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 can be primary or recurrent, Stage 0 or I, N0M (any).

- Patients must have no contraindications 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.

- Operable patients are not excluded.

Exclusion Criteria:

- Patients with tumors of grade greater than T-1.

- Porphyria or hypersensitivity to porphyrin or porphyrin-like compounds.

- WBC <2,000; platelet count <50,000, prothrombin time 1.5 times above the 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.

- If the patient has cancer other than non-melanoma skin cancer they must be deemed
disease free by their treating physician.