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 3 different dose levels of nitro glycerin patches (0.2; 0.4; and 0.6 mg/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.
The purpose of this study is to determine whether topical nitroglycerin in addition to 5-flourouracil and radiation therapy are effective in the treatment of operable rectal cancer.