Participant must be previously untreated, (no more than 72 hours of steroids, one intrathecal chemotherapy treatment, and/or emergency radiation) PARTICIPANTS FROM COLLABORATING SITES PARTICIPATING IN BIOLOGICAL OBJECTIVES ONLY: Participant must be previously untreated, (no more than 72 hours of steroids, one intrathecal chemotherapy treatment, and/or emergency radiation) Patients requiring emergency radiation therapy are eligible for enrollment on this trial Subjects undergoing emergency surgery Emergency surgery More than 10 VOCs within the past 12 months that required a hospital, emergency room or clinic visit Patients who are receiving an emergency colonoscopy No prior therapy, unless an emergency situation requires local tumor treatment (discuss with principal investigator [PI]) ORAL CAVITY SQUAMOUS CELL CARCINOMA COHORT: Prior surgery, radiation therapy, or chemotherapy other than biopsy or emergency procedure required for supportive care Patient is able to stay within 45 minutes driving time of an emergency room for 28 days after dosing with C. novyi-NT Severe increased intracranial pressure, status epilepticus, or other serious complications from the brain tumor, requiring emergency or urgent intervention Prior surgery, radiation therapy, or chemotherapy other than biopsy or emergency procedure required for supportive care of this oral cavity cancer. Emergency leukapheresis Emergency surgery for abdominal indications Subject is undergoing an emergency surgical procedure; Emergency leukapheresis; Emergency treatment for hyperleukocytosis with hydroxyurea for ? 10 days; Patient is able to stay within 45 minutes driving time of an emergency room for 28 days after doing. Subject needs non-emergency cardiac surgery with cardiopulmonary bypass. Subject needs emergency surgery. Previously untreated AML (except: emergency leukopheresis and/or hydroxyurea during the screening phase to control hyperleukocytosis but must be discontinued at least one day prior to start of study therapy) e. Unstable pulmonary disease requiring hospitalization or emergency room visit within the last 3 months. Emergency case Emergency craniotomies Emergency surgery of any type that does not allow for proper time for protocol review by the patient Patient requiring emergency operations Patients requiring emergency surgical intervention that would be inappropriately delayed by FLT-PET imaging