Triapine, Cisplatin, and Radiation Therapy in Treating Patients With Cervical Cancer or Vaginal Cancer

Inclusion Criteria: * Female patients must have histologically confirmed (tumor tissue biopsy) primary clinical stage IB2-IVB cervical cancer or clinical stage II-IVB vaginal cancer not amenable to curative surgical resection alone to be eligible; patients with stage IVB cervical cancer may receive systemic chemotherapy for treatment of metastatic disease a) after the 3-month post-therapy PET scan and b) if the 3-month post-therapy PET scan documents progressive disease at the discretion of the treating physician * Patients with other active invasive malignancies are excluded; patients with prior malignancies (except non-melanoma skin cancer or prior in situ carcinoma of the cervix, patients with synchronous or past history of primary endometrial cancer meeting all conditions of a) stage not greater than IB, b) no more than superficial myometrial invasion, c) without vascular or lymphatic invasion, and d) no poorly differentiated subtypes including papillary serous, clear cell or other FIGO grade 3 lesions; patients with other invasive malignancies who had (or have) cancer present within the last five years are excluded; patients are excluded if they have received prior low abdominal or pelvic radiotherapy for any reason that would contribute radiation dose that would exceed tolerance of normal tissues * Life expectancy of greater than 3 months * Absolute neutrophil count \>= 1,500/uL * Platelets \>= 100,000/uL * Hemoglobin \>= 10 g/dL * Total bilirubin =\< 2.0 mg/dL * AST(S…