymph node metastases and additional seven patients (8.7%) developed lymph node metastases during follow-up with a median time to metastases of 8 (IQR, 0.5-28) months. Three patients had concurrent in-transit metastases and one patient also developed liver and bone metastases during follow-up.
CONCLUSIONS: SC is a rare, yet locally aggressive tumour. Positive resection margins and (peri)ocular SCs are more frequently associated with local recurrence. SC infrequently presents with locoregional or distant metastases.