Purpose: To determine the disease control rate and toxicity of treating patients with aggressive cutaneous squamous cell carcinoma (CSCC) with neoadjuvant gefitinib.
Experimental design: A prospective phase II clinical trial evaluating neoadjuvant gefitinib given prior to standard treatment with surgery and/or radiotherapy. Patients with stable disease after one cycle received escalated doses. Patients who responded were given gefitinib during radiation therapy, as well as maintenance therapy after definitive treatment. We analyzed the correlation between epidermal growth factor receptor (EGFR) expression, mutation status, and gene copy number on available tissue samples and clinical response.
Results: Twenty-three patients were accrued and 22 patients were evaluable for response prior to definitive local treatment; complete responses were attained by 18.2% of patients and partial responses by 27.3%. Grades 2 to 3 toxicities were observed in 59.1% of patients experiencing class-specific effects during induction therapy. After induction, 11.8% underwent surgery alone, 17.6% had definitive radiation, 11.8% were treated with radiation and concurrent gefitinib, and 47% had surgery with postoperative radiation and concurrent gefitinib. Median follow-up for the censored observations was 32 months. Two-year overall, disease-specific, and progression-free survival rates were 72.1%, 72.1%, and 63.6%, respectively. No EGFR-activating mutations were identified in tumor samples available from 10 patients. No associations between EGFR correlative studies and patient outcomes were identified.
Conclusions: Gefitinib, in the neoadjuvant setting, was active and well tolerated in patients with aggressive CSCC and did not interfere with definitive treatment. In view of the 18% complete response rate we observed, EGFR tyrosine kinase inhibitors should be further explored in the treatment of aggressive CSCC.