Study of Irofulven Plus Capecitabine in Patients With Advanced Thyroid Cancer

Inclusion Criteria: 18 years of age or older. Cancer of the thyroid confirmed by a biopsy sample. Specific types of thyroid cancer included in this study are anaplastic, differentiated (papillary, follicular, or Hürthle cell), and medullary thyroid cancers. For patients with differentiated (papillary, follicular, or Hürthle cell) thyroid cancer, no more than 1 prior chemotherapy treatment is allowed. Measurable disease is required (at least one lesion at least 2 cm in length by conventional computed tomography (CT) techniques or at least 1 cm by spiral CT scan). Any prior chemotherapy or radiation therapy must be stopped at least 4 weeks before the first dose of study treatment. Prior radioiodine (I131) therapy must be stopped at least 3 (or 6) months before first dose of study treatment (depending on responsiveness to this therapy). Recovery from any toxic effects of prior chemotherapy, radiation therapy and surgery. Patients with reproductive potential must use a medically acceptable contraceptive method. Women of childbearing potential must have a negative pregnancy test at screening. Exclusion Criteria: History of retinopathy. Serious ongoing medical or psychiatric disorder (as determined by the clinical investigator). External beam radiation therapy to >30% of the bone marrow at any time prior to study entry. Prior treatment with irofulven or capecitabine, or protracted infusion of 5-fluorouracil (5-FU) (infusion duration greater than or equal to 5 days) or other fluoropyrimidines. Therapeutic doses of coumarin derivatives (warfarin) 14 days prior to receiving the first dose of study treatment or during the study period. Please note: There are additional criteria that must be met in order to be eligible for this study.