Delayed regional metastasis from small face/scalp cutaneous squamous carcinoma: outcomes and predictors

CSCC (cutaneous squamous cell carcinoma) of the face/scalp generally has a favorable outcome. However, patients with delayed regional metastasis from scalp/facial CSCC do very poorly. Historically, prophylactic treatment of the N0 neck for the T1-T2 (as staged in the AJCC 7th edition) face/scalp cancers has not been recommended. This study aims to determine predictors of delayed regional metastases in < 4 cm CSCC of the face and scalp.

We retrospectively analyzed medical records of patients diagnosed regional metastasis of CSCC of the scalp/face at least 6 months after the diagnosis of the primary CSCC at a tertiary academic head and neck clinic during a period between 2012 and 2018.

A total of 50 patients with CSCC of the face/scalp were diagnosed and treated for delayed cervical lymph node metastasis during a 6-year period. All patients were male. Areas affected were the scalp, cheeks, and forehead. No patient had neck lymph node metastases at initial presentation for their scalp/face cancer. The presence of perineural invasion in the primary tumor was the only observed predictor of delayed neck lymph node recurrence. We did not observe an association between diameter/depth of the primary skin tumor or lymphovascular invasion and the presence of regional lymph node recurrence.

In our review, perineural invasion (PNI) was the one factor predictive of delayed regional lymph node metastasis. This observation confirms the use of PNI to upstage even small CSCC to T3. Prophylactic treatment of the neck in patients with small scalp/face cancers with PNI should be strongly considered, especially in the age of immunotherapy.