Cutaneous squamous cell carcinoma metastatic to parotid - analysis of prognostic factors and treatment outcome

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) comprises 20% of all skin cancer of the head and neck. A minority will metastasize to regional parotid lymph nodes. This study evaluates the St Vincent’s Hospital, Sydney experience between 1996 and 2006. METHODS: A retrospective review was performed of patients who were evaluated in our multidisciplinary head and neck clinic with metastatic cSCC to parotid, and all treatment and pathologic details were reviewed. Statistical analysis, including univariate and multivariate analyses, were performed using Cox proportional hazards regression mode, overall and disease-specific survival were estimated by the Kaplan-Meier method. RESULTS: Sixty-seven patients were identified. Some 90 % were male, and with a mean age of 72.8 years. One died on the first postoperative day. The remaining 66 patients received radiotherapy. For these 66 patients, the two-year and five-year overall survival rate was 0.83 and 0.72, respectively. The two-year and five-year disease-free survival rate was 0.91 and 0.83 respectively. Overall survival was only significantly correlated to the extent of parotidectomy (superficial versus total; P = 0.0256). Margin status was available in 59 patients. The only parameter that significantly correlated with disease-free survival was margin status (close/negative versus positive P = 0.0348). Other parameters of immune suppression, perineural invasion, extra capsular extension, degree of tumour differentiation, number of positive nodes, extent of neck dissection and radiotherapy dosage delivered did not confer prognostic significance. CONCLUSIONS: This study confirmed the association of adverse prognostic implication of positive margins on disease-free survival. Immune compromise was not a significant factor in this small group. Further studies are warranted in this population.