This pilot study will evaluate the effectiveness of using photodynamic therapy for treatment of cutaneous squamous cell in situ (SCCis). Our hypothesis is that PDT will be effective for treating SCCis. This study will also secondarily evaluate the tolerability of using photodynamic therapy for treatment of SCCis.

Investigators plan to enroll 40 subjects with biopsy proven SCCis. Exclusion criteria include lesion in high-risk site (head, neck, hands, feet), previous severe adverse reaction to topical 20% aminolevulinic acid (Kerastick), previous severe adverse reaction to blue light (BLU-U), allergy to Tegaderm, primary or secondary immunosuppression, history of > 6 skin cancers in the past year, photosensitizing condition such as lupus, or sensitivity to porphyrins.

Age, gender, size, and location of the SCCis will be recorded. All subjects will receive surgical treatment of their SCCis. The control group will undergo a surgical excision of the tumor. After the excision, subjects will be asked to fill out a satisfaction survey. The intervention group will receive PDT plus surgical treatment. Photographs of the lesion will be taken at each study visit. Subjects in the intervention group will then undergo the study procedure of application of topical 20% 5-ALA (Levulan Kerastick; DUSA Pharmaceuticals) to the SCCis. At 3-5 weeks after the initial treatment, the subject will repeat the 3-hour ALA incubation and blue light exposure. At 6 months after the last treatment, subjects in the intervention group will return for clinical follow-up and surgical excision of the lesion. After excision, the specimen will be sent for processing by pathology and subjects will be asked to fill out a satisfaction visual analog scale. All slides will be read by a board-certified dermatopathologist. Side effects will also be monitored using the same graded scale described previously. Mild adverse events that have been associated with PDT, including erythema, skin crusting, superficial blistering, hypopigmentation, and hyperpigmentation. These reactions usually occur during or immediately after the PDT treatment.

Objective: This trial will evaluate the effectiveness of photodynamic therapy (aminolevulinic acid plus blue light) for treatment of cutaneous squamous cell carcinoma in situ (SCCis).

This pilot study will prospectively recruit 40 subjects with biopsy proven SCCis at the time of their visit at University Dermatology East Providence office. Exclusion criteria include lesion in high-risk site (head, neck, hands, feet), previous severe adverse reaction to topical 20% aminolevulinic acid (Kerastick), previous severe adverse reaction to blue light (BLU-U), allergy to Tegaderm, primary or secondary immunosuppression, history of > 6 skin cancers in the past year, photosensitizing condition such as lupus, or sensitivity to porphyrins.

Half of the subjects will be randomized to the control group (n=20), and the remaining subjects (n=20) will be randomized to the intervention group. The subject's age and gender, and size and location of the SCCis will be recorded. For the control group, subjects will undergo a surgical excision of the tumor, which is the gold standard of treatment for SCCis. After the excision, subjects will be asked to fill out a satisfaction survey. They will not receive any PDT treatment.

For the intervention group, photographs of the lesion will be taken at each study visit. A clear transparency film will be used to trace the clinical margins of the lesion, as well as any other distinctive skin markings such as nevi or birthmarks. Subjects will then undergo the study procedure. The area to be treated will be swabbed with an alcohol wipe and allowed to dry. The investigator will apply topical 20% 5-ALA to the SCCis. Then, the area will be covered with Tegaderm film for 3 hours. At the end of 3 hours, the Tegaderm will be removed and the subject will be exposed to a blue light source, which is the standard protocol for treatment with blue light PDT. During administration of the light and immediately afterwards, the subject will be monitored for any side effects, such as erythema, edema, stinging/burning, blisters/crusting, hyperpigmentation, and hypopigmentation. These items will be graded on a scale of 1 to 4 (1=mild and 4=severe) assessed immediately after treatment. This process will be repeated at the next visit 3-5 weeks later. At six months after the last treatment, subjects in the intervention group will return for clinical follow-up and surgical excision of the lesion. Patients will complete a satisfaction survey at the end of this visit.

Inclusion Criteria:

1. Age > 18, any gender
2. Biopsy proven SCCis without evidence of microinvasion beyond the epidermis
3. Low-risk site (trunk, arms, legs)
4. Clinical presence of tumor at biopsy site to ensure that biopsy itself was not curative
5. Lesion <2cm
6. Subject amenable to surgical excision at 6 months after the last PDT treatment

Exclusion Criteria:

1. High-risk site (head, neck, hands, feet)
2. Previous severe adverse reaction to topical 20% aminolevulinic acid (Kerastick)
3. Previous severe adverse reaction to blue light (BLU-U)
4. Allergy to Tegaderm
5. Exclusion of any patient with primary or secondary immunosuppression
6. History of > 6 skin cancers in the past year
7. Photosensitizing condition such as lupus
8. Sensitivity to porphyrins