- 1. T4 cutaneous SCC as determined by physical exam, imaging studies, prior resections or biopsy. T4 disease is defined as tumor that invades deep extradermal structures such as cartilage, skeletal muscle (e.g., muscles of facial expression), parotid gland or bone.Patients with a T2 or greater squamous cell carcinoma of the lower lip who will require post operative radiation will be allowed.