Epidermal Growth Factor Receptor-targeted Therapy in Squamous Cell Carcinoma of the Penis: A Report of 3 Cases

Abstract

To describe 3 cases of advanced refractory penile cancer treated with targeted therapy against the epidermal growth factor receptor (EGFR). We identified 3 patients with advanced penile cancer who had disease progression after platinum chemotherapy refractory and who subsequently received EGFR-targeted therapy. Their tumor tissue was evaluated for expression of EGFR by immunohistochemistry and messenger ribonucleic acid quantitation and was also tested for the presence of human papillomavirus deoxyribonucleic acid by line hybridization. K-ras mutation was evaluated by polymerase chain reaction for 6 mutations in codon 12 and 1 mutation in codon13. One patient responded to cetuximab and remains disease-free 42 months after presentation. One patient responded to panitumumab, then suffered relapse. One other progressed through EGFR-targeted therapy. EGFR expression by immunohistochemistry was 1-2+ in all cases, and messenger ribonucleic acid expression ranged from 4.08 to 7.33. No K-ras mutations or human papillomavirus deoxyribonucleic acid was detected. We report 3 cases in which EGFR-targeted therapy was used to treat platinum-refractory penile cancer patients. Because 2 of the 3 had clinical benefit, future prospective trials of EGFR-targeted therapy in penile cancer are warranted.