Patients will receive Levulan Kerastick (aminolevulinic acid) to the face and/or scalp (if both are needed, treated separately on back to back days); incubation: 2.5 hours and blue light photodynamic therapy utilizing the DUSA BLU-U device; illumination: 1000 seconds (16 min, 40 secs); administered quarterly for 3 years. Patients who change systemic immunosuppression regimens or add or increase systemic chemoprevention while in the study will be excluded from the overall analysis. The patients will be evaluated by the principal investigator every 3 months, prior to photodynamic therapy (PDT) administration.