9. Management of Widely Metastatic and Unresectable Cutaneous Squamous Cell Carcinoma

Metastatic cSCC most frequently originates from the head and neck with metastases located in regional lymph nodes or the parotid gland. However, axillary and groin nodal metastases, and lung metastases can also occur. Half of all metastatic cases will develop local recurrence first. Thus, patients who develop locally recurrent cSCC after clear-margin excision (Mohs or non-Mohs) should be considered at risk for metastasis. Current staging of lymph node metastases for cSCC is based on the diameter, number, and laterality of lymph nodes involved. Treatment of nodal metastatic disease primarily consists of surgery and radiation. Chemotherapy and epidermal growth factor receptor (EGFR) antagonist therapies are generally reserved for locoregional disease that has not been controlled with surgery and/or radiation, and for distant metastases. However, early adjuvant therapy shows promise and requires further study to define appropriate patient populations. Future treatment models based on targeted therapies require a greater understanding of the genetic profile of cSCCs.