Abstract
Invasive squamous cell carcinoma (SCC), once becoming resistant to chemotherapy or radiation therapy, is quite difficult to treat. In this context, recall of anti-cancer immunity is one of last therapeutic possibilities. Hence, we treated a case invasive SCC with intralesional injection of interleukin (IL)-2. A 75 year-old Japanese woman with multiple SCC on her right lower leg was intralesionally injected with IL-2 twice daily for 10 days. To monitor the effect, immunostaining was conducted using a panel of antibodies, and in situ TUNEL staining was performed to examine apoptotic death of tumor cells upon the IL-2 injection. The intralesional administration of IL-2 led to the marked reduction of the tumor size. Furthermore, immunostaining revealed the marked increase in the number of CD1a positive Langerhans cells surrounded by CD4+ and CD8+ T lymphocytes. in situ TUNEL staining demonstrated apoptosis of the tumor cells upon intralesional injection of IL-2. Collectively, we propose that intralesional injection of IL-2 is worthy of consideration for treatment of SCC, when it becomes resistant to conventional therapies.
