Dose Escalation Trial of Nitroglycerin, 5-flourouracil and Rad Therapy for Rectal Cancer

This is an open label, non-randomized, multi-cohort, dose escalation trial to evaluate the
safety, tolerability, feasibility and maximum tolerated dose (MTD) of topical nitroglycerin
in addition to 5-flourouracil and radiation therapy for neo-adjuvant treatment of, T3-T4 or
clinically node positive, operable rectal cancer.

Patients that would otherwise be eligible for concurrent neo-adjuvant chemotherapy with
continuous infusion 5-FU, for locally advanced operable rectal cancer, will be assigned to 4
sequential cohorts of 4 different dose levels of nitro glycerin patches (0.2; 0.4; 0.6 and
0.8mg/hr). Each cohort will consist of 3 patients. All patients will receive radiation
therapy, 45-50 Gy in 25-28 fractions to the pelvis along with continuous infusion 5-FU
225mg/M2 for the duration of the radiation therapy. The radiation therapy will be planned
and delivered as per institutional standard of care for the Dallas VAMC radiation oncology
department.

Inclusion Criteria:

- Biopsy proven Rectal Adenocarcinoma

- Histological diagnosis of operable T3-4, or T1-4 node positive, M0 rectal
adenocarcinoma using endorectal ultrasound and/or MRI in addition to Computed
Tomography (CT) of the chest, abdomen and pelvis for pre-study staging Acceptable
alternatives for systemic staging instead of CT chest , abdomen, pelvis are CT
abdomen and pelvis plus a Chest X-ray or a PET/CT

- Ability to give informed consent and willingness to adhere to study protocol

- Age ≥ 18 years and otherwise eligible to receive medical care at the Dallas VA
Medical Center.

- Eastern Cooperative Oncology Group (ECOG) Performance Status of 0-2

- Adequate hematological, hepatic and renal function defined as in protocol.

Exclusion Criteria:

- Any condition that would hamper informed consent or ability to comply with the study
protocol

- Significant history of cardiac disease, e.g. uncontrolled hypertension, unstable
angina, decompensated congestive-heart failure, myocardial infarction within the last
six months or ventricular arrhythmias requiring medication.

- Pregnant and lactating women.

- Patients taking Phosphodiesterase - 5 inhibitors (e.g. Sildenafil, Vardenafil or
Tadalafil) and is unable to stop for the duration of the chemoradiotherapy.