A Phase la Trial of Photodynamic Therapy With HPPH (2-1 (Hexyloxyethyl)-2-devinylpyropheophorbide-a) for Treatment of Dysplasia, Carcinoma in Situ and T1 Carcinoma of the Oral Cavity and/or Oropharynx.

Inclusion Criteria:

- Patients with moderate to severe dysplasia and/or squamous carcinoma-in-situ of the
oral cavity and/or oropharynx.

- Patients with T1 squamous cell carcinoma of the oral cavity and/or oropharynx.

- Patient may have primary and/or recurrent lesions to be treated.

- Diagnosis must confirmed by biopsy.

- Prior therapy of any type is allowed.

- Male or female patients at least 18 years old. Female patients must not be pregnant
and must be practicing a medically acceptable form of birth control, be sterile or
post-menopausal. Male patients should be using a medically acceptable form of birth
control or be sterile.

- Patients must have an ECOG score of 0-2 (Appendix A 1 ).

- Patient or legal representative must understand the investigational nature of this
study and sign an Independent Ethics Committee/Institutional Review Board approved
written informed consent form prior to receiving any study related procedure.

Exclusion Criteria:

- Patients with T2 or greater squamous cell carcinoma.

- True tongue base lesions (as determined by the treating physician).

- Patients with severe trismus that prevents adequate access to the lesion for
treatment light delivery (as determined by the treating physician).

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

- Patients with impaired hepatic (alkaline phosphatase (hepatic) or SGOT;:3 times the
upper normal limits).

- Patients with minimal impairment of renal function (total serum bilirubin;: 2 mg/dl,
serum creatinine;: 2 mg/dl)

- Unwilling or unable to follow protocol requirements.

- Any condition which in the Investigator's opinion deems the patient an unsuitable
candidate to receive study drug and or light treatment.

- Patients on concurrent chemotherapy or radiation therapy or less than 4 weeks after
the last dose of chemotherapy or radiation therapy.

Inclusion of Women and Minorities:

- Both men and women and members of all races and ethnic groups are eligible for this
study.