One of three main types of cells in the top layer of the skin (the epidermis), squamous cells are flat cells located near the surface of the skin that shed continuously as new ones form. Squamous Cell Carcinoma (SCC) can appear as scaly red patches, open sores, rough, thickened or wart-like skin, or raised growths with a central depression. At times, SCCs may crust over, itch or bleed. The lesions most commonly arise in sun-exposed areas of the body. This Clinical Trial provides a vaccine on (up to) three occasions that is injected directly into the lesion on the skin, which triggers the immune system to attack the cancer cells.