Patient's with High Grade Dysplasia, Carcinoma in situ or Early Adenocarcinoma in Barrett's Esophagus are injected with HPPH and one day later are endoscopically treated with light from a laser.

Inclusion Criteria:

• Patient must have biopsy proven high-grade (severe)dysplasia, carcinoma-in-situ or early stage adenocarcinoma
• Patient may have received prior therapy; e.g.Nd-YAG laser, radiation therapy or chemotherapy. At least one-month must have elapsed between prior treatments and PDT
• Tumors (HGD/CIS or early adenocarcinoma) can be primary or recurrent, Stage 0 or I N0M (any)
• Patients must have no contraindication to endoscopy
• Male or female patients must be 18 years old or older. Female patients must not be pregnant and must be practicing a medically acceptable form of birth control or be sterile or post-menopausal. A Pregnancy test is required and must be negative.
• Patients must sign an Informed Consent according to FDA guidelines and be acceptable to the RPCI IRB
• Patients must have a Karnofsky status 50 or above.
• Patients with early invasive adenocarcinoma will be included only if they are considered poor surgical risks, have failed or refused XRT/chemo, or refused surgery.
• If the patients has had cancer other than non-melanoma skin cancer, their treating physician must deem them disease-free.

Exclusion Criteria:

• Patients with tumors of grade greater than T-1.
• Porphyria or hypersensitivity to porphyrin or porphyrin-like compounds
• WBC<4000; platelet count<100,000; prothrombin times 1.5 times above upper normal limit.
• Patients with impaired renal and/or hepatic function (total serum bilirubin > 3.0 mg/d, serum creatinine>3 mg%, alkaline phosphatase (hepatic) or SGOT> 3 times the upper normal limit.
• Patients on concurrent chemotherapy or radiation therapy will be excluded as well as those having received prior treatment for the esophageal cancer within 4 weeks of enrollment.